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Fifty-two patients who had an extraarticular reconstruction for anterior cruciate ligament (ACL) insufficiency were interviewed at an average of 11.4 years after their reconstruction. During the follow-up period, 4 patients (8%) had intra-articular reconstructions for persistent instability or re-injury, and another 4 (8%) had arthroscopic surgery for meniscal lesions. The mean Lysholm score at follow-up was 76.9. Of the 52 patients, 5 had had subsequent surgery during the follow-up period. In the remaining 47 patients, the results were excellent in 14 (29%), good in 10 (23%), fair in 7 (15%), and poor in 16 (33%). Patients operated on acutely (<6 weeks after injury) had a mean score of 82, whereas patients operated on more than 6 weeks after injury had a mean score of 75. Adding those patients who required subsequent reconstructions for persistent instability (4 knees) and those who obtained fair and poor results yielded an alarming rate of unsatisfactory results (52%). On the basis of these findings, we believe the lateral extraarticular reconstruction is not an acceptable form of treatment for the functionally unstable knee.

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We prospectively determined the risk of initial stinger experience in a group of college football players while considering the presence of cervical canal stenosis and each player's position, playing time, and body type. Prospective analysis revealed a 7.7% incidence of initial stinger experience. The average Torg ratio for all players was 0.924 +/- 0.122, with the seventh cervical level being the narrowest. Initial stinger experience depended on position played and body type. The Torg ratio did not influence initial stinger occurrence. Players who experienced multiple stingers, however, had significantly smaller Torg ratios than players experiencing only one stinger (0.75 versus 0.87). A Torg ratio of 0.70 may be a more statistically and clinically appropriate threshold for determining significant cervical stenosis and advising collegiate athletes of their risk of experiencing recurrent stingers.

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To determine the necessity of extensive supervised therapy, we reviewed the records of 39 consecutive patients who underwent arthroscopic anterior cruciate ligament reconstruction using mid-1/3 bone-patellar tendon-bone autograft, followed by a minimal therapy program. This study group was subdivided into a noncompliant group averaging 1.7 visits over 6 months (range, 0 to 5), (subgroup I), and a minimally compliant group averaging 12 visits over 6 months (range, 5 to 24), (subgroup II). Thirty patients who underwent similar surgeries and postoperative protocols, but participated in an extensive supervised outpatient therapy program, served as controls. The control group was fully compliant and averaged 60 visits over 6 months. After 6 months, the minimally compliant study subgroup was equivalent to the fully compliant control group in Lysholm score, patient satisfaction, and return to preoperative activity level. Both of these groups fared better in all of these indices than did the noncompliant subgroup. These results suggest that extensive supervised rehabilitation does not afford a measurable advantage over a minimally supervised program of two visits monthly. Complete noncompliance, however, was associated with suboptimal outcome.

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To clarify their usefulness in screening massive rotator cuff tear, routine radiographs of the shoulder were compared in three groups: (1) shoulders with a massive rotator cuff tear (MRCT), (2) shoulders with a small full-thickness rotator cuff tear (SRCT), and (3) normal control shoulders. Two different statistical methods were employed to assess the gradation (order) of correlation in 83 shoulders (22 were MRCTs, 31 with SRCTs, and 30 controls). Superior migration of the humerus and deformity of the greater tuberosity showed by far the more significant contribution to MRCT than did other abnormalities. When the shoulders were screened for these two abnormalities, the sensitivity was 78% (21/27) and specificity was 98% (55/56).

