The American Journal of Sports Medicine

We assessed short-term treatment results of younger patients with varus malalignment and chronic anterior cruciate ligament deficiency. Forty-one patients (mean, 32 years; range, 16 to 47) underwent a high tibial osteotomy. Because of giving way symptoms, 14 also had a lateral iliotibial band extraarticular procedure at the time of the osteotomy and 16 had an intraarticular anterior cruciate ligament allograft reconstruction after the osteotomy. All returned for followup (mean, 58 months; range, 23 to 86), which included KT-1000 arthrometer testing and evaluation by our knee rating system.

Statistically significant (P < 0.05) improvements were found in the mean overall rating scores for pain, swell ing, and giving way. Preoperatively, 30 (73%) had pain with activities of daily living or with any sports activity; 11 (27%) could perform only light sports activities with out pain. At followup, 32 patients (78%) had no pain with activities of daily living or light sports.

Ten of 15 patients with advanced medial tibiofemoral arthrosis (subchondral bone exposure) had significant improvements in symptoms.

Patient satisfaction was high: 88% stated they would undergo the procedure again and 78% felt their knee condition was improved.

Patients who had the allograft reconstruction had significantly lower (P < 0.05) anterior-posterior dis placements at followup than those who had the extraar ticular procedure.

We concluded that osteotomy should be performed early in the disease process for younger athletes who experience symptoms with activity. It may be unrealis tic, however, to expect continuation of sports beyond light recreational, given the joint arthrosis that is usually present and the high in vivo joint loadings with athletes. Anterior cruciate ligament reconstruction should be considered when giving way previously occurred and the patient plans to resume athletics. However, patients with advanced arthrosis can avoid anterior cruciate ligament surgery by reducing athletic activities.

We report demographic, clinical, and imaging data on 92 patients with osteochondral lesions of the talus collected in one center between 1981 and 1992. All patients reported pain as their primary symptom. Ninety-four percent of the patients reported pain with activity. Physical examination was unhelpful. Using newer imaging techniques (bone scan and computed tomography) and with increased awareness, we have observed a sevenfold increase in the diagnostic fre quency of osteochondral lesions of the talus between the years 1981 to 1986 and 1987 to 1992. Bone scan is an excellent screening tool for patients with chronic ankle pain and has 99% sensitivity in depicting osteo chondral lesions.¹⁶ Computed tomography demon strated a previously unclassified lesion, the radiolucent defect, which accounts for 77% of the lesions in this series. We have therefore modified the Berndt and Harty classification system, basing it on radiographic appearance (principally computed tomography) and adding the radiolucent lesion.

Fifty-eight patients were treated surgically. Anterior and midtalar lesions are now approached arthroscopi cally. Surgical treatment of the radiolucent lesion, con sisting of curettage and drilling, gives 42% excellent and 32% good results. Pain relief often occurs within months of surgery, but healing of the lesion requires years, and some may persist indefinitely.

Twenty consecutive patients with combined anterior cruciate/medial collateral ligament injuries were ana lyzed to determine if a correlation exists between the location of medial collateral ligament disruption and postoperative return of motion. All patients were treated operatively by autogenous patellar tendon an terior cruciate ligament reconstruction and primary me dial collateral ligament repair. The mean followup was 379 days.

The patients (12 men and 8 women; mean age, 23 years) were divided into two groups based on the location of superficial medial collateral ligament rupture. Group P consisted of 13 patients with lesions at or proximal to the joint line; Group D consisted of 7 patients with disruptions distal to the joint line.

Group D patients had a more rapid return of motion for both flexion and extension. At the conclusion of followup, patients from Group D also achieved 8° more flexion and 3° more extension. There were eight addi tional procedures performed on five patients, all from Group P, required to treat difficulty regaining motion.

