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The links below take you to the abstracts. 

There you will find another link to most of the PowerPoint presentations. These are in Adobe Acrobat format. 

You can download the acrobat program to read the pdf files from

Navigational assistance  in positioning the femoral and tibial tunnels in anterior cruciate ligament replacement  

 Jürgen Eichhorn, MD

  MRI Analysis of Anatomic Variables  in the Etiology of  Anterior Cruciate Ligament Injury in Female Athletes  

K Willits,  A Kirkley, L Thain, A Spouge, PJ Fowler

Thirty Year Follow-up of Isolated Anterior Cruciate Ligament Injuries

 Dean C. Taylor, MD

RISK FACTORS ASSOCIATED WITH NON-CONTACT ACL INJURY: A PROSPECTIVE FOUR-YEAR EVALUATION OF 859 WEST POINT CADETS.

UHORCHAK MD

Skiing with "carving" skis: Different styles - different load patterns -different injury patterns?
- A biomechanical analysis utilizing force plates fixed to the skis

 Niklaus F. Friederich, MD

A Six-Month Biomechanical and Histological Evaluation of Porcine Xenografts for Anterior Cruciate Ligament Reconstruction

Stone KR

The Effect of Mechanical Stress and Cytokines on Nitric Oxide Production in the Menisci

C. Fink

 Magnetic Resonance Imaging of the Multiple Ligament Injured Knee.     

Hollis G. Potter, MD

Anatomic, Physeal Sparing Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients Using Quadruple Hamstring Grafts

Allen F. Anderson

Tension in the Normal Anterior Cruciate Ligament  

Markus P. ARNOLD

ARTHROSCOPIC MANAGEMENT OF KNEE OSTEOARTHRITIS

G.  BELLIER 

  ANTERIOR CRUCIATE RECONSTRUCTION COMBINED WITH VALGUS TIBIAL OSTEOTOMY

T. Ait Si Selmi

Tissue-engineering Technique for Repair of Cartilage Defect with ACL Deficiency

Mitsuo Ochi

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING A FREE-HAND COMPUTER ASSISTED DRILL GUIDE

Menetrey J

SINGLE INCISION ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING PATELLAR TENDON AUTOGRAFT: WHAT ARE THE RESULTS AFTER A TEN YEAR FOLLOW-UP?

Alwin Jäger

Pulsed Electromagnetic field energy will improve the mechanical properties of tendon graft to bone tunnel healing.  

 Belanger, MD

Tibio Femoral Kinematics of the Weight Bearing Living Knee With and Without An Intact Anterior Cruciate Ligament 

Andy Williams; Ed Dunstan; James Robinson; David Hunt;

Andy Williams

Intraoperative Measurement of Knee Joint Kinematics in ACL Repair

AA Amis

 The Use of Braces that Cushion Extension in Patients with ACL Insufficiency,

Edwin C. Bartlett M.D

Clinical Examination of the Knee – A Dying Art

Brian Hurson

Revascularization following ACL reconstruction: evaluation with MRI in the oblique axial view

Roland M. Biedert

Two-year Results on Double-Looped Semitendinosus and Gracilis Grafts Fixed with a Bioabsorbable Soft Tissue Interference Screw.

D. H. Johnson

Early Weight Bearing after Acute Cartilage Injury Increases Joint Inflammation.  

James R. Bocell 

POSTEROLATERAL COMPLEX INJURIES OF THE KNEE ASSOCIATED WITH PERONEAL NERVE DYSFUNCTION\

Boyd, JL, MD

A Controlled Study of Autologous Chondrocyte Implantation versus Marrow Stimulation Techniques for Full-Thickness Articular Cartilage Lesions of the Femur

Browne, JE 

5-Year Multicenter Outcome of Autologous Chondrocyte Implantation of the Knee: Results in the First 100 Consecutive Patients

Browne, JE 2

Outcome criterias after acl-replacement – does the patient benefit from acl-replacement?

Burkart P

Treatment Trends with Anterior Cruciate Ligament, Posterior Cruciate Ligament, Medial Collateral Ligament, and Cartilage Problems

John D. Campbell, M.D.

Radiofrequency Electrothermal Shrinkage of the Anterior Cruciate Ligament

Thomas R. Carter, M.D.

Influence of Chronicity, Gender, and Age on the Correlation Between Chondral and Meniscal Injury, in ACL Deficient Knees

Christopher Kaeding

RESULTS OF REPEAT MENISCUS REPAIR  

ILYA VOLOSHIN, MD

Postoperative intraarticular patient-controlled analgesia after arthroscopically assisted anterior cruciate ligament reconstruction.

Denti M, Giovannini M

Osteochondral Transplantation with Donor Site Reconstruction and MRI Analysis.

D.P.  Johnson  MD

KNEE AS ORTHOPAEDIC ROSETTA STONE

Scott F. Dye, M.D

A PROSPECTIVE RANDOMIZED STUDY OF THE USE OF A BRACE IN SLIGHT HYPEREXTENSION VS. A STRAIGHT BRACE IN THE IMMEDIATE POSTOPERATIVE PERIOD AFTER ACL RECONSTRUCTION. 

Ejnar Eriksson

Bioabsorbable versus metallic tibial fixation in ACL reconstruction: a clinical and radiographic study

Julian Feller

STRUCTURE-FUNCTION RELATIONSHIPS IN HEALING LIGAMENT SCARS

C.B. Frank

Resultant force in the lateral meniscus and bony contact in the intact and ACL-deficient knee by applying valgus torque.

Fukuda, Y

Evaluation of the sensitivity of 3D-SPGR MRI sequence to detect articular cartilage lesions of the knee, with a focus on ACL injured knees

James N. Gladstone, MD

CROSS PINNED INTERFERENCE SCREW

MARLOWE GOBLE, M.D

BIOABSORBABLE INTERFERENCE SCREW FIXATION OF HAMSTRING ACL GRAFTS:  THE EFFECT OF SCREW DIAMETER ON PULL-OUT STRENGTH

Charles A. Gottlob, MD

SECONDARY TENSIONING OF AN ELONGATED ACL GRAFT

P. Hertel

Correlation of the injury pattern and a videoanalysis of anterior cruciate ligament tears in world cup alpine ski racers

Christian Hoser, MD

Use of Allograft Osteochondral Transfer (OATS) and Allograft Lateral Meniscus to restore the Lateral Compartment in an ACL Deficient Knee.

Stephen Houseworth, M.D.

Guidelines for Tibial and Femoral Tunnel Placement in the Coronal Plane that Minimize Anterior Cruciate Ligament Graft Tension in Flexion and Impingement Against the Posterior Cruciate Ligament: A Study in Cadaveric Knees

Stephen M. Howell, MD

The Effects of Radiofrequency Treatment on Chondrocytes and Articular Cartilage Matrix of Fibrillated Cartilage

Chris Kaeding MD

ACL STRAIN DURING SIMULATED FREE-SPEED WALKING

Jason L. Koh

 Differences in Core Stability between Male and Female Collegiate Athletes as Measured by  Trunk and Hip Performance

M.L. Ireland,

 Treatment of severe Arthrofibrosis

Philipp Lobenhofer

Response of tibial tunnel and tibial inlay posterior cruciate ligament graft reconstructions to cyclic loading.

D. McAllister,

The Role Of Rehabilitation Brace In Restoring Knee Extension After Anterior Cruciate Ligament Reconstruction

Gianluca Melegati

  "COMPARISON OF ONE‑LEG HOP FOR DISTANCE SCORES IN THE ANTERIOR CRUCIATE LIGAMENT DEFICIENT POPULATION WITH A GROUP OF HEALTHY CONTROLS"

P Marks

 Donor site morbidity after anterior cruciate ligament reconstruction with ipsilateral versus contralateral harvesting of bone-patellar-tendon graft.

H.H. Paessler,

ACL RECONSTRUCTION IN THE SKELETALLY IMMATURE ATHLETE:  COMPARISON OF TWO TECHNIQUES

George Paletta, MD,

Association of HLA with primary arthrofibrosis after ACL reconstruction  

Hermann Mayr, M.D

Outcome criterias after acl-replacement – does the patient benefit from acl-replacement?

Thomas W. Patt, MD 

 Double-Bundle PCL Reconstruction  

Russell F. Warren,

Revascularization following acl reconstruction: evaluation with mri in the oblique axial view  

Roland M. Biedert *, Klaus Herbert #, Christian Kurz 

COLLAGEN MENISCUS IMPLANTS (CMI): MULTICENTER CLINICAL TRIALS UPDATE

William G. Rodkey, DVM

DOES “OVERTIGHTENING” AN ANATOMICALLY PLACED ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION GRAFT  

Marc R. Safran, MD

BUCKETHANDLE MEDIAL MENISCUS TEARS IN ACL RECONSTRUCTED KNEE: LONG TERM OUTCOME

K. DONALD SHELBOURNE, MD

Lysis of Pretibial Patellar Tendon Adhesions (“Anterior Interval Release”) to Treat Anterior Knee Pain After ACL Reconstruction  

J. Richard Steadman MD

Treatment of Grade II Medial Meniscal Tears  with Persistent Joint Line Pain

TP Branch

Microperforation for Chronic ACL/MCL Laxity: Results in a Rabbit Animal Model and Human Experience   

Thomas D. Rosenberg, M.D.

The Multipotential Capacity of Stromal Cells Derived from the Infrapatellar Fat Pad of the Knee  

Thomas Parker Vail, MD

Tensile Properties of an ACL Graft after Press-Fit Fixation  

Freddie H. Fu, M.D.

Metabolic changes in knee joint synovia during reperfusion after arthroscopy - an in vivo study using the microdialysis technique

Wredmark T

Links to additional PowerPoint Presentations given during the ACL study group meeting in Big Sky 

ACL Shrink - Steve Houseworth

Balance Board Training - Engstrom 

Research Methodology - Beynnon

ACL Outcomes - IKDC - Anderson 

Hormone Levels at the time of ACL injury - Braun

Stratification of Cartilage Injury After Acute ACL Injury - Potter

Effects of Radiofrequency on Articular Cartilage - Vangsness

ACL outcome comparisons between males and females - Ireland

Critical Issues in ACL - Shelbourne

Case Presentation - Mueller 

ACL in the Mountains - Losee

Abstracts and Links to the PowerPoint Presentations

Jürgen Eichhorn, MD

  Navigational assistance  in positioning the femoral and tibial tunnels in anterior cruciate ligament replacement

The Fowler · Kennedy Sport Medicine Clinic

            The University of Western Ontario

            London  Canada  

Click here for the PowerPoint presentation

   Dean C. Taylor, MD, LTC, MC, USA    

Click here for the PowerPoint presentation

Thirty Year Follow-up of Isolated Anterior Cruciate Ligament Injuries

COAUTHORS:            Matthew Posner, BS, CPT, FA, USA

Walton W. Curl, MD, COL, USAR

John A. Feagin, MD, COL (ret), USA

TITLE: Update on Anterior Cruciate Injury Rate Differences Between Female and

 Male Cadets at the United States Military Academy

PRESENTER:             Dean C. Taylor, MD, LTC, MC, USA

CO-AUTHORS:         Matthew Posner, BS, CPT, FA, USA

John A. Kragh, MD, MAJ, MC, USA

                                    John M. Uhorchak, MD, COL, MC, USA

Hollis G. Potter            , MD               

Magnetic Resonance Imaging of the Multiple Ligament Injured Knee.               

            Hollis G. Potter, MD, Marc Weinstein, MD, Answorth A. Allen, MD, Thomas L. Wickiewicz, MD, and  

Allen F. Anderson, M.D.

Click here for the PowerPoint presentation

Anatomic, Physeal Sparing Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients Using Quadruple Hamstring Grafts

            Markus P. ARNOLD

           Tension in the Normal Anterior Cruciate Ligament A Cadaver Study with Clinical Relevance

Introduction : Efficiency of arthroscopic procedures in osteoarthritis of the knee has not been clearly demonstrated.

    ANTERIOR CRUCIATE RECONSTRUCTION COMBINED WITH VALGUS TIBIAL OSTEOTOMY - Long term result –

Menetrey J,

ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING A FREE-HAND COMPUTER ASSISTED DRILL GUIDE

Alwin Jäger,

Click here for PowerPoint presentation

·         The Hypothesis - What is the question?

·         Method – How was the question investigated?

·         Results – What were the results?