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OBJECTIVE: To clarify the efficacy of MRI for the evaluation of rotator cuff impingement beneath the coracoacromial arch, MRI findings were correlated with confirmed full-thickness rotator cuff tears (FTRCTs). MATERIALS AND METHODS: Thirty-four shoulders with FTRCT and 49 control shoulders without FTRCT were selected for this study. Direct measurement of the subacromial space (SAS) and MRI grading of SAS and subacromioclavicular space (SACS) were correlated with FTRCT. In addition, the MRI impingement score (sum of SAS grade and SACS grade) was correlated with age and FTRCT. RESULTS: Direct measurement of the SAS showed poor correlation with FTRCT. The SAS grade showed significant correlation with FTRCT; however, SACS grade showed poor correlation. Shoulders with higher MRI impingement scores were associated with FTRCT in patients over 40 years of age. CONCLUSION: The MRI sign of rotator cuff impingement is fairly reliable and helpful in discriminating patients with FTRCT, especially older patients.

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In a multi-institution study, 18 knees with complete quadriceps tendon ruptures (QTRs) were reviewed to analyze the cause of failure in radiographic diagnosis. Only 6 of the 18 knees were diagnosed correctly initially. This occurred even though almost all knee radiographs showed more than three abnormalities compatible with QTR (obliteration of quadriceps tendon, suprapatellar mass, suprapatellar calcific density, or patella baja). Of the 12 diagnostic failures, only 3 were considered to be complete failure. Nine primary reports (50%) were classified as incomplete diagnosis and could be correctly diagnosed if the attention of radiologists was focused to the quadriceps mechanism. We conclude that better understanding of radiographic abnormalities in QTR is necessary for the improvement of primary radiological diagnosis.

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To identify any correlation between the distribution of occult bone lesions and meniscoligamentous injuries, magnetic resonance images of 333 patients with traumatic knee joint disease were reviewed. Bone lesions of the knee were commonly associated with medial meniscal injuries and/or anterior cruciate ligament injuries. While knees with bone lesions showed a higher incidence (P < 0.05) of anterior cruciate ligament injury than knees without bone lesions, the presence of a lateral femoral condylar lesion resulted in a significantly higher incidence of anterior cruciate ligament injuries (P < 0.01). However, no significant positive correlation was found between other occult bone lesions and meniscoligamentous injuries.

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Surveys were sent to 84 children's hospitals and 397 sportsmedicine clinics to characterize the care available for the child athlete (aged 4 to 12 years); they were completed by 209 facilities (43% response rate). Fourteen of the facilities had a sportsmedicine clinic specifically for children; care was available for the child athlete in an additional 46 facilities, but less than 10% of the clinic visits were made by athletes aged 4 to 12 years. All responding clinics were further characterized by location, length of operation, composition, referral base, profitability and funding, etc. Although there are few sportsmedicine clinics specifically for children, many facilities provide experienced personnel in existing clinics to care for young athletes.

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A 33 item multiple choice questionnaire was circulated; completed questionnaires from 1505 runners (1130 male and 375 female) were obtained. Questions focused upon training, injuries sustained, and medical care. Biomechanical imbalances such as leg length inequality appear to be a major contributing factor to running injuries. Correction of an underlying biomechanical defect may be important in the treatment of many running injuries. Female runners were found to be more susceptible than males to stress fractures at higher mileages. The cause of this increased incidence may be attributable to lower bone mineral density levels as a result of hormonal factors. Factors such as running surface, age and stretching techniques do not appear to play a significant part in the pathogenesis of running injuries.

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We have presented a brief overview of therapeutic exercise and patellofemoral biomechanics and their relation to a rehabilitation program of the nonoperative patient with patellofemoral dysfunction. This was followed by a specific protocol for extensor mechanism reconstruction, which can in part be applied to the nonoperative patient with a more vigorous lifestyle. Self-discipline and perseverance on the part of the patient are the only factors that cannot be controlled; yet, without these, no surgical procedure or rehabilitation program will ever succeed.

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The in vitro breaking force of a braided nylon looped-suture tendon juncture designed to decrease tying time was compared with the breaking force of the modified Kessler and Bunnell techniques. Repaired with either braided nylon or tetrafluoroethylene, porcine digiti quarti propius tendons were tested to single cycle failure on a MTS hydraulic testing machine. The results showed that the looped-suture technique had a mean breaking force that was statistically indistinguishable from that of the Bunnell technique regardless of suture material. However, the breaking forces for the looped suture and Bunnell techniques were statistically greater for both suture materials when compared with the modified Kessler technique. The resistance to gap formation for the looped suture was found to be intermediate between the Bunnell technique and the modified Kessler technique.