Among those patients with anterior cruciate/medial collateral ligament injuries there are two distinct groups, each with different prognoses related to return of mo tion based on the location of the medial collateral liga ment disruption. We suggest that patients with double- ligament injuries, where the medial collateral ligament lesion is proximal, should be managed very aggres sively to regain motion.

To determine the ability of prophylactic knee braces to reduce or limit medial collateral and anterior cruciate ligament elongation under dynamic loading conditions, we used cadaveric specimens that had a surrogate soft tissue material that matched the tissue compliance of in vivo contracted muscles.

Eight cadaveric specimens were fitted with four pro phylactic knee braces and instrumented with Hall Effect Strain Transducers on both the medial collateral and anterior cruciate ligament. Each specimen was mounted in a testing frame while a lateral impact was applied to the knee joint by a pendulum at levels below the injury threshold. Legs were tested at 0° and 30° of knee flexion, both with and without an intact anterior cruciate ligament.

The maximum elongation for each ligament was cal culated as a percentage of the initial measured length. The addition of a prophylactic knee brace significantly reduced the level of impact force at the point of impact, but this did not result in a significant reduction of anterior cruciate ligament elongation for any test. Al though not significant, all braces tested were more effective at reducing medial collateral ligament elonga tion during a lateral impact with the knee flexion at 30° than at 0°.

Anterior compartment pressure was measured in 10 competitive runners and in 10 competitive cyclists who were asymptomatic for compartment syndrome. Pres sures were measured at rest, after exercise at 80% VO₂max, after maximal exercise, and 15 minutes after both exercise bouts. No difference in compartment pressure was found after exercise at 80% VO₂max in runners and cyclists. Total creatine phosphokinase en zyme levels measured before and after exercise at 80% VO₂max showed a 1 0-fold increase in runners as com pared to cyclists. Anterior compartment pressure meas ured after maximal exercise was significantly greater in runners as compared to cyclists. Compartment pres sure showed no increase from resting values during cycling at 80% VO₂max or maximal exercise. These findings suggest that patients with chronic anterior compartment syndrome may be able to cycle without elevation of compartment pressure and concomitant pain as an alternative exercise to maintain a continued degree of fitness and training. Compartment pressures should be measured during cycling in patients with chronic compartment syndrome to determine its effi cacy as a method for maintenance of cardiorespiratory fitness.

This study compared water running, cycling, and run ning for maintaining VO₂max and 2-mile run perform ance over a 6-week training period. Thirty-two trained subjects between the ages of 18 and 26 were evaluated for maximum oxygen uptake (VO₂max) and 2-mile run performance. Subjects were stratified by a 2-mile run pretest into high, medium, and low performance levels and then randomly assigned to water running, cycling, or running training. The three groups trained with similar frequency, duration, and intensity over a 6-week period. After 6 weeks of training, all of the groups made a small but statistically significant decrease in fitness (VO₂max), but no change in 2-mile run time. However, there were no differences with respect to either training modality or pretraining performance level. It was concluded that over a 6-week period, runners who cannot run because of soft tissue injury can maintain VO₂max and 2-mile run performance similar to running training with either cycling or water running.

Aqua running has been promoted as a method for cardiovascular conditioning for the injured athlete as well as for others who desire a low impact aerobic workout. Recent studies have suggested the need for an environment-specific measure of exercise intensity. Twenty healthy subjects, 10 men and 10 women, underwent a graded exercise test of aqua running to investigate the relationship between cadence and heart rate. This was done to determine the utility of cadence as a measure for exercise prescription. The graded exercise test followed a standard protocol for exercise testing in aqua running. Results demonstrated a high correlation between cadence and heart rate, both as a group as well as individually. We conclude that cadence may be used as a measure for exercise prescription for aqua running.