·         -Statistical analysis

·        Conclusions

M Belanger, MD

Click here for the PowerPoint presentation

Andy Williams  

Click here for the PowerPoint presentation

Andrew A. Amis (a.amis@ic.ac.uk)

Click here for the PowerPoint presentation

Intraoperative Measurement of Knee Joint Kinematics in ACL Repair

AMJ Bull, PH Earnshaw, A Smith, MV Katchburian, A Hassan, AA Amis

Imperial College, and Guy’s and St. Thomas’ Hospital NHS Trust, London

Brian Hurson

Roland M. Biedert  

Click here for PowerPoint presentation

Revascularization following ACL reconstruction: evaluation with MRI in the oblique axial view

*, Klaus Herbert #, Christian Kurz #

* Institute of Sport Sciences, Orthopaedics and Sports Traumatology, CH-2532 Magglingen, Switzerland

# Department of Radiology, Clinic Linde, CH-2500 Biel, Switzerland

D. H. Johnson  

Click here for the PowerPoint presentation

James R. Bocell    

Click here for the PowerPoint presentation

·         The Hypothesis – What is the question?

·         Method – How was the question investigated?

·         Results – What were the results?

-Statistical analysis

·         Conclusions

Boyd, JL, MD  

Browne, JE

Browne JE,

Click here for the PowerPoint presentation

Burkart P  

 John D. Campbell, M.D.  

Thomas R. Carter, M.D.  

Radiofrequency Electrothermal Shrinkage of the Anterior Cruciate Ligament

Click here for the PowerPoint presentation

  Click here for PowerPoint presentation

Title and Authors:   “Influence of Chronicity, Gender, and Age on the Correlation Between Chondral and Meniscal Injury, in ACL Deficient Knees”, Christopher Kaeding M.D., Lawrence Kusior M.D., Aasha Sinha PhD, Joe Hanna M.D.

Hypothesis/Study Question:  What is the relationship between chondral and meniscal injury in Anterior Cruciate Ligament Deficient Knees and what influence are chronicity, gender, and age at time of injury?

Methods:  The intra-articular findings of the knee were prospectively documented at the time of surgery in all ACL reconstructions performed at our institution by the senior author from 1991 – 2000.  All surgery and documentation were performed by the same surgeon.  Findings documented included:  size and location of meniscal tears; size, location and severity of chondral injury; ligament exam; and gender.  Activity at time of injury, age at time of injury, time interval between injury and reconstruction, and history of prior surgery were obtained from the office chart.  Meniscal tears were graded by percent of meniscal tissue resected in increments of 10 (10% - 100%).  In the case of meniscal repairs, the same grade of size was done on the amount of tissue that would have been resected had the tear not been repaired.  Meniscal tear location was recorded as medial or lateral.  Chondral injury was graded in severity on a 1 –4 scale.  1 – softening, 2 – superficial damage. 3 – deep partial thickness damage. 4 – exposed bone.  Chondral injury location was recorded as medial femoral condyle, lateral femoral condyle, medial tibial plateau, lateral tibial plateau, patella, or trochlear groove.  Chondral injury size was recorded as number of square millimeters.  Chronicity was recorded as number of months between time of injury and reconstruction.  This data was input into an Access database.  For this study exclusion criteria included:  prior ligament reconstruction or arthrotomy, associated ligament laxity other than an incomplete medial collateral ligament tear.  This resulted in a study group of 980 patients. The data from these patients was analyzed with the assistance of a faculty statistician.  For the purposes of this study the following definitions were used: chondral injury was defined as any grade 3 or 4 lesion or any grade 2 lesion greater than 300 square mm in size.  Chronicity was defined as the time interval between  injury and reconstruction with “acute” being less than 3 months  and “chronic” being greater than 12 months between time of injury and reconstruction.  “Younger” patients were 20 years of age or less at time of  injury.  “Older” patients were over 30 years of age at time of injury.

Results

Meniscal Tears:  If we use continuous values for age and chronicity, a logistic regression of incidence of meniscal tear on gender, age at time of injury, and chronicity yielded gender and chronicity as statistically significant predictors of meniscal tear.  Given a subjects chronicity, his (or her) age at time of injury has no affect on incidence of meniscal tear but gender does.  This logistic regression model results in an increase in odds of a meniscal tear by a factor of 1.58 if the subject is male or if chronicity is 40 months.

Chondral Injury:  Incidence of chondral injury correlated with presence of a meniscus tear. (chi square test p-value < .0001).  A logistic regression model revealed that the size of meniscal tear correlated strongly with chondral injury.  With respect to chronicity, even within each meniscal group (tear/no tear), the incidence of chondral injury increased substantially with greater chronicity.  Gender did not contribute to risk of chondral injury once meniscus tear and chronicity were established.  Age at time of injury did contribute to risk of chondral injury even after meniscus tear and chronicity are established.

Gender:  Male gender is a risk factor for meniscal tear.  Once meniscus tear is established, gender plays no further role in assessing the risk for chondral injury.

Chronicity:  Time to reconstruction played a key role in the risk for both meniscal tear and chondral injury.  A delay of one year increases the odds of meniscal tear by 15% and the odds of chondral injury by 21%.  These effects hold within each meniscal tear, gender and age category.

Age:  Age at time of injury is a risk factor for chondral injury. The odds of chondral injury doubles with each increase of 9 years.  This effect holds within each meniscus tear, and chronicity category.  Age appears to be related to meniscus tear only through chronicity.  Once chronicity is fixed, age at time of injury plays no further role in assessing the risk for meniscal tear.

This is a study of ACL deficient knees that came to surgical reconstruction.  It is not a natural history study of ACL injuries.  Though the acute reconstruction data would reflect well the injury pattern of acute ACL tears as the vast majority of acute ACL injuries presenting to our institution during this time underwent ACL reconstruction.

AUTHORS: ILYA VOLOSHIN, MD; KENNETH E. DEHAVEN, MD; MARK J. ADAMS, MD

TITLE: RESULTS OF REPEAT MENISCUS REPAIR

Click here for the PowerPoint presentation

1) Hypothesis:

Repair of “repairable” menisci has become the standard of care for initial meniscal tears.  However, the efficacy of repeat repair of retorn menisci has not been demonstrated.  The goal of the study is to evaluate and document the clinical outcomes and radiographic findings of repeat repair of retorn menisci, and test the hypothesis that repeat repair of suitable lesions provides comparable outcomes to initial repair.

2) Method:

Eighteen consecutive patients with repeat meniscal repairs performed at our institution between May 1987 and February 1999 were the study group.  Indications and technique were the same as for primary meniscus repair.  Seventeen repeat repairs were performed by the senior author and one by another surgeon.  All eighteen patients were available for follow-up for evaluation by history, physical examination, KT-1000 arthrometer testing, Lysholm II score, Tegner activity score, International Knee Documentation Committee (IKDC) score, and weight-bearing radiographs (for patients with follow-up greater than 5 years).  The mean follow-up was 6.6 years (range 2.4 – 13.8 years).

3) Results:

Data:

a)       Initial repair: The average age of the patients during initial meniscal repair was 22 years (range 12 – 40 years).  Eleven meniscal repairs were lateral and seven were medial.  Six patients had ACL reconstruction performed at the same time as the initial meniscal repair.  All of the patients had symptom free period of time after the initial repair with subsequent reinjury with the exception of one patient who was suspected to have retorn his meniscus 88 days after initial repair.  The average duration of the initial repair was 3.9 years (range 0.2 – 14.7 years).

b)       Repeat repair: The average age of the patients during repeat meniscal repair was 26 years (range 12 – 46 years). The mean follow-up after repeat meniscal repair was 6.6 years (range 2.4 – 13.8 years).  Five patients traumatically tore the re-repaired menisci at the site of the repeat repair.  Of these, four have undergone partial meniscectomies and one has undergone a third repair of the meniscus.  Ten of the remaining 13 patients with clinically intact menisci demonstrated successful relief of symptoms and return to strenuous level of activity.  The other three patients of the thirteen deteriorated clinically and have symptoms with activities of daily living.  The mean Tegner activity score for the thirteen patients with clinically intact menisci was 6.3 (range 1 – 10).  Radiographic data for patients with 5 or more years follow-up is incomplete at this time but will be available for presentation.

Descriptional statistical analysis:

        The survival rate of repeat repair of torn “repairable” menisci is 72%

        77% of patients with clinically intact menisci had relief of symptoms and returned to strenuous level

        of activity.  Mean Tegner activity score is 6.3 (range 1—10). 

4) Conclusion:

The survival rate of repeat repair appears to be somewhat lower than primary repair. However, repeat repair of suitable cases, for most patients, provides relief of symptoms and allows return to strenuous levels of function while appearing to preserve biomechanical role of the meniscus.

  Denti M, Giovannini M.

Click here for the PowerPoint presentation

Postoperative intraarticular patient-controlled analgesia after arthroscopically assisted anterior cruciate ligament reconstruction.

*, Bigoni M**, Lo Vetere D., Moioli M.

Sports Traumatology and Arthroscopic Surgery Unit, Galeazzi Orthop.,Inst., Milan

* Anesthesia and Intensive Care Dept. S. Gerardo Hospital, Monza

** Orthopedic and Traumatology Dept. S. Gerardo Hospital, Univ. Milano Bicocca,  Monza, Italy.

Postoperative pain after arthroscopically assisted anterior cruciate ligament reconstruction is usually severe: average expected Visual Analog Scale

(VAS ) pain score is 7/10. Intrarticular analgesia is widely used because its efficacy has been extensively documented. Aim of the present study is to assess the efficacy of new postoperative analgesia technique based on patient controlled (PC) administration of local anaesthetic intraarticularly or at the site of patellar tendon harvesting.

Study design: Prospective, double blind, randomised study in a community and teaching hospital. Main efficacy variables were postoperative pain score and postoperative analgesic requirement.

METHODS: 37 consecutive patients undergoing arthroscopically assisted BPTB ACL reconstruction were randomised, on the basis of a computer generated list of numbers, to one of the following postoperative analgesic regimens: 1) intraarticular (IA) PC analgesia; 2) patellar tendon (PT) harvesting site PC analgesia; 3) placebo (pla): normal saline solution PC administered into an external hidden reservoir. All patients were granted a conventional postoperative analgesia with ketoprofen 100mg i.v. each dose, administered on patient’s demand. If both study analgesia and conventional analgesia proved to be ineffective, morphine 10mg sc was administered as rescue analgesic.

Ropivacaine 0.5% was used as analgesic solution in IA and PT groups. PC administration of study solution was performed through an entirely mechanical device (Paincare2000), which conveyed, every the patients pushed a release button, 4ml boluses to peripheral sites, via a soft catheter, positioned by one of the investigators at the end of the surgical procedure.

Being aware of the randomisation group, this investigator did not take part in the postoperative measurements or in data analysis before the randomisation code was broken.

The infusion device does not allow a lock-out interval. Postoperative measures (VAS pain scores, Ketoprofen and morphine consumption, occurrence of local anaesthetic side effects) were taken 1, 3, 6, 12, 18, 24 and 36 hours after surgery by an investigator blinded to the randomisation. The study was designed with a 95% potency, a=0.05 in order to detect a difference in rescue analgesic consumption of 200mg. Data were compared using t- and Mann-Whitney U-test.

RESULTS. VAS score values were not significantly different between groups at all times. Patients in IA and PT groups required significantly less ketoprofen compared whit pla patients (IA:137.5+109.1mg, PT:109.1+70mg, pla:463.6+128.6; p<0.001).

Postoperative rescue analgesic (morphine) was required only by patients in pla group.

Pla patients required ketoprofen significantly earlier (236+70min after surgery) than both IA (466+330 min; p<0.05) and PT (467+266 min; p<0.05) groups.

Two IA patients and two PT patients did not require any conventional analgesia.

No drug-related adverse events were observed. One PT patient, not included in the efficacy analysis due to inadvertent disconnection of the catheter, showed transient shivering and mild hyperthemia, which lasted less than 1 day.

DISCUSSION. This study showed that intraarticular analgesia, usually administered, as a single bolus before or after arthroscopic surgery, is also clinically effective when administered as patient controlled administration.

Patient controlled analgesia was equally effective when local anaesthetic was administered at the site of harvesting of the patellar tendon. These data suggest that intraarticular tissues and surgical wound equally contribute to generate postoperative pain.

Optimal analgesia might be achieved by simultaneous patient controlled administration of local anaesthetics at both sites. The infusion device proved to be safe and effective.

Author/Presenter:  D.P.  Johnson  MD, 

The Chesterfield Hospital,  Bristol,  UK.

  Osteochondral Transplantation with Donor Site Reconstruction  and MRI Analysis.  