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The biomechanics of the biceps femoris tendon transfer were determined from four fresh, frozen extremities. All transfers involved the proximal and anterior advancement of a selected portion of the tendon to a position superficial to the lateral collateral ligament. The rotational torque and flexion force were measured before and after the transfer with the knee positioned at 10 degrees, 20 degrees, 30 degrees, and 45 degrees of flexion, in neutral and 5 degrees internal rotation. Although more specimens need to be tested for statistical confirmation, the transfer of the superficial portion of the biceps tendon resulted in average decreases of 2% and 15% in the rotational and flexion capacity of the biceps, respectively. Biomechanically, the functional lever arm of the transferred tendon about the longitudinal (internal-external rotation) axis was essentially unchanged, while the functional lever arm about the sagittal (flexion-extension) axis was decreased slightly. The total transfer of the biceps tendon resulted in an increase of 28% in the rotational capacity, while the flexion capability was decreased an average of 75%. In addition, the total transfer resulted in the biceps becoming an extensor at 10 degrees and 20 degrees of flexion, which could actually worsen the instability. Thus, following the total transfer, the functional level arm about the sagittal axis was decreased, while the functional lever arm about the longitudinal axis was increased. In summary, neither the partial nor the total transfer of the biceps femoris tendon superficial and anterior to the fibular collateral ligament appeared to be a biomechanically effective ancillary for the treatment of anterolateral rotatory instability.

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A retrospective study was conducted to evaluate the long-term effectiveness of wrist arthroplasties in patients with various arthritic conditions. A total of 39 wrist arthroplasties were performed in 29 patients (average age, 52.5 years) by the orthopedic staff at Tulane University School of Medicine. Rheumatoid arthritis was the major presenting diagnosis in 84.6% of these operative cases and pain was the most common indication for surgery (79.5%). Postoperative relief of pain was reported in all of the cases reviewed, with an average follow up period of 51.2 months (range, 12 to 118 months). A group of 15 patients who were examined clinically had an average grip strength of 19.2 lb (range, 6 lb to 45 lb). Pinch measurements averaged 1.9 lb and arc of motion averaged 59.5 degrees (range, 20 degrees to 100 degrees) for these patients. Postoperative complications included dislocation (3 cases), fracture of the prosthesis (2 cases), and infection (2 cases). No complications were observed in 32 (82.1%) of the 39 cases reviewed. This retrospective study revealed that at an average follow up period of 51.2 months, pain relief was excellent and patient acceptance was good, with 94.9% of the wrists having been improved by the procedure. The majority (82.1%) of the cases were free of complication. It is concluded from this study that wrist arthroplasty is a viable alternative to wrist arthrodesis.

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Ultra low temperature isotropic (ULTI) carbon-coated polyester suture material was evaluated histologically and mechanically in dogs. These results were compared to those obtained for uncoated polyester and polybutylate coated polyester. The suture materials were used in the repair of the surgically incised medial collateral ligament and subcutaneous tissues to evaluate the potential of the carbon-coated system for ligamentous repairs. Following surgery, the dogs were sacrificed at periods of 1-48 weeks postoperatively for evaluation of tissue biocompatibility and mechanical strength of the materials. The polybutylate-coated polyester suture broke at lower force levels than did comparable sizes of uncoated or carbon-coated polyester. All three types showed a high retention (greater than 98%) of mechanical strength at 48 weeks, often exhibiting an increase in tensile strength due to tissue ingrowth. The histologic response to carbon-coated polyester was equal to or better than the response to either the uncoated polyester or polybutylate-coated polyester. A greater degree of tissue growth into the carbon-coated material was evident at most time periods following an initial acute inflammatory response which was also present in the other materials.