The purpose of this study was to quantify the amount of anterior tibial displacement occurring in anterior cru ciate ligament-deficient knees during two types of re habilitation exercises: 1) resisted knee extension, an open kinetic chain exercise; and 2) the parallel squat, a closed kinetic chain exercise. An electrogoniometer system was applied to the anterior cruciate ligament- deficient knee of 11 volunteers and to the uninvolved normal knee in 9 of these volunteers. Anterior tibial displacement and the knee flexion angle were meas ured during each exercise using matched quadriceps loads and during the Lachman test. The anterior cru ciate ligament-deficient knee had significantly greater anterior tibial displacement during extension from 64° to 10° in the knee extension exercise as compared to the parallel squat exercise. In addition, the amount of displacement during the Lachman test was significantly less than in the knee extension exercise, but signifi cantly more than in the parallel squat exercise. No significant differences were found between measure ments in the normal knee. We concluded that the stress to the anterior cruciate ligament, as indicated by ante rior tibial displacement, is minimized by using the par allel squat, a closed kinetic chain exercise, when com pared to the relative anterior tibial displacement during knee extension exercise.

A knowledge of the patterns of injury to the compo nents of the iliotibial tract allows a clearer interpretation of motion limits testing in patients with abnormal ante rior tibial translation of the knee (anterior cruciate liga ment-deficient knees).

Eighty-two consecutive patients with acute knee in juries were classified as anteromedial-anterolateral ro tatory instability (anterior cruciate ligament-deficient) based on the abnormal motion demonstrated by clinical examination tests for instability. At surgery, injuries to the intraarticular and extraarticular anatomic structures were identified and correlated to the abnormal grades of motion demonstrated by the knee motion limits ex amination.

Tears of the anterior cruciate ligament occurred in 80 (98%) of the knees. However, the grade of abnormal motion demonstrated by the Lachman and pivot shift tests was quite variable. This variation did not correlate statistically with anterior cruciate ligament tears.

Injuries to the anatomic components of the iliotibial tract were confirmed in 76 (93%) of the knees. These injuries correlated highly with variations in grades of abnormal motion detected by the following tests: lateral joint line opening at 30° (r ² = 0.05); Lachman test (r ² = 0.08); pivot shift (r ² = 0.16); and anterior translation at 90° of flexion (r ² = 0.34). Thus, injuries to the components of the iliotibial tract are thought to contrib ute to the variation in grades of abnormal motion ob served in this complex subgroup of anterior tibial trans lation instabilities.

The purpose of this study was to establish a data base regarding the isokinetic muscular performance charac teristics of the external/internal rotator muscles of professional baseball pitchers. One hundred fifty healthy professional baseball pitchers were evaluated by use of a Biodex isokinetic dynamometer. The sub jects tested had a mean age of 23.4 years and a mean body weight of 199 pounds. Isokinetic tests were per formed concentrically at 180 and 300 deg/sec for both the throwing and nonthrowing shoulders. Testing pro cedures regarding positioning and stabilization followed established guidelines. The testing protocol and actual test repetitions were standardized for each subject. Statistical analysis was performed using the Pearson Product Moment Correlation and paired t-tests. Deter mination of the correlation coefficient was made at the P < 0.05 level of significance.

Test results for bilateral comparison of mean peak torque for the throwing and nonthrowing shoulders indicated no statistically significant difference between the internal rotators at both test speeds, or for the external rotators at 300 deg/sec. There was a signifi cant statistical difference at the 180 deg/sec test speed for the external rotators. The external/internal rotator strength ratio indicated a 65% ratio at 180 deg/sec and a 61 % ratio at 300 deg/sec. Data were also collected for mean peak torque/body weight ratios of the throw ing shoulder to establish a data base in professional throwers.

This study offers clinical relevance in establishing a muscle performance profile for the professional thrower. This data base can therefore be used as criteria that should be met before an injured pitcher can be returned to throwing at the professional baseball level.