Click here for the PowerPoint presentation

Introduction         

The management of articular cartilage lesions is difficult due to the mechanical environment and the poor regeneration capacity of articular cartilage. Such defects are increasingly recognised in association with other injuries and sport. Several surgical techniques have been described. Osteochondral Transplantation (OCT) has been proposed for full thickness articular cartilage defects of 10 to 25 square millimetres in area. The technique usually harvests osteochondral pegs from the lateral femoral condyle. However early reports have increasingly noted donor site morbidity from the patello-femoral joint.

Aims                     

We describe the early experience of four cases of OCT with donor site problems and an alteration in the surgical technique used in a subsequent 18 cases in which such donor site morbidity was eliminated.

Methods

Our initial experience was of 4 patients aged 32-51 years with a full thickness aritcular lesion of the articular cartilage of the knee, of an average area of 1.7cm (1 – 2.25 cm). The grafts (2 – 5) were harvested from the lateral edge of the femoral trochlear utilising arthroscopy with mini-arthrotomies. Subsequently a further 18 patients aged 20-47 years with similar full thickness articular cartilage lesions of average area 1.7cm (0.45 –3 cm) underwent OCT utilising the OATS instrumentation (Arthrotec), in which the recipient site is removed rather than drilled out. The grafts (1-3) were harvested in the same way from the same sites. However the recipient site plug was then replaced into the donor site hole. The recipient site plus is 1mm less in diameter than the donor site hole. The position of the plug was maintained at the correct articular cartilage level providing a utilising a press fit technique specially designed for this purpose. Assessment of the donor sites was made by MRI analysis at the time of review.

Results                 

Of the four patients in which the donor site was not reconstructed two had anterior knee pain and crepitus during activities at follow up. One patient in which a lateral retinacular release was performed at the time of initial surgery was pain free. Another two underwent a subsequent lateral release. Although their symptoms improved they continued to be symptomatic. Of the 18 patients in which reconstruction of the donor site was performed no patient had any anterior knee pain or donor site morbidity at review up to final follow up (3-14 months.).

MRI analysis of the donor site revealed full incorporation of the plug with no underlying subchondral high signal. The articular surface had been reconstituted albeit with a decreased thickness of articular cartilage.

Conclusion          

OCT is associated with a high degree of donor site morbidity. Lateral release did not appear to be effective in alleviating this problem. Reconstruction of the donor site using a correctly positioned press fit and stable recipient plus eradicated any donor site morbidity and on MRI analysis incorporated completely and provided an adequate articular cartilage surface. This avoidance of donor site morbidity allows for the extension of the technique for some of the larger type of defects.

Scott F. Dye, M.D

KNEE AS ORTHOPAEDIC ROSETTA STONE

  Associate Clinical Professor of Orthopaedic Surgery

University of California, San Francisco

Click here for the PowerPoint presentation

Careful observation of the injured and healing knee can lead to an understanding of basic biologic principles that may provide broad insights applicable to other joints and musculoskeletal systems of orthopaedic interest.  One may logically assume that biologic processes, such as the development of post-traumatic arthrosis that can be defined and ultimately controlled at the cellular and molecular level in the knee, should also be true for other musculoskeletal components.  The sports medicine oriented knee surgeon is uniquely positioned to provide such insights. 

The knee is the largest of human joints, and is readily examined, imaged (both structurally and metabolically) and arthroscopically inspected.  Conditions and injuries can be tracked from inception to full healing or to the development of degenerative changes.  Work already published by Daniels, Wojtys, and others, including this author, have begun to shift the paradigm that underlies most orthopaedic treatment from a purely structural/biomechanical perspective to one that also includes more subtle biologic factors such as the achievement of tissue homeostasis.  This new biologic perspective has resulted in a new concept of joint function characterized by load/frequency distribution (The Envelope of Function) that defines a range of load transference that is compatible and even inductive of tissue homeostasis of a given joint or musculoskeletal system.

We knee surgeons and scientists can also serve as orthopaedic theorists (and perhaps even philosophers), leading to the development of concepts that may well ultimately advance the entire field. 

  Ejnar Eriksson,

A PROSPECTIVE RANDOMIZED STUDY OF THE USE OF A BRACE IN SLIGHT HYPEREXTENSION VS. A STRAIGHT BRACE IN THE IMMEDIATE POSTOPERATIVE PERIOD AFTER ACL RECONSTRUCTION. 

Authors:  Christina  Mikkelsen, Giuliano Cerulli, Mikela Lorenzini and Suzanne Werner

·         The Hypothesis - What is the question?

A flexion contracture with a difficulty to extend the knee fully is one of the most cumbersome complications of ACL surgery.  At the ACL Study Group meeting in Rhodes, Greece, we reported about an X-ray Study which showed that if the knee is placed in a straight brace after surgery, it is lying in between 3º and 7ºof flexion.  A brace in -5º to -10º was needed to get all bandaged knees straight or into hyperextension.  Our question was, therefore:  Could a brace in -5º of hyperextension prevent flexion contracture after ACL reconstruction.

·         Method – How was the question investigated?

In a prospective randomized study every second patient operated with an arthroscopic PT BTB reconstruction was placed in a straight brace (Albrecht Hypex® brace) and every second patient placed in this brace set at -5º for 3 weeks post operatively.  They were allowed to take off the brace during exercise training but slept with it.  The amount of discomfort was measured the day before and 24 hours after surgery in both groups using VAS.  Range of motion was measured before and 3 months after surgery using goniometers and by measuring the difference in heel height in prone position.  Sagital laxity was measured before and 3 months post surgery using KT-1000 at “manual max.”  The physical therapist that analyzed the end results was blinded to which type of brace the patients had worn.

Results – What were the results?

There was no statistical difference in postoperative discomfort between the two groups.  Neighter was there any difference in sagital laxity between the two groups.  In the group with a straight brace, 12 out of 22 had more than 2º  of flexion contracture and in the group with the brace set in hyperextension 2 out of 22 had the same finding (p<0.01).  There was no difference in the amount of flexion of the knee between the two groups. 

· Conclusions:

The use of a post operative brace set in slight hyperextension seems to be an easy way of preventing flexion contracture after arthroscopic ACL reconstruction.  No side effects of the brace were noted.    

Julian Feller,

Bioabsorbable versus metallic tibial fixation in ACL reconstruction: a clinical and radiographic study

 Kate Webster, Kate Hameister

La Trobe University Musculoskeletal Research Centre, Melbourne, Australia 

Purpose: To compare the clinical outcome and extent of radiographic tunnel widening in four groups of patients who had undergone ACL reconstruction using either bioabsorbable or metallic devices for tibial fixation of patellar tendon and hamstring tendon autografts.

Methods: 133 patients underwent primary arthroscopically assisted single incision ACL reconstruction using either a middle third patellar tendon graft (PT) or a doubled semitendinosus/doubled gracilis hamstring tendon graft (HS). In all patients femoral graft fixation was by means of an EndoButton secured to the graft with a doubled 3mm polyester tape. Tibial graft fixation was by means of a PLLA bioabsorbable interference screw in 37 PT patients (PT-BIO) and 34 HS patients (HS-BIO), a metallic interference screw in 29 PT patients (PT-MET), and a metallic fixation post and non-absorbable sutures in 33 HS patients (HS-MET). The groups were well matched for age, sex, time to surgery, and associated pathology. The majority of injuries had occurred during Australian Rules football and netball. Post operatively patients undertook the same standard “accelerated” rehabilitation protocol. Patients were reviewed at 12 months when the following variables were recorded: general knee pain, anterior knee pain, pain on kneeling, active and passive flexion and passive extension deficits, KT-1000 side to side difference in anterior knee laxity at 15 and 30 pounds, IKDC and Cincinnati scores. Radiographic bone tunnel widening was also assessed by measuring the widths of the tibial and femoral tunnels in both anteroposterior (AP) and lateral views. Data were analysed using one way ANOVA with post hoc comparisons and Chi squared contingency tables.

Results: Generally there were few clinical differences between the groups. Kneeling pain was more frequent in the PT groups than the HS groups and more severe in the PT-BIO group compared to the HS-BIO group. Passive flexion deficits were greater in the MET groups than in the BIO groups. Anterior knee laxity at 15 pounds was greater in the HS-MET group than in either of the PT groups. Overall, all groups had a good outcome with mean Cincinnati scores between 84 and 89. The major differences between the groups were in the radiographic findings, which are shown in the Table. 

Table: Mean (SD) tunnel widening (%)

On both AP and lateral views the mean tibial tunnel widening was greatest in the HS-BIO group followed by the HS-MET, PT-BIO and PT-MET groups in descending order. There was no significant difference between the HS-MET and the PT-BIO groups.  For the femoral tunnel there was significantly greater widening in the HS groups compared to the PT groups. Within each graft type there was no difference between BIO and MET fixations except for the AP view of the HS group where there was increased widening in the MET group compared to the BIO group.

Conclusion: Although there was little clinical difference between the BIO and MET groups, the apparent increased tibial tunnel widening in the BIO groups should be noted and monitored in the longer term as a possible cause for concern in relation to both graft function and revision surgery. Use of a fixation post for HS grafts was associated with less tibial tunnel enlargement than use of a bioabsorbable interference screw but tibial fixation of HS grafts appears to remain an issue warranting further development.

 C.B. Frank

STRUCTURE-FUNCTION RELATIONSHIPS IN HEALING LIGAMENT SCARS

McCaig Centre for Joint Injury and Arthritis Research, University of Calgary, Calgary, Alberta, Canada

INTRODUCTION

      The combined approach of measuring biomechanical in addition to morphological and biochemical changes in healing ligaments has been our strategy for understanding and potentially optimizing the ligament healing process.  In addition to high-load properties such as failure strength, viscoelastic properties such as creep are also critical for understanding the functional role of healing ligaments.  For example, excessive creep or the “stretching out” of healing ligaments could contribute to joint dysfunction by causing abnormalities in joint kinematics.

METHODS

      We study a well characterized animal model in which a standardized length of bridging ligament scar is isolated and quantified using multiple techniques.  By removing a small midsubstance segment, an acute 4 mm gap is created in the medial collateral ligaments (MCLs) of one-year-old female New Zealand White rabbits.  Our mechanical testing protocol includes creep testing (measuring elongation under cyclic and static loading) and failure testing.  We also perform biological and morphological analyses: water content, glycosaminoglycan (GAG) content, collagen concentration, collagen cross-linking, collagen fibre alignment, collagen fibril diameters, and flawed areas of matrix.

RESULTS

      The total creep strain of the scars was found to be significantly greater than normal ligaments.  Although the scar creep strain decreased over the 3, 6, and 14 week healing intervals, at 14 weeks scar creep was still two-fold greater than normal.  The failure strength of the scars was significantly less than normal ligaments.  Despite some improvement with healing, by 14 weeks scar strength was around 30% of the normal ligament failure strength.

      Water content was abnormally elevated in the scars but decreased to normal values by 14 weeks.  GAG (hexosamine) content of MCL scars decreased with healing but remained elevated compared to normals at 14 weeks.  MCL scar collagen (hydroxyproline) concentration was observed to increase with healing back to normal levels by 14 weeks.  MCL scar collagen fibre alignment towards the long axis of the ligament improved with healing and equaled normal values by 14 weeks.  MCL scar collagen fibril diameters were significantly smaller than in control MCLs at all healing intervals (3, 6, and 14 weeks) and fibril diameters did not change over the 14 week healing interval.  MCL scar collagen crosslink (hydroxylysylpyridinoline) density increased with healing but reached only 55% of normal values by 14 weeks.  The mean total area of flaws (blood vessels, fat cells, hypercellular areas, loose matrix and/or disorganized matrix) as a percentage of total section of MCL scar was found to decrease with healing but was still larger than control values at 14 weeks.

DISCUSSION

      These results show that despite some improvement with healing, ligament scars clearly remained inferior to normal ligaments in terms of their ability to resist creep at comparable stresses.  Likewise, the failure strength of scars was significantly and persistently decreased compared to normal values.

      Several biochemical and morphological parameters were also changing as the ligament healed.  Elevated water content does contribute to increased creep but the magnitude of the water content change in these scars would only account for half the magnitude increase in creep so other factors must have a role.  With GAG content elevated, the ratio of bound to free water may be changed which may increase creep.  Water and GAG content likely have important roles in the viscoelastic properties but the collagen characteristics may also affect the viscoelastic in addition to the failure properties.  These initially poorly aligned scar collagen fibres never increase in diameter and may never make the spatial connections required to restore normal fibre architecture.  These abnormalities would cause poorer collagen fibre recruitment.  Inferior fibre recruitment would lead to ineffective stress redistribution over the available fibres and scar collagen fibres that were recruited would be carrying more stress, the resultant effect would cause decreased resistance to creep at lower stresses and decreased resistance to failure at higher stresses.  These collagen fibre inferiorities are further exacerbated by flaws in the matrix.  Flaws create stress concentrations, and thus the scar may creep more and fail faster because of increased stress local to the flaws.

