John A. Bergfeld

Long-term results of nonoperative treatment of isolated posterior cruciate ligament injuries in the athlete

The long-term results of 25 patients treated nonopera tively with isolated posterior cruciate ligament (PCL) injuries were evaluated. Mean followup was 6.2 years (range, 2.2 to 16 years). All patients were evaluated both subjectively (questionnaire) and objectively (clinical examination, x-ray films, Cybex II dynamometer, and KT-1000 Knee Arthrometer). At followup, 80% of the patients were satisfied with their knees and 84% had returned to their previous sport (68% at the same level of performance, 16% at a decreased level of performance). Mean torque Cybex II quadriceps values for three velocities of testing (45, 90, and 180 deg/sec) in patients fully returned to sport and satisfied with their knees was greater than 100% of uninvolved quadricep; conversely, those not satisfied with their knees all had values less than 100% of uninvolved knee. The amount of knee instability as determined by the KT-1000 Arthrometer was not re lated to the patients return to sport nor to knee satis faction. We concluded that the majority of athletes with isolated PCL injuries who maintain strength in muscu lature return to sports without functional disability.

The Effect of Allograft Meniscal Replacement on Intraarticular Contact Area and Pressures in the Human Knee A Biomechanical Study

To define the biomechanical effects of total lateral meniscectomy and of subsequent lateral meniscal al lograft replacement on load transmission and distribu tion across the human knee, we mounted 10 fresh- frozen, young human cadaveric knees on a mechanical testing system. Peak pressure and contact area profiles were determined at 0°, 30°, and 60° of knee flexion using pressure-sensitive film and a den sitometer. Load transmission profiles were determined for each knee in a sequential test order: 1)intact knee, 2) after lateral meniscectomy, 3) after implantation of size-matched meniscal allograft fixed with bone plugs, and 4) after release of the anterior and posterior horn attachments of the allograft. Total lateral meniscec tomy resulted in a 45% to 50% decrease in total con tact area. Allograft replacement increased total contact area by 42% to 65% as compared with total meniscec tomy at all flexion angles. After release of the anterior and posterior horn attachments, contact area was identical to that after total meniscectomy. Total lateral meniscectomy resulted in a 235% to 335% increase in peak local contact pressure. Allograft replacement de creased these pressures by 55% to 65% at all flexion angles, but they remained significantly greater than those in the intact state. After release of the anterior and posterior horn attachments, contact pressures were identical to those after total meniscectomy. Com pared with total meniscectomy, meniscal allograft transplantation significantly increases contact area and decreases peak local contact pressures, but any bio mechanical advantages are lost without bone plug fix ation of the anterior and posterior horns.

Prospective study of osseous, articular, and meniscal lesions in recent anterior cruciate ligament tears by magnetic resonance imaging and arthroscopy

Fifty-four patients with anterior cruciate ligament tears that were arthroscopically reconstructed within 3 months of initial injury were prospectively evaluated. Patients with grade 3 medial collateral ligament, lateral collateral ligament, or posterior cruciate ligament tears were excluded. Eighty percent of our patients had a bone bruise present on the magnetic resonance image, with 68% in the lateral femoral condyle. Two of the latter findings—an abnormal articular cartilage signal (P = 0.02) and a thin and impacted subchondral bone (P = 0.03)—had a significant relationship with injury to the overlying articular cartilage. Meniscal tears were found in 56% of the lateral menisci and 37% of the medial menisci. A significant association was present between bone bruising on the lateral femoral condyle and the lateral tibial plateau (P = 0.02). Results of our study support the concept that the common mechanism of injury to the anterior cruciate ligament involves severe anterior subluxation with im paction of the posterior tibia on the anterior femur. Determination of the significance of bone bruising, ar ticular cartilage injury, or meniscal tears will require a long-term followup that includes evaluation for arthritis, stability, and function. These 54 patients represent the first cohort evaluated in this ongoing prospective clinical study.

A biomechanical comparison of posterior cruciate ligament reconstruction techniques.

Most posterior cruciate ligament reconstruction techniques use both tibial and femoral bone tunnels for graft placement. Because of the acute angle the graft must make to gain entrance into the tibial tunnel, abnormal stresses are placed on the graft that could lead to graft failure. An alternative technique for posterior cruciate ligament reconstruction involves placement of the bone plug from the graft anatomically on the back of the tibia (inlay), preventing formation of an acute angle at the tibial attachment site. We used six pairs of human cadaver knees to compare the biomechanical properties of these two techniques. One knee from each pair underwent tunnel reconstruction while the other knee underwent inlay reconstruction. There was significantly less anterior-posterior laxity in the inlay group when compared with the tunnel group from 30° to 90° of knee flexion and after repetitive loading at 90° of knee flexion. Evaluation of the grafts revealed evidence of mechanical degradation in the tunnel group but not in the inlay group. The inlay technique resulted in less posterior translation with less graft degradation than did the tunnel technique for posterior cruciate ligament reconstruction.