The prevalence of shoulder pain in United States com petitive swimmers has not been extensively surveyed but is perceived as common. To evaluate this concern, a questionnaire survey was conducted on 1262 United States swimmers: 993 age group, 198 senior develop ment, and 71 national team athletes. We sought to identify the incidence of interfering shoulder pain in this population and how it is influenced by various training tasks. The prevalence of current shoulder pain in these groups varied between 10% (age group) to 26% (na tional team) and increased with time in the sport. In those athletes with a painful shoulder, weight training, use of hand paddles, kickboard use, stretching, and various resistance activities aggravated the painful shoulder. This survey has identified that interfering shoulder pain is present in a substantial number of competitive swimmers.

Arthroscopic resection of the distal clavicle was used to treat 26 patients who had osteoarthritis of the acro mioclavicular joint. Twenty of these patients were avail able for review at a minimum followup of 2 years. The preoperative ratings for pain, activities of daily living, work, and sports improved markedly in 17 patients postoperatively. No intraoperative complications were noted. The operation was unsuccessful in 3 patients and all underwent a second, open surgery. The results show that arthroscopic resection was effective in the treatment of isolated acromioclavicular joint arthritis.

The lack of agreement on definition of terms and con sistent reporting strategies in sports epidemiology com plicates the determination of injury rates in any sport. This study describes Canadian Intercollegiate ice hockey injuries over a 6-year period by following a standardized reporting strategy and clearly defined ter minology. Overall, the data show that the knee is most susceptible to injury, that the forwards recorded the highest number of injuries, and that body contact caused the majority of injuries. Compared to other studies the results indicate a decreasing per game injury rate over the last 15 years and provide evidence that helmets and visors reduce the risk of head and facial injuries. Recommendations are propagated to ward the adherence of standardized reporting strate gies and uniform definitions to be used in future sports injury epidemiologic research.

This study was designed to compare the displacement patterns of an isometer, used to determine graft place ment during reconstruction, with the actual tensions on an anterior cruciate ligament substitute. In cadaveric specimens, a Kevlar anterior cruciate ligament substi tute was implanted in three separate femoral sites, each of which was subsequently fixed to two different tibial sites. The initial tension of the Kevlar substitute was set to 22 or 33 N at 20° of knee flexion. The displacement patterns for each position were recorded during passive flexion-extension using the isometer. Using a custom-designed tensiometer, the tensile forces on the substitute after rigid fixation at the tibia and femur were measured. During passive flexion-ex tension, the maximum change in tension of the anterior cruciate ligament substitute, measured by the tensiom eter, was correlated with the maximum change in dis placement between attachment sites, measured by the isometer. The coefficient of determination was equal to 0.15, indicating that the isometer may not accurately predict the tensions developed in the substitute.

We reviewed our experience with computed tomogra phy and magnetic resonance imaging of acute muscle strain injury. We imaged 50 athletes (average age, 28 years; range, 17 to 42) who had an acute muscle strain involving either the adductor, hamstring, quadriceps, or triceps surae muscles. Computed tomography (axial imaging) was used from 1982 to 1987 for 27 athletes. Spin-echo magnetic resonance imaging (axial, coronal, sagittal imaging) was used from 1987 to 1991 for 23 athletes.

Computed tomography and magnetic resonance im aging localize the strain injury to a single muscle within a group of synergists; the adductor longus, rectus femoris, and medial head of gastrocnemius muscles are most prone to strain injury. A disruption occurs predictably at the myotendinous junction; fluid collects at the disruption site and dissects along the epimysium and subcutis. Muscle tissue remote from the myoten dinous junction clearly demonstrates extensive injury with abundant magnetic resonance imaging signal changes consistent with edema and inflammation. Fol low-up computed tomographic and magnetic reso nance imaging studies can clearly demonstrate atrophy, fibrosis, and calcium deposition.

Fifty former amateur boxers were examined and com pared with two control groups of soccer players and track and field athletes. All subjects were interviewed regarding their sports career, medical history, and so cial variables. They underwent a physical and a neuro logic examination. Personality traits were investigated and related to the platelet monoamine oxidase activity. Cerebral morphologic changes were evaluated using computed tomography and magnetic resonance imag ing. Further, clinical neurophysiologic tests were made as well as neuropsychologic tests.