      These unique results showed that sustained and repetitive stress caused creep of rabbit MCL scars.  Ligament scars were still more susceptible to creep and to failure than normal MCLs even after 14 weeks of healing.  Several possible biological mechanisms were implicated for these biomechanical inferiorities: increased water content, deficiencies in collagen fibre properties that affect fibre recruitment, elevated GAG content and flaws in the scar tissue.  Treatments aimed at altering these abnormalities may improve ligament scar creep and thus prevent the “stretching out” of healing ligaments.

Fukuda, Y.

Resultant force in the lateral meniscus and bony contact in the intact and ACL-deficient knee by applying valgus torque.

, Tsuda, E., Loh, J. C., Debski, R. E., Fu, F. H. and Woo, S. L-Y.

Musculoskeletal Research Center, Department of Orthopaedic Surgery

                              University of Pittsburgh, Pittsburgh, PA

The Hypothesis - What is the question?

            An excessive valgus torque is thought to be a mechanism of ACL injury associated with lateral meniscal tears.  However, the mechanism has not been elucidated.  When a valgus torque is applied, the lateral compartment of the joint compresses and the slope of the tibial plateau causes anterior tibial subluxation in the ACL-deficient knee.  The forces in the lateral compartment are shared between the lateral meniscus and femorotibial joint.  Therefore, the objective of this study was to determine the effect of valgus torque on the force distribution between these two components.

            We hypothesized that the force distribution in the lateral compartment will shift to the lateral meniscus as a result of ACL-deficiency in response to a valgus torque since the significant coupled anterior translation and internal rotation of the tibia occurred during the valgus torque in the ACL-deficient knee.

Method How was the question investigated?

Seven human cadaveric knee specimens were tested using the robotic/universal force-moment sensor testing (UFS) system.  The path of passive flexion-extension of the intact knee in five degrees of freedom (DOF) was first determined from full extension to 90º of knee flexion.  Then, a valgus torque up to 10 N-m was applied to the knee at full extension, 15°, 30°, 45° and 90° of knee flexion and the resulting 5 DOF knee kinematics were recorded.  The ACL was then transected under direct visualization through a medial parapatellar arthrotomy and the robotic manipulator repeated the previously recorded positions of the intact knee, while the UFS measured the new forces and moments.  The vector difference in force before and after ACL transection represents the in-situ force in the ACL by the principle of superposition.  The valgus torque was also applied to the ACL-deficient knee and the resulting changes in coupled anterior tibial translation (ATT) and coupled internal tibial rotation (ITR) were recorded. Next, a lateral meniscectomy was performed and previously recorded positions of the intact and ACL-deficient knee were repeated to determine resultant forces in lateral meniscus (LM) for intact and ACL-deficient.  Lastly, all soft tissues were removed and the bony contact forces in the intact and ACL-deficient knee were measured.

            The data obtained included the 5 DOF kinematics of the intact and ACL-deficient knee, as well as the resultant force in the LM and bony contact force in response to a 10 N-m of valgus torque.  These data were analyzed using a repeated measures analysis of variance with multiple contrasts.  The significance level was set at p<0.05.

Results What were the results?

-Data

At 15° and 30° of knee flexion, the force in the LM of the ACL-deficient knee significantly increased both by 12 N compared to that of intact knee.  There were no significant differences between the force in the LM of intact and ACL-deficient knee at 0°, 45° and 90° of knee flexion.  With regards to the bony contact, this force in the ACL-deficient knee significantly decreased by 9 N, 17 N and 20 N at full extension, 15° and 30° compared to that of intact knee.  Additionally the bony contact force in the ACL-deficient knee was not significantly different than that of intact knee at 45° and 90° of knee flexion.

Conclusions

            From our results, we confirmed our hypotheses that the force distribution of the lateral compartment shifted from the bony contact to the lateral meniscus in the ACL-deficient knee.  These scientific findings indicate that the excessive valgus torque might results in a lateral meniscal injury associated with acute ACL rupture.  Our future direction is to investigate that the mechanism of the ACL and lateral meniscal injury in combination with the medial collateral ligament by applying the valgus torque.

James N. Gladstone,

Evaluation of the sensitivity of 3D-SPGR MRI sequence to detect articular cartilage lesions of the knee, with a focus on ACL injured knees

 MD, Joshua Auerbach, Michael Bromley, MD, Sandra L. Moore, MD

·         The Hypothesis - What is the question?

Chondral lesions have been reported in 10-70% of ACL tears, the incidence increasing with chronicity of the injury.  In the last five years, advances in articular cartilage repair techniques, including microfracture, osteochondral autograft transplantation and autologous chondrocyte implantation, have led to more optimism in treating this challenging problem.  It therefore stands to reason that recognition of a chondral defect prior to surgery could help both surgical planning and patient counselling.  Until now, the only accurate means for determining chondral defects in the knee has been arthroscopy.  Increasing magnet strength and a better understanding as to how to sequence for articular cartilage with magnetic resonance imaging (MRI) has improved our abilitity to evaluate the articular surface of the knee.  There are few reports, and they vary widely, with regard to the sensitivity of MRI for detecting chondral injuries (18-95%).  The purpose of this study was to evaluate the accuracy of a cartilage specific MRI sequence (3D-SPGR) for detecting chondral lesions in the knee, and in particular in those knees with ACL tears.

·         Method – How was the question investigated?

At our institution, for the last two years, every knee MRI has included a 3D-SPGR sequence that has been read by a fellowship trained musculoskeletal MRI radiologist.  All patients who had undergone knee arthroscopy by the same sports medicine trained orthopaedist, and preoperatively had an MRI at our facility were included.  95 patients comprised this study, 14 of them undergoing ACL reconstruction at the time of surgery.

Preoperative articular cartilage findings were correlated with findings at arthroscopy.  The knee was divided into 6 regions: patella, trochlea, medial femoral condyle (MFC), medial tibial plateau (MTP), lateral femoral condyle (LFC) and lateral tibial plateau (LTP).  Extent of chondral injury was graded by the modified Outerbridge classification (I-IV).  MRI’s sensitivity, specificity and accuracy was determined for each region and each grade of injury.

·         Results – What were the results?

The findings for the study group as a whole are shown in Tables 1 and 2.

546 articular surfaces were evaluated. Arthroscopy revealed 144 chondral lesions. MRI detected 49 lesions.

Table 1: Chondral lesions by grade

Table 2: Chondral lesions by site

The ACL group had 7 chondral injuries (2 patients had two injured regions) detected at arthroscopy, with only 3 seen on MRI. 3D-SPGR also detected 7 defects that were not supported by arthroscopy.  This group had a sensitivity of 43% and specificity of 92%.

·        Conclusions

 We were both disappointed by the limitations of the 3D-SPGR sequence to pick up articular cartilage lesions in the knee.  Our results are in the mid-range of those reported in the literature with varied sequences.  We were surprised by our results.  Most of the MRI’s had been reviewd by both the radiologist and the orthopaedist together, and on a case by case basis we had been impressed with the sequence’s ability to clearly show fissures, flap tears, partial- and full-thickness tears in the chondral surface.  The one grade of injury that we found difficult to visualize was the grade III, crabmeat-like lesion.  We are currently performing a retrospective review of the MRIs to try to determine whether the interpretation or the sequence was the cause of the low sensitivity findings.  We are also evaluating whether an Outerbridge classification can be applied to MRI findings or rather a “clincally relevant (grades II and IV) versus irrelevant (grades 0, I and II)” classification should be used.  Finally, we are planning a prospective study to compare 3D-SPGR with fast spin echo with high resolution matrix, the other commonly used cartilage sequence.

E. MARLOWE GOBLE, M.D

CROSS PINNED INTERFERENCE SCREW

.

Interference screw fixation for bone-tendon-bone grafted anterior cruciate ligament reconstruction is the most common method for fixating the graft, especially the tibial side.  Interference screw fixation is almost always adequate for primary cases in young athletes.  However, when bone density is decreased, either from advancing age or revision ACL cases, interference screw fixation can be inadequate if the patient is exposed to immediate rigorous knee rehabilitation.

Interference screw fixation can be significantly augmented by “cross pinning” the interference screw/bone plug complex.  The average ultimate loads for cross-pinned interference screw system and the traditional interference screw systems were

819_ 221N and 544  131N, respectively. 

Cross-pinning a traditional interference screw adds 30 seconds to the case, and virtually eliminates bone plug interference screw dislodgment. 

Charles A. Gottlob, MD

BIOABSORBABLE INTERFERENCE SCREW FIXATION OF HAMSTRING ACL GRAFTS:  THE EFFECT OF SCREW DIAMETER ON PULL-OUT STRENGTH

 and Otto Schueckler, MD

                                                Guest of Dr. Eric Stahl

Purpose:  The purpose of this study was to determine the effect of screw diameter on the insertional torque, mode of failure and pull-out force of quadrupled hamstring tendon grafts when secured with a bioabsorbable interference screw.  A previous study has shown increased pull-out strength with increased screw diameter and length.  Other studies have shown an inconsistent relationship between insertional torque and pull-out strength.

Methods and Materials:  The semitendinosus and gracilis tendons were harvested from (30) fresh cadaveric specimens.  All specimens were prepared and looped to form a four limb graft.  The graft was then fixed to a standard block of polyurethane foam through an 8 mm tunnel with either a 7 mm x 28 mm (Group I), 8 mm x 28 mm (Group II) or 9 mm X 28 mm (Group III) Bio-Interference Screw (Arthrex Corp., Naples, FL).  Insertional torque was measured.  Grafts were loaded to failure on an Instron machine  Failure was defined as loss of fixation or greater than 5 mm of graft slippage.  Peak force and mode of failure were recorded.  Results were analyzed with Anova and Newman-Keuls tests. Results wee also subjected to a power analysis.

Results:  Average insertional torque measured 0.67Nm (Group I), 1.02Nm (Group II), 1.27Nm (Group III).  Anova testing showed statistical difference at a p<.0000001.  Average pull-out measured 340 N (Group I), 371.1N (Group II), 426.7N (Group III).  Anova showed no statistical difference.  All grafts failed by slippage.  No grafts were severed by the screw.  Power analysis showed adequate sample size and no difference between the pull-out at the 80% level.

Conclusion:  Insertional torque was positively affected by increased screw diameter, whereas pull-out strength was not.  Screw diameters within 1mm of  the reamed tunnel size provide similar pull-out strengths.  

P. Hertel,  

SECONDARY TENSIONING OF AN ELONGATED ACL GRAFT

T. Cierpinski, S. Mundin

Martin-Luther Krankenhaus, Unfallchirurgie, Caspar-They§-Str.27, 14197 Berlin, Germany

QUESTION

Is secondary tensioning of an elongated ACL graft justified?

In spite of anatomical knowledge and use of correct insertion areas in ACL reconstructions graft elongation occurs in a certain percentage of patients.  The reason may be unrecognized loosening directly to the first period of rehabilitation or “idiopathic” changes in ligament behavior.  Is it possible to tension loose ACL grafts with correct anatomical insertion?

METHOD

24 patients have been tensioned during a period of 8 years.  3 patients could not be traced, 3 lived far.  12 of 24 came back for a follow up investigation:  7 women, 5 men.  Most of them had primary BTB ACL replants.

7 patients had a tibial tensioning by segmental slide after cutting a wedge from the anterior tibial plateau including the ACL graft insertion area, 5 patients had a tibial tensioning by cylindrical slide.

RESULTS

No third reconstruction was done.  Motion was generally unchanged.  Stability changed from KT1000 MMT pre-op 8, 1 mm (diff.) to posto-op 2,7 mm (diff.)  Subjectively, patients felt more stable and estimated the operation as successful.

CONCLUSION

In case of correct insertion and mechanical stability of ACL transplants, it is justified to tension ACL grafts distally either by segmental or cylindrical slide.

Christian Hoser, MD  

Correlation of the injury pattern and a videoanalysis of anterior cruciate ligament tears in world cup alpine ski racers

Coauthors: Christian Fink, Karl Peter Benedetto, Werner Nachbauer

University Hospital Innsbruck, Dept. of Traumatology

Academic teaching Hospital Feldkirch

University of Innsbruck, Dept. of Sports Sciences

  Introduction:

Anterior cruciate ligament rupture has been the most frequent serious injury in world cup skiers for many years. The advent of new equipment, the so called „carving ski” is said to have even increased the incidence in recent years. Significant regulations have been put in place regarding ski geometry and ski-foot distance in order to prevent serious injuries. This study intends to provide information for further preventive measures.  