Risk of Tearing the Intact Anterior Cruciate Ligament in the Contralateral Knee and Rupturing the Anterior Cruciate Ligament Graft During the First 2 Years After Anterior Cruciate Ligament Reconstruction A Prospective MOON Cohort Study

Background The risk of tear of the intact anterior cruciate ligament in the contralateral knee after anterior cruciate ligament reconstruction of the opposite knee and the incidence of rupturing the anterior cruciate ligament graft during the first 2 years after surgery have not been extensively studied in a prospective manner. Clinicians have hypothesized that the opposite normal knee is at equal or increased risk compared with the risk of anterior cruciate ligament graft rupture in the operated knee. Hypothesis The risk of anterior cruciate ligament graft rupture and contralateral normal knee anterior cruciate ligament rupture at 2-year follow-up is equal. Study Design Cohort study; Level of evidence, 2. Methods The Multicenter Orthopaedic Outcome Network (MOON) database of a prospective longitudinal cohort of anterior cruciate ligament reconstructions was used to determine the number of anterior cruciate ligament graft ruptures and tears of the intact anterior cruciate ligament in the contralateral knee at 2-year follow-up. Two-year follow-up consisted of a phone interview and review of operative reports. Results Two-year data were obtained for 235 of 273 patients (86%). There were 14 ligament disruptions. Of these, 7 were tears of the intact anterior cruciate ligament in the contralateral knee (3.0%) and 7 were anterior cruciate ligament graft failures (3.0%). Conclusion The contralateral normal knee anterior cruciate ligament is at a similar risk of anterior cruciate ligament tear (3.0%) as the anterior cruciate ligament graft after primary anterior cruciate ligament reconstruction (3.0%).

Posterior shoulder instability Surgical versus conservative results with evaluation of glenoid version

We conducted a retrospective study on 50 patients with recurrent posterior shoulder instability. Twenty- five patients were treated conservatively with a specific rehabilitation program strengthening the rotator cuff. The other 25 patients, who did not improve with reha bilitation, underwent surgical reconstruction, the major ity of these being soft tissue repairs. Recurrence in the surgically treated group averaged 72% while that in the conservatively treated group was 96%. However, 50% of those patients treated surgically and 68% of those treated conservatively felt their symptoms were im proved. In view of the high recurrence rate with soft tissue reconstruction, computed tomography scans were ob tained to evaluate glenoid version. Those patients with posterior shoulder instability were found to have in creased glenoid retroversion when compared to an uninjured population (P < 0.05). Our conclusions based on this study were that 1) specific therapy in the form of rotator cuff strengthening should be the initial form of treatment in patients with posterior shoulder insta bility, 2) soft tissue surgery has a high rate of recur rence, 3) the return to sports is variable, 4) there appears to be an increased incidence of glenoid retro version in this patient population, and 5) the incidence of posttraumatic arthritis is low.

A Biomechanical comparison of posterior cruciate ligament reconstructions using single- and double-bundle tibial inlay techniques

Background The efficacy of using a double-bundle versus single-bundle graft for posterior cruciate ligament reconstruction has not been demonstrated. Hypothesis A double-bundle graft restores knee kinematics better than a single-bundle graft does in tibial inlay PCL reconstructions. Study Design Controlled laboratory study. Methods Eight cadaveric knees were subjected to 6 cycles from a 40-N anterior reference point to a 100-N posterior translational force at 10°, 30°, 60°, and 90° of flexion. Testing was performed for the intact and posterior cruciate deficient knee as well as for both reconstructed conditions. Achilles tendons, divided into 2 equal sections, were prepared as both single-bundle and double-bundle grafts. Both grafts were employed in the same knee, and the order of graft reconstruction was randomized. Results There were no statistical differences in translation between the intact state and either of the reconstructions (P >. 05) or between either of the reconstructions at any flexion angle (P >. 05). Conclusion No differences in translation between the 2 graft options were identified. Clinical Relevance The use of a double-bundle graft may not offer any advantages over a single-bundle graft for tibial inlay posterior cruciate reconstructions.

A Prospective Study on the Management of Shin Splints

A study of 2,777 first-year midshipmen was done using four prophylactic programs for prevention of shin splints. None were effective. Treatment of the ninety-seven men in whom shin splints developed was divided into five regimens. All were effective to varying degrees. Prohibition of running was common to all the treatments.

Menstrual Abnormalities, Nutritional Patterns, and Body Composition in Female Classical Ballet Dancers

In brief: Classical ballet is a demanding discipline that until recently has been largely ignored by the medical and exercise communities. The authors studied the nutritional habits of 34 high-level classical ballet dancers during three days of a typical rehearsal week and found that they consumed only 71.6% of the recommended daily allowance for nutrients. Their average percent body fat was 16.9%. Many (17) had menstrual abnormalities, 15 had secondary amenorrhea, and 11 cited irregularities they felt were directly due to dancing. No statistical correlation could be found between the reported menstrual abnormalities and percent body fat or the age they began training.

Intramuscular Corticosteroid Injection for Hamstring Injuries A 13-Year Experience in the National Football League

The purpose of this study was to assess the safety of intramuscular corticosteroid injection in selected, severe hamstring injuries in professional football players. Clinicians have been reluctant to use corticosteroid injections in or around muscle-tendon units because of concern of incomplete healing or rupture. We retrospectively reviewed the computer database of one National Football League team for all hamstring injuries requiring treatment between January 1985 and January 1998. We found that 431 players had suffered such injury. We developed a clinical grading system to identify hamstring injury severity and to stratify players for treatment. Fifty-eight players (13%) sustained severe, discrete injuries with a palpable defect within the substance of the muscle and were treated with intramuscular injection of corticosteroid and anesthetic. There were no complications related to the injection of corticosteroid. Only nine players (16%) missed any games as a result of their injury. Final examination revealed no strength deficits, normal muscle bulk and tone, and the ability to generate normal power. We believe that the grading system we developed can assist in selection of injury type for injection. Although lack of a control group limits statements of efficacy of injection, our impression is that intramuscular corticosteroid injection hastens players’ return to full play and lessens the game and practice time they miss.