No significant differences were found between the groups in any of the physical or neurologic examinations or in platelet monoamine oxidase activity. Socially, the boxers had a lower degree of education and had cho sen less intellectual professions, but they were less impulsive and more socialized. The computed tomog raphy images and magnetic resonance imaging studies showed no significant differences between the groups. There was a significantly higher incidence of slight or moderate electroencephalography deviations among the boxers. Neuropsychologically, the boxers had an inferior finger-tapping performance. Thus, no signs of serious chronic brain damage were found among any of the groups studied. However, the electroencepha lography and finger-tapping differences between the groups might indicate slight brain dysfunction in some of the amateur boxers.

A review of 250 cases of surgical reconstruction of the anterior cruciate ligament identified 24 patients with bilateral complete tears of the anterior cruciate liga ment. Twenty of these patients had previous recon struction of one anterior cruciate ligament before rup ture of the opposite ligament. Twelve injuries occurred during the same activity that was responsible for the initial opposite injury. The average time between sur gical reconstruction and rupture of the opposite liga ment was 29.3 months (range, 3 to 103). No significant demographic differences existed between patients with unilateral or bilateral ruptures of the anterior cruciate ligament.

Standardized measurements of intercondylar notch height and width and medial and lateral femoral condyle height and width were performed on routine notchview radiographs of 31 knees of patients with bilateral inju ries, 30 with unilateral injury, and 30 with no anterior cruciate ligament injury. Statistical analysis revealed no significant differences between the three groups when comparing absolute measures or any of eight mathe matical ratios calculated from these measurements. We concluded that measurements of the intercondylar notch made from radiographs may not be reliable pre dictors of injury to the anterior cruciate ligament. We found no significant clinical or demographic differences between patients with unilateral or bilateral complete ruptures of the anterior cruciate ligament.

Ten athletes with distal biceps tendon ruptures that had been anatomically repaired with a double-incision technique were reviewed to determine their functional recovery. All of the patients were men, with an average age of 40 years (range, 25 to 49). Eight of the 10 patients were weight lifters or body builders, and 7 had participated on a competitive level at some point in their athletic careers. Six injured their dominant extremity, and 4 their nondominant extremity. Isokinetic muscle testing of supination and flexion was performed in 8 patients and the results were compared to a control group. Followup averaged 50 months (range, 12 to 105).

Patients uniformly graded their subjective results as excellent, with a group mean rating of 9.75 on a 10- point scale. All athletes returned to full, unlimited activ ity. The contour of the biceps muscle was restored in all cases. Isokinetic muscle testing demonstrated that in those patients with a repaired dominant extremity, supination strength and endurance was normal; in flex ion, they had normal strength, but averaged 20% less endurance. Testing of the group that had the nondom inant extremity repaired revealed a supination strength deficit of 25%, but normal endurance. Flexion strength and endurance were essentially normal in this group.

Anatomic repair of a distal biceps tendon rupture gives consistently excellent subjective and good objec tive results in athletes, particularly for those sports with high strength demands such as weight lifting and body building. Rehabilitation of the operated arm, especially the repaired nondominant extremity, should be empha sized.

To investigate intraarticular lesions producing persist ent postoperative pain, we arthroscopically examined 31 ankles in 31 patients (15 women and 16 men) with lateral ligament injury. The patients ranged in age from 15 to 33 years, with a mean of 20 years. Nine patients were freshly injured, and 22 patients had chronic inju ries. All of the patients underwent arthroscopic exami nation immediately before the ligament operation. Chondral lesions were found in 89% of the freshly injured ankles and 95% of the ankles with chronic injuries. Most of these lesions were in the medial half of the ankle joint, especially in the anteromedial edge of the tibial plafond. After followup for 1 year postop eratively, persistent pain was noted in 4 patients who had chondral lesions of greater than one-half the thick ness of the articular cartilage. Pain and tenderness were localized at the anteromedial joint line, corre sponding to the location of the chondral lesions. Chon dral lesions of greater than one-half the thickness of the articular cartilage were found in 8 ankles in the chronic injury group, but there were none in the fresh injury group.