Methods:

We collected video sequences of 15 incidences during ski racing or training, where a racer sustained a confirmed ACL rupture. Subsequently we contacted the treating physician or athlete to obtain operative reports, x rays and MRI reports and/or images .

We listed all concomitant injuries to the ACL rupture such as meniscal tears, additional ligament injuries, joint cartilage injuries, bone bruises and fractures.

The videoanalysis was performed to estimate the rotational moments and forces that lead to the injury as well as to record the knee angle in the sagittal and the frontal plane at the time of injury. Additionally special emphasis was placed on the position of the ski with regards to “a carving type” action.

Results:

We found that videoanalysis alone was not able to detect the moment of ACL rupture in half of the cases. In some cases one could even not be sure as to which knee was injured. In the other half it was clearly detectable when the rupture occurred. The knee angle in the sagittal and frontal plane at the time of injury differed widely.

MRI analysis gave a clear picture with regard to injury mechanism in one third of all athletes. Combining both sources of information made it possible to pin point the time of injury and define the injury mechanism in another third. One third showed an injury pattern that could not be explained by a single twisting event and might be caused by two or even more injury causing events that happened during the fall.

Conclusions:

The combination of videoanalysis and injury pattern analysis gave us new insight into the damage causing moments of an anterior cruciate ligament injury. It may be of value to those who are responsible for the regulation of skiing equipment in racing. Furthermore it helps in the development of new type safety bindings.

 Stephen Houseworth, M.D., F.A.C.S

Use of Allograft Osteochondral Transfer (OATS) and Allograft Lateral Meniscus to restore the Lateral Compartment in an ACL Deficient Knee.

HYPOTHESIS:  The use of an allograft OATS graft to the lateral tibia combined with an allograft lateral meniscus transplant effectively restored function and stability to an otherwise unstable and poorly functioning knee.

METHOD:  This is a case report of a 43 year old male who had presented to my clinic 7 months after sustaining a closed, comminuted, lateral tibial plateau fracture and ACL tear in a dirt bike accident.  A previous surgeon only performed and open reduction but no internal fixation to the fracture and had removed the entire lateral meniscus.  The patient presented to my clinic with range of motion 20 –103 degrees and 19 degrees of genu valgum.  I performed an ORIF with extensive bone grafting to a non-union of the proximal lateral tibia as well as arthroscopic debridement and open posterior capsular release.  This procedure allowed for bony union of the fracture but failed to gain further range of motion. 

Follow up x-rays and repeated CT scan noted recurrent collapse of the anterior lateral tibial plateau.  After much preoperative planning I performed an allograft OATS procedure to the anterior lateral tibia using a 35-mm diameter, 35-mm depth, fresh frozen graft from a medial femoral condyle and simultaneous allograft lateral meniscal transplant, arthroscopic debridement and repeat open posterior capsular release.  The exposure to the lateral tibia was facilitated by the absence of the ACL.  The ACL was not reconstructed.

RESULTS:  At 18 months post-op the patient is pain free and walks with a slight limp.  His knee range of motion is 10-120.  His knee remains stable with 3-mm side to side KT-2000 findings.  His follow up weightbearing x-rays note normal contour of the lateral tibia and normal lateral joint space.  He wishes to return to skiing.

CONCLUSIONS:  In this unusual and complex case the use of a large, fresh frozen allograft OATS graft combined with lateral meniscal allograft transplantation successfully restored the integrity of the lateral compartment in an ACL deficient knee.  

Stephen M. Howell, MD

Guidelines for Tibial and Femoral Tunnel Placement in the Coronal Plane that Minimize Anterior Cruciate Ligament Graft Tension in Flexion and Impingement Against the Posterior Cruciate Ligament: A Study in Cadaveric Knees

Richard Simmons, MS;  and M. L. Hull, PhD

Biomedical Engineering Program, Department of Mechanical Engineering

University of California, Davis, CA, USA 95616

Background: It has been stated that the outcome of anterior cruciate ligament reconstructions might be improved if the tension in the graft replicates the tension of the intact anterior cruciate ligament. Clinical observation of femoral tunnel placement during arthroscopy suggested the possibility that controlling the angle of the tibial and femoral tunnel in the coronal plane might reduce impingement of the graft against the posterior cruciate ligament in flexion and result in a more normal pattern of graft tension in flexion.

Methods: The effects of the tibial tunnel angle (60, 70, and 80 degrees), femoral tunnel angle (60, 70, and 80 degrees), and incremental excision of the lateral edge of the posterior cruciate ligament (2 mm increments) on the flexion angle at which graft tension increases and on graft tension at terminal flexion were studied using fresh-frozen, human, cadaver knees in a computer controlled, six-degree load-application system.

Results: The 60 degree tibial tunnel and 60 degree femoral tunnel resulted in the most normal pattern of graft tension, and the 80 degree tibial tunnel and 80 degree femoral tunnel resulted in the most abnormal pattern of graft tension in flexion (p = 0.0001). The femoral tunnel angle affected the pattern of graft tension greater than the tibial tunnel angle (p < 0.05). Incremental excision of the posterior cruciate ligament lessened impingement of the anterior cruciate ligament graft and resulted in a more normal pattern of graft tension in flexion (p = 0.0001).

Conclusions: Placing the femoral tunnel angle in the coronal plane at 60 degrees, which moves the graft laterally and reduces impingement of the anterior cruciate ligament graft against the posterior cruciate ligament, results in a more normal pattern of graft tension in flexion.

Clinical Relevance: Surgeons that use the single-incision technique, and drill the femoral tunnel through the tibial tunnel, should place the tibial tunnel angle at 60 degrees in the coronal plane. Surgeons that use the single-incision technique, and drill the femoral tunnel through the anteromedial portal, should place the femoral tunnel angle at 60 degrees in the coronal plane; the tibial tunnel can be placed at any angle between 60 and 80 degrees.

Chris Kaeding MD

The Effects of Radiofrequency Treatment on Chondrocytes and Articular Cartilage Matrix of Fibrillated Cartilage

Anne Ryan MD*, Alicia Bertone DVM, PhD+ *

*Department of Orthopaedics, +College of Veterinary Medicine,

The Ohio State University, Columbus, Ohio

Abstract

Introduction (Objective)- The purpose of this study was to determine

whether commercially available radiofrequency probes used in arthroscopic surgery have detrimental effects on articular cartilage chondrocytes.  Chondrocyte well being was determined by examining proteoglycan metabolism, cell viability and tissue morphologic changes associated with three different energy settings and a control.

Methods- Paired patellae from 11 horses between the ages 2 weeks and 20 years were harvested and the surface of each was divided into 3 sites.  Fibrillation of patellae was created with a bone rasp to mimic clinical fibrillation. One patella served as a fibrillated articular cartilage control (Gp 1).  The contralateral patellae were treated at each of the 3 sites with one of 3 different energy settings (20 [Gp 2], 40 [Gp 3], or 60 [Gp 4] watts) for 4 minutes at each site in a paintbrush pattern under arthroscopic guidance.  Surface articular cartilage temperature was measured with the patellae submerged in arthroscopic fluids at each energy setting. Cartilage explants (in duplicate) were immediately harvested and incubated for 24 hours at 37 degrees Celsius and 95% humidity.   Proteoglycan synthesis (Na³⁵SO₄ incorporation for 24 hours), proteoglycan degradation (Na³⁵SO₄ release for 72 hours) and cell viability (0.2% Trypan blue exclusion stain) were measured. Explant histologic sections were scored for cellular characteristics, metachromatic matrix staining intensity, and tissue architecture. Sections were quantitatively analyzed for cell death (% empty lacunae). Quantitative data were analyzed with a two-way ANOVA for group and energy setting.  Histology data was evaluated with both ANOVA and the Mann-Whitney U Test.  Significance was set at P<0.05.

Results- Mean peak surface articular cartilage temperatures were 35.7^oC (96.3°F), 41^oC (105.8°F), and 45.5^oC (113.9°F) for Gp2, Gp3, and Gp 4, respectively. Radiofrequency applications at all three settings significantly decreased proteoglycan synthesis of the chondrocytes as compared to controls. Increasing radiofrequency energy setting decreased proteoglycan synthesis further among treatment groups.  Proteoglycan degradation increased with increased energy setting such that radiofrequency settings of 40 and 60 Watts had significantly greater degradation than the 20 Watt treatment group or the controls.  Increasing energy also decreased cell viability in higher energy groups.  Control cartilage cultured for 7 days had 89% viability.  Radiofrequency treatment at 40 and 60 Watts significantly decreased viability to 81% (p=0.059) and 73% (p=0.001) respectively.

Conclusion- Radiofrequency treatment of cartilage has immediate suppressive effects on chondrocyte metabolism at all power settings.  Cell viability and proteoglycan synthesis decreased and proteoglycan degradation increased with increased power settings.  Based on this ex vivo model of fibrillated cartilage, cautious use of radiofrequency energy treatment of cartilage is recommended until studies evaluate more long term in vivo effects of radiofrequency energy treatment of cartilage.

INTRODUCTION

The anterior cruciate ligament (ACL) is an important structure in controlling knee joint stability. ACL injuries disrupt the delicate balance of knee structures and may affect knee functional activities. ACL deficient subjects may reprogram their muscle activations and alter knee kinematics to compensate for the injury. Development of the compensatory mechanism is closely related to the role of ACL in stabilizing the knee. Although it seems clear that ACL is loaded in strenuous activities like inward cutting and running^2,3, it is not clear whether the ACL is loaded during moderate activities like walking and whether compensation is needed. Considering the essential importance of walking, it is important to evaluate ACL loading during locomotion and better understand the compensatory mechanisms. The purpose of this study was to evaluate the ACL strain during simulated walking using a cadaver model, with the knee placed at various axial rotation and anteroposterior translation positions.

METHODS

Fresh frozen knee specimens were used to evaluate ACL strain during walking. After exposing the ACL through a parapatellar incision on the specimens, a MicroStrainä DVRT transducer was sutured onto the anteromedial band of the ACL with appropriate initial positioning. The femoral intercondylar notch was enlarged to avoid potential impingement of the DVRT against the intercondylar notch¹. After closing the cut, the knee specimen was mounted onto an experimental apparatus (Fig. 1). The femur was fixed rigidly to the frame. The tibia was fixed to an attachment mechanism, which was driven by a servomotor. The tibial attachment mechanism provided adjustment of tibial abduction, flexion, axial rotation, and three orthogonal translations of the tibia relative to the femur. A six-axis force sensor was used to measure the forces and moments exerted onto the tibia, and precision potentiometers were used to measure tibial rotations and translations. A position sensor was placed on the patella to measure patellar tracking. Ropes were sutured to individual muscles crossing the knee (vastus medialis oblique, vastus medialis longus, vastus intermedius, rectus femoris, vastus lateralis, gracilis, sartorius, semitendinosus, semimemberanosus, long and short heads of the biceps femoris, and IT band) through fiberglass mesh. Ropes and pulleys were used to load the muscles according to the muscle physiological cross sectional area. Only the ACL strain during simulated walking is analyzed here.

Average knee flexion pattern during free speed walking obtained from 30 normal subjects was used to control the servomotor and simulate walking on the cadaveric knee. About 13 “strides” were repeated in each 16 sec long trial. The test was repeated with the tibia placed at difference axial rotation (-7º, 0º, and 7º internal rotation) and anterior-posterior translation (-10mm, neutral, and 10mm) positions.

Figure 1: Experimental setup.

RESULTS AND DISCUSSION

The ACL strain varied systematically with knee position during the simulated “walking”. The ACL was loaded considerably during “free-speed walking” and the largest strain was observed at full knee extension (Fig 2). Furthermore, the ACL strain increased markedly with tibial internal rotation and anterior translation (Fig. 2). On the other hand, tibial external rotation and posterior translation reduced the ACL strain substantially (Fig. 2). Over a trial, the strain variation was usually larger during the first stride and became smaller and more repeatable afterwards.

Figure 2: ACL strain during simulated “free-speed walking” using a cadaver model. (a) Knee flexion as a function of stride %; (b) ACL strain during simulated “free-speed walking”, averaged over 48 strides. From top to bottom, the five curves represent the ACL strain with the tibia positioned at internal rotation (7º) plus anterior translation (10 mm), internal rotation (7º), neutral, external rotation (7º), and external rotation (7º) plus posterior translation (10 mm), respectively.