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Hand injuries in athletes are very common and usually do not prevent active participation in sports. For this reason, long-term permanent disability and permanent loss of function may develop if these injuries are not recognized and treated properly. The majority of metacarpal and phalangeal joint injuries respond well to closed aggressive early treatment, followed by intensive therapy and protective splinting, which allow the athlete to continue his or her sport participation without the undesirable effects of long-term or permanent loss of function to the hand.

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Five fresh nonembalmed elbows were tested for resistance to valgus stress in their anatomic state, after radial head resection, and after insertion of Silastic and polymethylmethacrylate (PMMA) radial head replacements. The resistance to valgus stress was found to be reduced an average of 28% after radial head resection. The PMMA and Silastic implants restored valgus stiffness an average of 86% and 78% respectively, as compared to intact elbow values for corresponding flexion angles. Testing in pronation, supination and neutral forearm rotation demonstrated no difference in valgus stiffness. For each elbow, resistance to valgus stress was greatest at full extension and dropped approximately 30% at all other flexion angles as compared to corresponding full extension value. These data support the concept of the radial head as a stabilizer to valgus stress in the in vitro elbow. Further, this data demonstrated the ineffectiveness of current radial head replacement systems in restoring this biomechanical function and suggest that the use of a stiffer implant material may be beneficial in resisting valgus stress. Additional testing is indicated to determine the performance of a stiffer implant at the clinical and biological levels.

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Osteolysis of the distal clavicle was diagnosed in a young male athlete following many years as a baseball pitcher with a supplementary weightlifting program. There was no history of ligamentous injuries, contusions, fractures or separation of the acromioclavicular joint. As such, this case was categorized as "atraumatic" osteolysis. Non-decalcified histologic sections from the resected clavicle suggest that the pathogenesis of this atraumatic osteolysis arose from the synovium.

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The running shoe provides shock absorption and motion control for the runner. The change in shock-absorption properties has been studied as a function of miles run. Different models of running shoes encompassing various manufacturers' models and price ranges were mechanically tested to simulate the repeated heel strikes of running. The energy absorbed by the shoes was determined from the area under the load deformation curve at various intervals to the equivalent of having run 500 miles. Shoes were also tested at similar intervals after having been worn by volunteers during normal training. A difference of approximately 33 per cent in the initial shock absorption was observed in the different shoe models tested. In general, the mechanically tested shoes retained approximately 75 per cent of their initial shock absorption capability after 50 miles and approximately 67 per cent after 100 to 150 miles. Between 250 and 500 miles, the shoes retained less than 60 per cent of their initial shock-absorption capacity. The shoes tested after having been worn during running by volunteers had similar but less severe degradation characteristics. These shoes tended to retain approximately 70 per cent of the initial shock absorption characteristics were apparent based upon either shoe price or manufacturer. In addition, shoes that exhibited superior initial shock absorption capability often had more rapid degradation characteristics.

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The change in shock absorption properties of running shoes was evaluated as a function of miles run. Different models of running shoes encompassing a wide range in retail price were obtained and mechanically tested to simulate the repeated heel strikes of running. The energy absorbed by the shoes was determined from the area under the load deformation curve at the equivalent of 0, 5, 10, 25, 50, 75, 100, 125, 150, 200, 250, 300, and 500 miles of running. Shoes were also tested at similar intervals after having been worn by volunteers during normal training. An approximate 33% difference in the initial shock absorption was observed in the different shoe models. In general, the shoes retained approximately 75% of their initial shock absorption capability after 50 miles of simulated running, and approximately 67% after 100 to 150 miles. Between 250 and 500 miles the shoes retained less than 60% of their initial shock absorption capacity. No differences in shock absorption characteristics were apparent based upon either shoe price or the manufacturer model. The results of shoes tested by the volunteer runners also showed a marked reduction in shock absorption with mileage. The loss, however, was not as great as in the machine-simulated running, with approximately 70% of initial shock absorption retained at 500 miles.

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