Thus, in lateral ligament injuries of the ankle, the longer the time elapsed from the initial injury, the more severe the associated chondral lesions became. These chondral lesions appear to cause persistent pain.

We reviewed 30 patients at an average of 7.4 years after acute repair of the anterior cruciate ligament aug mented with a loop of iliotibial tract. A noncontact twisting had been the mechanism of injury in 18 of these patients, with 28 having been injured in sports. At followup, 25 patients had not experienced symptoms of instability and 23 were able to return to unrestricted athletic activity; only 5 had been unable or unwilling to return to sporting activity at all. There had been no swelling in 23 patients; however, 17 suffered from pain on exertion. The average Lysholm score was 93.2.

Joint laxity was assessed and anteroposterior tibial translation quantified with a KT-1000 arthrometer. Eighteen patients had a normal or 1+ Lachman test and 27 had an absent or 1 + pivot shift. When compared with the results of a similar study performed on this group of patients at 2 years after surgery, there had been little subjective change in knee function. However, objectively there had been significant deterioration of the anteroposterior stability of the knees at 7 years, suggesting failure of the integrity of the repaired liga ment with time. An associated medial collateral ligament injury had a significant adverse effect both on the integrity of the anterior cruciate ligament repair and the incidence of postoperative stiffness.

To evaluate the theory that isolated posterior cruciate ligament injuries do well when treated nonoperatively, we reviewed 40 patients (mean age, 33 years at fol lowup ; average interval from injury, 6 years) who com pleted a modified Noyes knee questionnaire and were reevaluated by physical examination, radiographs, and isokinetic testing. Thirty of the injuries to the posterior cruciate ligament were sports-related. On the question naire, 65% of the patients revealed that their activity level after injury was limited and 49% stated that the involved knee had not recovered fully despite rehabili tation. Ninety percent complained of knee pain with activity and 43% complained of problems with walking. The longer the interval between injury and this followup, the lower the knee questionnaire score and the greater the radiographic degenerative changes. The patients as a group exhibited excellent muscular strength with a mean isokinetic score of 99% of the contralateral extremity. There was no correlation between isokinetic testing and knee questionnaire score. Patients with greater posterior laxity, as measured by the posterior drawer examination, appeared to have greater subjec tive complaints. Our study suggests that patients with isolated posterior cruciate ligament injuries treated non operatively may maintain excellent muscle strength, but significant symptoms and degenerative changes in crease with increasing interval from injury.

The objectives of this study were to investigate the incidence of sports injuries in Ireland and to analyze various ways of quantifying the seriousness of these injuries. A 12-month, prospective study was carried out on 324 Irish athletes involved at a high level of sports participation in one of the following categories: endur ance, contact, noncontact, or explosive sports. Results were expressed in four ways: 1) number of injuries per year; 2) days injured per year; 3) number of injuries per 10,000 hours of participation; and 4) duration of injury per 1000 hours of participation.

The average athlete sustained 1.17 acute and 0.93 overuse injuries per year and suffered the effects of sports injury for 52 days. More time was lost through overuse injuries than acute injuries. The incidence of acute injuries per 10,000 hours of participation was lowest in the noncontact sports and highest in the contact sports, but there was no difference in the incidence of overuse injuries between any of the four categories of sport. The injury rate per 10,000 hours of participation was lowest in noncontact and explosive sports and highest in contact sports. However, when expressed in terms of days lost per 1000 hours of participation, endurance sports had the lowest inci dence of time loss and explosive sports the highest.