SUMMARY

The present study provided us a useful tool to evaluate ACL loading in well-controlled and systematically varied patterns. The cadaver setup also provided the flexibility of evaluating ACL strain under conditions that were difficult to implement in an in vivo setup (e.g., ACL strain at full knee extension). The results show that the ACL is loaded considerably during free-speed walking, indicating the need for compensation for ACL deficiency during locomotion. Since internal rotation of the tibia loads the ACL strongly⁴, one compensatory mechanism adopted by ACL deficient subjects is to externally rotate the tibia relative to the femur to avoid loading a partially torn ACL and/or to avoid unstable knee positions⁵. Further work needs to be done to test a larger sample at systematically varied knee positions in 3-D space.

REFERENCES

1.   Arms, S.W. et al. (1984). Am J Sports Med, 12, 8-18.

2.   Beynnon, B.D., Fleming, B.C. (1998). J. Biomech., 31, 519-525.

3.   Beynnon, B.D. et al. (1995). Am. J. Sports Med., 23, 24-34.

4.   Markolf, K.L. et al. (1995). J. Orthop. Res., 13, 930-935.

5.      Zhang, L-Q. et al. (1998). Gait & Posture, 7, 156.

M.L. Ireland,  

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 Differences in Core Stability between Male and Female

Collegiate Athletes as Measured by  Trunk and Hip Performance

D. T. Leetun, B. Ballantyne, I..S. McClay

• Hypothesis – Are deficiencies in trunk and hip muscular performance predictive

of lower extremity injury in collegiate basketball athletes?

• Method - Prior to the beginning of the organized season, a series of tests designed to measure core strength were conducted on 73 varsity collegiate basketball players, 49 female and 24 male.  Endurance time of the back extensor (BE) muscles was tested using a modified Biering-Sorensen test.  A side bridge (SB) test was used to measure endurance time of the lateral trunk flexors.  Subjects supported themselves on their flexed elbow as the hips and knees were lifted off of the floor.  The total time they were able to maintain this position was recorded.  Abdominal (AB) muscle performance was assessed with the straight leg-lowering test.  Subjects were positioned supine with their hips flexed 90° and knees fully extended.  Subjects then lowered the legs to the table in time with a metronome, keeping the lumbar spine pressed into the investigator’s hand.  The rate of leg lowering was approximately 9°/s.  Abdominal performance was recorded as the degree of hip flexion at which the low backs began to rise off the investigator’s hand.   A hand-held dynamometer was used to measure isometric strength for hip external rotation (ER) and abduction (Abd).  Abduction strength was measured with subjects positioned side lying with the hip slightly abducted.  The average of three trials was used in the analysis.  External rotation strength was measured with the subject sitting on a Biodex chair with the hip and knee flexed 90^o.  The average of three trials was used in the analysis for each isometric test.  Isometric force measurements were normalized to body weight for comparisons between individuals.

Throughout the season, athletic trainers recorded all lower extremity injuries.  An injury required that the athlete seek attention from the athletic trainer, team physician, or other medical staff and resulted in at least one day lost from participation in a practice or game. 

• Results – A total of 21 lower extremity injuries occurred over the course of the season (17 female, 4 male).  Ankle sprains accounted for 58% of all lower extremity injuries. Muscle performance measurements at the beginning of the season showed that males performed significantly better than females for all of the activities tested.

            BE            SB            AB            ER            Abd

Male            147.8 s            86.8 s            50°            .23            .34

Female               117.9 s    60.2 s    59°            .18     .29

Correlations among the various muscle performance measures are presented in the following table.

                                                Abduct    Ext Rot    Abdom.    Side 

Ext. Rot.    .64          

Abdom.    -.17           -.23     

Side                         .36           .58          -.32

Back                         .18          .33           -.31        .64

            Although no significant difference were found between injured and uninjured

athletes, there was a trend toward lower values of muscle performance in the

injured group.

                                                Abduct.     Ext. Rot.   Abdom.   Side        Back

                        Injured                 .28           .18       58.57       62            118

                        Uninjured            .32           .20       54.23       71            130

Student t-tests were used to compare muscle performance between males and females.  Pearson correlation coefficients were calculated to examine relationships among the various muscle performance measures. MANOVA was used to compare injured vs. uninjured for the dependent variables.

·        Conclusions – Males perform significantly better in measures of  trunk and hip performance.  Hip external rotation is significantly correlated with abduction strength and side bridge endurance.  Side bridging is also correlated with back extension endurance. Although trends toward lower values for hip and trunk muscle performance were seen in injured vs. uninjured athletes, further study is needed with larger samples.  At this time, the hip and trunk muscle performance did not show predictive value in determining risk of injury.

·      Relevance to ACL Injuries – No ACL tears occurred in this initial group. 

      Deciding on specific tests that assesses core stability is necessary.  The testing

      must be:  done anywhere with little equipment, time efficient, and enthusiastically

      done by the athlete.

Philipp Lobenhofer

Treatment of severe Arthrofibrosis

Despite all developments in minimal-invasive ACL reconstruction, a significant number of patients develop severe arthrofibrosis. Surgical treatment of this condition is still a challenge. Long-lasting flexion contractures cause fiunctional deficits, a bent-knee gait and secondary hip and spine problems. These patients are disabled and usually subject of multiple physiotherapeutic and arthroscopic treatment efforts with frustrating result. This paper presents a rationale for treatment of severe extension deficits caused by generalized arthrofibrosis as well as the cellular biological background for our surgical approach.

Technique: Prior to surgery, the patient is evaluated for mechanical factors causing motion deficits (intraarticular hardware, heterotopic ossifications, graft impingement, adhesions of the suprapatellar pouch). Cases with these problems are treated by appropriate arthroscopic or open techniques. Generalized arthrofibrosis is diagnosed with fixed motion deficits, contracture of the peripatellar retinaculae, painful fat pad und posterior capsule shrinkage (limited rotation in near-extension position). Stability and range-of-motion is carefully registered and subjective function is rated with a special score. A small anteromedial incision is made and two flaps are carefully created from the medial retinaculum. The fat pad and the pretibial bursa are exposed. The inner layers of the fat pad, the pretibial bursa as well as the medial and anterior synovial layer are regularly transformed to extremely dense white fibrous tissue. This tissue is radically excised. The intercondylar notch and the insertion area of the ACL are debrided. Extension is now usually improved but not complete and the inhibited terminal external rotation of the knee will be registered. A separate posteromedial skin incision of 5 cm length is created. The medial retinaculum is divided and the posterior capsule is exposed. The capsule is incised above the medial meniscus posterior horn and severe capsular fibrosis as well as adhesions of the posterior capsule to the condyles and the PCL are regularly found. The capsule is now dissected off the distal femur until no tension is felt in terminal extension any more. The medial gastrocnemius attachment is usually released at this time. Now full extension should be possible and the terminal external rotation of the tibia should be visible when the knee is guided to extension. If necessary, the suprapatellar recess is freed to improve flexion. Drains are inserted and the posteromedial retinaculum is closed without any reefing. The anterior incision is closed using the retinaculum flaps created at the beginning of the procedure. The leg is placed in a dynamic extension splint and active extension training is begun immediately. Full weight-bearing is usually permitted after 4 weeks.

Results: 121 patients with severe arthrofibrosis were treated with this technique from 1990 to 2000. A mean of 4 procedures were performed without success to recreate motion before the arthrolysis (maximum 12). The mean extension deficit was 20 degrees and the duration of fibrosis was up to 7 years. The increase of extension at last follow-up was 17°, no patient had more than 5° extension deficit. The AOSSM subjective outcome score was excellent in 30%, good in 50% and fair in 20%. No secondary instability was found. The only complications were two synovial fistulae requiring revision.

The specimens were subjected to extensive histological and immunological investigations. An abnormal high proliferation rate and vascularity of the synovial and subsynovial layer of the fat pad was registered. Pathological concentration of type VI collagen, of MHC-II compatible cells, macrophages and dendritic cells were found in this region. In contrast, the posterior capsule showed dense connective tissue without abnormality.

Conclusions: these patients have chronic and ongoing fibrosis of the anterior fat pad and the anterior synovia and subsynovial layers. We hypothesize a chronic autoimmunological process leading to progressive fibrosis and secondary shrinkage of the entire knee capsule. Our operative concept is relatively simple and has a considerable success rate.

D. McAllister,

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Response of tibial tunnel and tibial inlay posterior cruciate ligament graft reconstructions to cyclic loading.

 K. Markolf, and J. Zemanovic

UCLA Department of Orthopedic Surgery

Introduction: Excessive post-operative posterior laxity is often observed in patients who have undergone PCL reconstruction with a tibial tunnel. With the tibial inlay technique, graft fibers are loaded in a more physiological fashion, which could potentially avoid residual laxity related to the tibial tunnel.  The purpose of this study was to compare the mechanical responses of B-PT-B allografts to cyclic loading tests using tibial tunnel and tibial inlay PCL reconstruction techniques.

Methods:  The proximal ends of 31 tibial tunnel and 31 tibial inlay graft reconstructions were subjected to 2000 cycles of tensile force from 50 to 300 N.  Fresh frozen B-PT-B grafts were secured to a potted tibia using the tunnel or inlay reconstruction technique.  Measurements of graft thickness were taken at the point of highest anticipated tissue deformation.  The total change in graft length at an applied force level of 200 N was recorded after cyclic loading.  RANOVA was used to compare all measurements between inlay and tunnel reconstructions.

Results:  10/31 tibial tunnel reconstructions failed at the killer corner before 2000 cycles of testing could be completed; all 31 inlay reconstructions survived the testing intact.  Results from the 21 pairs which survived testing with both reconstruction techniques:

Discussion and Conclusion:  The inlay technique of PCL reconstruction is superior to the tunnel technique with respect to graft failure, graft thinning, and permanent graft elongation.  

Gianluca Melegati,

The Role Of Rehabilitation Brace In Restoring Knee Extension After Anterior Cruciate Ligament Reconstruction

 Davide Tornese, Marco Bandi, Piero Volpi*, Matteo Denti*

Sports Rehabilitation Unit

*Sports Traumatology and Artroscopy Unit

Galeazzi Orthopaedic Institute – Milan

To evaluate the effects a rehabilitation brace locked in extension for the first week has on the recovery of full extension after ACL reconstruction we compared two groups of subjects who underwent ACL bone-patellar tendon-bone reconstruction.

In group A 11 subjects (mean age 29 +- 6,1 yr) wear a post-operative brace locked in full extension for the first week. The brace was unlocked  two times  a day for assisted physiotherapy.In Group B 11 subjects (mean age was 28,3 +- 4,7 yr.) wore the same post-op brace unlocked from 0° to 90°. In both groups the brace was unlocked (R.O.M. 0°-120°) at the beginning of the second postoperative week and than removed at the beginning of the third week. All the subjects followed the same accelerated, well controlled rehabilitation protocol.

Each subject has been evaluated as follows: pre-operative and post-operative (2^nd, 4^th, 8^th week) assessment of range of motion by goniometric and bubble-level measurements, quadriceps and hamstring isometric strength test at the 10^th postoperative week, KT 1000 arthrometric measurement at the 4^th postoperative month.

The results were statistically evaluated using the Wilcoxon paired rank test, confidence intervals (95%), descriptive statistics and ANOVA.

In subjects who underwent ACL patellar tendon-bone graft reconstruction the application of a rehabilitation brace in full extension during the first postoperative week was more effective in recovering full extension of the operated knee than the application of the rehabilitation brace unlocked in the ROM 0°-90°. There was no difference between muscle strength recovering and stability of the graft.

P Marks,

  "COMPARISON OF ONE‑LEG HOP FOR DISTANCE SCORES IN THE ANTERIOR CRUCIATE LIGAMENT DEFICIENT POPULATION WITH A GROUP OF HEALTHY CONTROLS"

  S C, O'Donnell, S.G. Thomas, B. Kirshner. The Centre for Studies of  Physical Function, Orthopaedic & Arthritic Institute, Graduate Departiiient of  RehabIlitation Science, University of Toronto Toronto, Ontario, Canada

·         The Hypothesis ‑ What is the question?

Background:

Clinicians use performance tests, such as the one leg hop for distance (OLRD), to assess the functional status of patients with an anterior cruciate ligament deficient (ACLD) knee, However, the. validity of the OLHD as a diagnostic tool for ACLD inquiries has not been properly evaluated.

Research Questions:

1) What is the impact of different sources of error on the validity  of the OLHD f‑or assessing

.ACLD injuries?

2) Upon minimizing the sources of error, what is the impact on. the sensitivity of the OLHD

scores in the assessment of ACL injuries?

·         Method ‑ How was the question investigated?

OLHD performance was evaluated in 10 males (18‑42) Years with an isolated.ACL tear (grade 2 or 3 ligamentous laxity) all requiring reconstructive surgery and 9 gender and age‑matched healthy, non‑Injured Controls and the diagnostic ability of the hop index in the assessment of ACL injuries was explored.

·         Results ‑ What were the results?

Data: Those ACLD subjects who hopped further on their non‑injured limb had significantly poorer hop index scores relative to those ACLD who did not hop as far on their non‑injured limb A similar finding was not observed in the Control group,

ACLD NON‑INJURED                     ‑ACLD INJURED                        CONTROLS

r=0.66, p=0.04*           r=0.10 ;‑ p=O. 79           r=0.32; p=0.40

Thus, the differences in hop distance scores become a critical  factor it) terms of the sensitivity of the hop index scores In the ACLD only .  Performing a data transformation (logic) improved the sensitivity of the hop index from 50 to 70"/'~ in the detection of an abnormal hop index within the , ACLD population by decreasing the effect of the numerical variation in the hop distances scores normal hop index  >  90%  i n a healthy male population). The specificity rate was high (100%) and unaffected upon performing the data transformation in the Controls.

·        Conclusions:

The further the ACLD subjects hopped on their  non‑injured limb, the more asymmetrical  their hop index thus, the distance hopped on the non‑injured limb is a critical factor  the sensitivity of the hop index in the ACLD population .Transforming  the hop distance scores minimizes the effect of the numerical variation of the underlying the hop distance scores and improves the sensitivity of the hop index in the assessment of ACL injuries.

  H.H. Paessler,

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Donor site morbidity after anterior cruciate ligament reconstruction with ipsilateral versus  

                                            contralateral harvesting of bone-patellar-tendon graft.

                                  Authors:   D.S Mastrokalos, E.K. Motsis, S. Mueller.

·         The Hypothesis - What is the question?

The aim of this study is the evaluation of the activity level and the remaining symptoms concerning the graft donor site in patients having anterior cruciate ligament reconstruction (ACL) reconstruction with either ipsilateral or contralatral bone-patellar-tendon (BPT) graft.

·         Method – How was the question investigated?

100 patients aged from 18 to 49 years (mean 34) having an ACL reconstruction with BPT-graft from 1997 to 1999 were included in this study. In 52 of them a BPT-graft (central third) from the ipsilateral side was used (group I). In 48 patients the contralateral BPT was used (group II). The BPT graft with a bone plug only from the tuberositas for femoral pressfit fixation was chosen to diminish additional morbidity by harvesting a bone plug from the patella. All patient were followed up by questionaire at an average of 35 months (25-53 months) postoperative. The questionaire included the Cincinnati score the Tegner activity score and special questions concerning persisting symptoms at the donor site such as tenderness, numbness, kneeling pain and pain while walking on the knees. For statistical analysis the paired t-test was used.

·         Results – What were the results? –Data -Statistical analysis

The time from surgery to uptake of sports acitivities were in both groups similiar. The average Cincinnati Scoring was 85,2 in Group I and 86,3 in Group II. There was no statistical significance in the Tegner score between the two groups. Impressive was that 88% of all the patients had complaints at the donor site such as paraesthesias and pain, when walking on their knees.

Within group II there were 3 major complications concerning the donor knee: 1 rupture of the patellar tendon, 1 severe tendinitis, resolved only by surgery, 1 chronic severe tendinitis which continued more than3 years postoperative.  No similiar ccomplications were observed in group I.

·        Conclusions

Donorside problems after harvesting the central third of the patellar tendon even with only one bone plug  seems to be an underestimated problem. This study showed that there are no benefits if the contralateral BPT graft is used. All major postoperatve  complaints concerns the harvesting side and are shifted from the injured knee into the healthy knee if the graft is taken from the contralateral knee. This may be an argument for favoring the semitendinosus – gracilis and the quadriceps tendons as grafts.

George Paletta, MD

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ACL RECONSTRUCTION IN THE SKELETALLY IMMATURE ATHLETE:  COMPARISON OF TWO TECHNIQUES

, Washington University, St. Louis

Purpose:  The purpose of this study was to prospectively evaluate two techniques of ACL reconstruction in the skeletally immature.  It compares reconstructing using autograft hamstring tendons via tibial and femoral bone tunnels to reconstruction via  tibial bone tunnel and over-the-top femoral approach.

Materials and Methods:  Fourteen skeletally immature adolescents (ages 10-13; 3 females, 11 males) were enrolled.  Inclusion criteria included premenarchal females, and Tanner stage 1,2, or 3 males with skeletal age <13 in females and <14 in males.  All patients had functional instability with sports activities and had failed activity modification and/or bracing.  Preoperative evaluation included physical exam, KT-1000, radiographs including full length standing AP view, scanogram, and MRI scan.  Group 1 (6/14 underwent reconstruction using a transtibial bone tunnel and over-the-top passage on the femur.  Group II (8/14) utilized transtibial and transfemoral bone tunnels.  Postoperative evaluation included serial physical exam, clinical leg length measurements, KT-1000, and serial radiographic determination of leg length.  Lysholm knee score was used pre and postoperatively.  Minimum follow-up was 2 years (range 24-40 months).  Female patients were followed for at least one year after onset of menarch.  Male patients were followed for a minimum of 2 years but at least until skeletal age of l5 years or Tanner Stage 4. 

Results: There were no significant leg length discrepancies (<1cm) or angular deformities (>5° difference).  Mean postoperative Lysholm knee score was 88 (Group 1) versus 96 (Group II).  Mean Kt 1000 difference was 3.75 mm versus 1.5 mm.  4/6 in Group I had a pivot shift versus 1/8 in Group II.  One patient in Group I complained of persistent functional instability.  All but one patient were satisfied with results and all but one patient in each group returned to the same level of preoperative sports participation. 

Conclusion:  This study demonstrates that ACL reconstructions in the skeletally immature using hamstring tendon autograft via tibial and femoral bone tunnels or tibial tunnel and over-the-top femoral approach are safe and do not result in significant leg length discrepancy or angular deformity.  Although both techniques yielded similar good subjective results and level of return to sports activity, reconstruction via tibial and femoral bone tunnels offers improved objective measurements of stability.

Name of Presenter : Hermann Mayr, M.D.

TITLE: Association of HLA with primary arthrofibrosis after ACL reconstruction

 AUTHORS: Mayr HO, Weig TG, Muench EO, Plitz W,  Skutek M, Elsner H-A, Slateva K, Blasczyk R,
                     van Griensven M, Bosch U

   Hypothesis - What is the question?

Primary arthrofibrosis represents a severe complication of ACL reconstruction due to generalized connective tissue proliferation and consecutively painful joint stiffness. It appears comprising excessive deposition of extracellular matrix proteins such as collagen type I, III and VI and proliferation of fibroblasts. However, trauma and surgery around joints do not always lead to fibrosis suggesting a genetic predisposition. For a number of autoimmune diseases strong associations have been described. The objective of the study was to investigate, whether there is an association of HLA (human leukocyte antigen) with primary arthrofibrosis

·         Method – How was the question investigated?

Out of 156 Patients with primary arthrofibrosis after ACL reconstruction 20 patients were selected at random.

DNA samples of them were typed for the loci HLA-A, -B, -Cw, -DRB1, and -DQB1. We had to exclude one patient because he belonged to another Caucasian type. The results were compared with the frequencies of allelic groups as determined for Caucasoid German population.

Statistical tests were carried out at the phenotype level using Fisher’s exact test (Svejgaard).

We saw significance with  p£0,05.

·         Results – What were the results?

-Data       

 8 ( 42,1%) patients of the arthrofibrosis group, but only 19.0% of the control group were carrier of the                                                                                                                                                                                                                                                                                                                                   

                Cw*03 criterion.

               -Statistical analysis

In the arthrofibrosis group the portion of Cw*03 positive individuals was significantly higher (p=0,034) than in the control group.

Not any other significant HLA-association was seen.

·         Conclusions

According to the relatively small number of patients a statistical bias cannot be excluded. In conclusion, a general preoperative HLA-screening does not seem to be beneficial. In some cases however, HLA-typing may be of predictive value, influencing the decision of operative vs. nonoperative treatment.

Name of Presenter: Thomas W. Patt, MD

Outcome criterias after acl-replacement – does the patient benefit from acl-replacement?

, Friederich NF, Burkart P

The Hypothesis - What is the question?

The purpose of this study was to find out possible outcome criterias in the chronic acl

unstable knee regarding evidence based medicine.

Method – How was the question investigated?

Between 1990 and 1994 87 patients with chronic anterior cruciate ligament

deficiency were operated by arthroscopic means using the central third bone-patellar

bone as transplant and could be reached for follow-up. All patients were operated on

by one surgeon. The follow up was at an average of 92 months and was done by an

independent examiner. Evaluation included a thorough patient satisfaction evaluation

(VAS), and clinical examination (KT-1000, OAK-evaluation, IKDC score, Tegner

score, Innsbruck knee sports rating scale).

Results – What were the results?

The patients were very satisfied with average 92 points on the visual analog scale.

The OAK score gave in 3.4% a satisfactory result, 10.3% of the patients scored good

and 86.3% very good results (mean 95 points). The overall IKDC showed with 16.1%

A, 71.3% B and 12.6% C also good results. Preoperative Tegner score 6.67,

postoperative 6.21. 20 patients (23%) decreased their level of activity, 67 (77%)

patients reached the same level as prior to surgery. "Innsbruck": preoperatively 13

patients scored in group 1 (high pivoting sports), 73 patients in group 2 and 1 patient

performed only non-pivoting sports before the operation. At the time of surgery all,

but 2 patients (98%) demonstrated a decrease in their sportslevel. 74 (85%) patients

improved after the surgery and 10 patients (11.5%) were still able to practice on the

level they were able to at surgery. Only 3 (3.5%) patients decreased after the

surgery– due to non-knee-related reasons.

Conclusions

Even though, the objective results were good, the question, whether the surgery

improved the patient’s quality of life is not easy to answer. Outcome criterias are

difficult to find, but eturn to pivoting sporting activities, as tested with the Innsbruck

knee sports rating scale, as well as the ability to function in daily life without any

restrictions are important criterias for the patient.

Russell F. Warren, MD

Double-Bundle PCL Reconstruction

David A. Doward, MD; ; Scott A. Rodeo, MD; Thomas L. Wickiewicz, MD; Riley J. Williams, MD;

We would like to report on our use of a two-bundle femoral insertion site for posterior cruciate ligament (PCL) reconstruction.  This procedure closely replicates the two-bundle anatomy of the PCL with the hopes of improving static stability.  Nineteen patients with PCL-deficient knees treated with this technique at our institution have been studied; 13 of them are men and 6 are women. The mean age at time of surgery was 30.1 years (range, 20 to 45 years).  Fifteen patients complained of pain and/or discomfort, 4 of swelling, and 17 of instability.  Eleven patients were involved in a sports injury (rugby, football, softball, gymnastics, snowboarding, or soccer), and 4 in a motor-vehicle accident.  Preoperatively, 8 had a grade B posterior drawer, and 11 had a grade C posterior drawer.  Four patients had an isolated PCL injury and 15 had a combined injury (ACL, MCL, LCL, PL corner, meniscus, and/or tibial plateau).  Sixteen patients received a PCL reconstruction with posterior tibial inlay; the other 3 received a tibial tunnel.  Three of these surgeries were acute reconstructions and 16 were chronic; these included a total of 6 revisions.  The mean postoperative follow-up duration was 1.3 years (range, 2 months to 4.2 years). Objective scores improved in all patients: 11 patients received a negative posterior drawer and 8 received a grade A posterior drawer with minimal offset.  All patients had significant improvement in terms of objective and subjective evaluation.  These are the best objective results for PCL reconstruction we have noted to date.  Despite the short-term nature of this study, it appears that a double-bundle approach has significantly improved the objective findings.

  Roland M. Biedert Klaus Herbert #, Christian Kurz

Revascularization following acl reconstruction: evaluation with mri in the oblique axial view

    * Institute of Sport Sciences, Orthopaedics and Sports Traumatology, CH-2532 Magglingen, Switzerland

# Department of Radiology, Clinic Linde, CH-2500 Biel, Switzerland

Purpose:  The objective of this study was to evaluate the real intrinsic revascularization of the ACL graft and to differentiate it from the increased signal intensity in the periligamentous soft tissues.  

Methods:  In the first part of the study, MR scans were taken in the coronal oblique plane in thirty patients after administration of gadolinium-DTPA (0.1 mmol/kg body weight) during a period between 1 to 4 minutes 3, 6 and 12 months after arthroscopic ACL reconstruction using B-PT-B (n=26) or QT-B (n=4). Enhancement was measured at a standardized centered region of interest in the ACL graft and as a quality control in the PCL and the cancellous bone of the proximal tibia. In the second part, oblique axial views of the same ACL grafts were obtained in 15 patients 2 to 6 months later following the suggestions of ACL Study Group members. The individual signal intensity served as a marker of the blood supply of the periligamentous soft tissues and in the graft itself.

  Results:  Increased signal intensities caused by synovialization were found in the periligamentous soft tissues of all examined patients in both planes. But we also found in 8 patients unequivocal enhancement in the center of the graft itself in the oblique axial views. Diffusion from the periphery into the graft was noted in the remaining patients. Clinical assessment revealed correct stability and function.

  Discussion:  The question if intrinsic revascularization of the ACL graft itself appears is a matter of controversy. Some authors believe that the grafts go only through a period of hypervascularization when they are impinged. We found enhancement in the center of the graft where impingement is not possible for anatomic reasons (superolateral quadrant of the notch). Longitudinal enhancement caused by the infiltrating synovium between the graft bundles (as described using double-looped hamstrings autografts) can not explain our presented higher signal intensities as we used only B-PT-B and QT-B grafts. We also documented enhancement in the center of the graft within the tibial tunnel beside the surrounding fibrous tissue.  

Conclusions:  We believe that intrinsic revascularization of the ACL graft itself can appear using B-PT-B or QT-B grafts. The origin of revascularization could be the bone-ligament junction. This would explain the discrepancies between our grafts and the hypovascular hamstrings autografts. Synovial diffusion increases the longitudinal enhancement at the same time.

William G. Rodkey, DVM

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COLLAGEN MENISCUS IMPLANTS (CMI): MULTICENTER CLINICAL TRIALS UPDATE

Purpose:  A collagen based material, the Collagen Meniscus Implant (CMI), was developed as a regeneration scaffold for meniscus cartilage and was tested in international multicenter clinical trials.  The initial purpose was to assure safety, implantability, and ability of the CMI to support new tissue ingrowth, then to establish clinical efficacy.

Methods:  The CMI is made of purified type I collagen fibers from bovine Achilles tendons.  Proteoglycans, including hyaluronic acid and chondroitin sulfate are added, and the material is aldehyde cross-linked and terminally sterilized with gamma irradiation.  The positive results of a Phase II feasibility study led to FDA approval of a large multicenter randomized (CMI versus meniscectomy alone) clinical trial of 288 patients in the United States.  These 288 patients were enrolled at 14 sites throughout the US.  Additionally, about 100 non-randomized patients were enrolled at 10 sites in Europe and two sites in Japan.  Current indications for use of the CMI include partial medial meniscus loss with intact rim and no Grade IV chondral defects.  Patients in the US multicenter trial underwent frequent clinical exams and relook arthroscopy with biopsy at one year post-implantation.

Results:  No serious or life-threatening complications have been attributed to the CMI.  Patients routinely returned to daily activities by 3 months and most were fully active by 6 months, then continued to improve through at least two years as evidenced by Tegner and Lysholm scores.  ELISA testing failed to detect any increase in antibodies to the collagen material.  No increased degenerative joint disease was observed, nor was there radiographic evidence of further joint space narrowing.  Sequential MRI examinations revealed progressive signal intensity changes indicating ongoing tissue ingrowth, regeneration, and maturation of the new tissue.  At relook arthroscopy, gross appearance and shape of the regenerated tissue generally were similar to native meniscus cartilage with solid interface to the host meniscus rim in the majority of patients.  Histologically, the collagen implant was progressively invaded and replaced by cells similar to meniscofibrochondrocytes with production of new matrix.  No inflammatory cells or histologic evidence of immunologic or allergic reactions were observed.  Approximately 100 patients in the US multicenter trial have now undergone one year relook and biopsy.

Conclusion:  The Collagen Meniscus Implant is implantable, biocompatible, and bioresorbable.  It supports new tissue regeneration as it is resorbed, and the new tissue appears to function similar to normal meniscus tissue.  Based on the relook procedures, the chondral surfaces are protected by the CMI-regenerated tissue.  No serious or life-threatening complications directly related to the CMI have thus far been reported in the multicenter trial patients, and most patients are functioning well based on clinical examination and outcomes assessment.  Relook arthroscopy results are positive and encouraging.  Similar positive European observations resulted in obtaining the EU CE mark in 2000.  Regulatory approvals are currently pending in Japan and Australia.  We anticipate that regulatory approval in the US could occur in 2004.

 Marc R. Safran, MD  

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DOES “OVERTIGHTENING” AN ANATOMICALLY PLACED ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION GRAFT

Department of Orthopaedic Surgery, University of California, San Francisco

Seventy three patients who underwent ACL reconstructions for isolated, unilateral ACL tears were prospectively followed for at least two years (average 40 months).  The endoscopic anterior cruciate ligament reconstructions were performed by one surgeon using consistent technique with patellar tendon graft and interference screw fixation.  Those patients with a postoperative (under anesthesia) KT-1000 manual maximum side to side difference under anesthesia of less than zero (“tight group”) were compared with those whose difference that was equal to or looser than the non-operative extremity (“not tight group”.)  At final follow up, the KT-1000 difference in the tight group knees was 2.1 mm, while in the not tight group, the average difference was 1.8 mm.  An anatomically placed central third patellar tendon graft with interference fixation that is tighter than the normal, contralateral knee loosens more than an ACL graft that is equal to or looser than the normal knee.  However, the ultimate side-to-side difference was similar and there was no greater failure rate in the knees made tighter.  Thus ACL graft over-tightening does not appear to affect clinical results. 

BUCKETHANDLE MEDIAL MENISCUS TEARS IN ACL RECONSTRUCTED KNEE: LONG TERM OUTCOME

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K. DONALD SHELBOURNE, MD and DONALD R. CARR, MD, LCDR MC USN

Objective:  For patients who underwent ACL reconstruction and had an unstable bucket handle medial meniscus tear but no other meniscus lesion or articular cartilage damage, we sought to determine the level of superiority meniscus repair had above partial meniscectomy with regard to subjective and objective outcomes.

Methods:  Between 1982 and 1995, 155 patients met the inclusion criteria.  All patients underwent ACL reconstruction using patellar tendon autografts.  Fifty-six patients underwent medial meniscus repair using inside-out technique.  In 99 patients, the medial tear was felt to be non-salvageable and a partial medial meniscectomy was performed. Subjective follow-up was obtained with a modified Noyes knee questionnaire.  Patients were objectively evaluated using the IKDC knee examination criteria.

Results: The mean subjective score of 51 patients in the repair group was 90.9 ± 11.6 points at a mean of 8.9 years after surgery; the mean for 87 patients in the meniscectomy group was 90.9 ± 16.7 points at a mean of 7.8 years after surgery (P=0.634).  IKDC overall grades on 25 patients in the repair group (mean time 7.1 years) were normal in 13 (52%), nearly normal in 9 (36%), and abnormal in 3 (12%).  IKDC overall grades on 56 patients in the removal group (mean time, 6.0 years) were normal in 26 (46%), nearly normal in 25 (45%), and abnormal in 5 (9%).  IKDC radiographic sub-scores for the repair group were normal in 20, nearly normal in 3 and abnormal in 1; the radiographic sub-scores for the removal group were normal in 41, nearly normal in 8 and abnormal in 3.  The distributions in grades were not statistically significantly different between groups (P=0.7467, overall grade; P=0.8977, radiographs).  Fourteen of the 15 radiographs graded as nearly normal or abnormal were obtained at > 5 year follow-up.

Conclusions: In patients with ACL reconstructed knees with unstable and isolated bucket handle medial meniscus tears, the data at 7 years follow-up did not demonstrate superior subjective and objective outcomes with meniscus repair versus partial removal.  These results reinforce the need to obtain long-term follow-up on all meniscus procedures before success or failure of treatment can be determined.  IN addition, we need to critically analyze the risks, benefits, and criteria for meniscus repair in patients undergoing ACL reconstruction with unstable bucket handle meniscus tears.

J. Richard Steadman MD,

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Lysis of Pretibial Patellar Tendon Adhesions (“Anterior Interval Release”) to Treat Anterior Knee Pain After ACL Reconstruction

 Sumant Krishnan MD,

Anterior knee pain (AKP) after arthroscopic ACL reconstruction has been a well-documented complication.  AKP has been attributed to “infrapatellar contracture syndrome” or to patellar tendon adhesions to the anterior tibia that restrict patellar mobility.   We report our results of “anterior interval release” for treatment of recalcitrant AKP associated with decreased patellar mobility after ACL reconstruction. 

Methods:  Between 1995 and 1998, 19 consecutive patients with recalcitrant AKP and decreased patellar mobility after ACL reconstruction underwent arthroscopic “anterior interval release”.  Initial ACL procedures were autograft BTB reconstructions.  All patients participated in the same structured postoperative rehabilitation program emphasizing early restoration of motion.  AKP was treated with patellar mobilization exercises and NSAID’s.  Failure of nonoperative treatment was defined as no improvement in functional outcome, as assessed by Lysholm scores and patient subjective questionnaire. Statistical significance for data analysis was p<0.05.

Results:  After failure of nonoperative treatment, preoperative Lysholm score average was 68 (range 18-90).  Postoperative Lysholm score averaged 85 (range 68-100)(p<0.0001).  Flexion and extension did not change significantly from pre to postoperatively.  Preoperative and postoperative Lachman, posterior drawer, varus and valgus examination were graded 0 in all patients.  No patient demonstrated posterolateral instability.    Preoperatively, 74% of patients reported moderate to severe pain, 63% reported moderate to severe stiffness, and   58 % reported their knee functioned abnormally.  Postoperatively   21% patients reported moderate to severe pain, 5% reported moderate to severe stiffness, and 16% reported their knee functioned abnormally.   Average patient satisfaction at follow-up was 8.0 (1=very dissatisfied; 10 =very satisfied).

Conclusion:  Pretibial patellar tendon adhesions after ACL reconstruction can be a debilitating source of AKP and poor functional results.  Consequently, we have altered our postoperative ACL rehabilitation program to include an aggressive emphasis on patellar and patellar tendon mobilization exercises. Early operative intervention “anterior interval release” has been shown in this series to result in significantly improved functional outcomes when patients develop marked AKP after ACL surgery. 

TP Branch,

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Treatment of Grade II Medial Meniscal Tears  with Persistent Joint Line Pain

 TJ Mills

Dekalb Medical Center, Decatur, Georgia 30033 

There exists a group of medial meniscal tears categorized by our friends the radiologists as Grade II based upon their reading of an MRI scan.  These patients present with symptoms of medial joint line pain and have a physical examination consistent with a medial meniscal injury.  When the radiologist reviews the MRI it is read as a Grade II tear.  That is to say there is a signal within the meniscus but the abnormal signal does not extend to the surface indicating a frank tear.  Despite a convincing history and physical examination these patients are told that they are not candidates for surgery.  Occasionally they are arthroscoped secondary to persistent pain but a menisectomy is not performed due to the lack of visual pathology.  At previous ACL Study Group meetings Dr. Roland Beidert presented several studies discussing the treatment of these lesions.  He suggested that a partial medial menisectomy had the best long-term outcome. 

Blood contains cytokines and growth factors, which aid in the healing of damaged soft tissues.  We hypothesized that if the Grade II meniscal tear identified by MRI scan was the cause of persistent joint line pain in a group of patients, then an intrameniscal injection of the patient’s blood would promote the healing of the tear and a reduction in the patient’s symptoms.

Methods:  This is a retrospective chart review of 15 patients with persistent medial joint line pain and a documented Grade II medial meniscal tear by MRI scan.  These Grade II tears were isolated lesions with no other joint pathology noted.  There were 6 men and 9 women with an average age of 34 (range 15 – 58).  There were 7 left and 8 right knees.  All patients received physical therapy for an average of 7 months prior to surgery with a range from 3 months to 2 years.  Six of the fifteen patients underwent an awake diagnostic arthroscopy under local anesthesia to confirm the location of their pain. Follow-up was by phone or patient interview at an average of 3 years and 9 months.  All patients had a six weeks post-operative physical therapy program.

Results:  All fifteen patients had complete relief of their medial joint line pain.  One patient had persistent anterior knee pain.  No patient experienced the same symptoms that pushed him or her to come to the orthopedist

Conclusion:  Grade II medial meniscal tears documented by MRI scan in patients with symptoms and physical findings consistent with a medial meniscal tear do indeed have a significant injury.  Treatment of these lesions with intrameniscal blood injection shows promising results by the elimination of symptoms over a prolonged period.  Standard arthroscopy with the patient asleep may not identify these lesions.  Awake arthroscopy with portal anesthesia only is helpful in confirming the diagnosis.

Name of Presenter: Thomas D. Rosenberg, M.D.