Treatment of recurrent patellar instability with a modification of the Roux-Goldthwait technique.

Recurrent instability of the patella may be a significant disability in the childhood and adolescent population. Numerous surgical procedures to address this instability have been described, with variable outcome. This has led to considerable confusion in the literature as to how to treat patellofemoral problems in children. This study retrospectively reviews 30 knees in 20 patients with chronic recurrent patellar instability who were treated with a modified Roux-Goldthwait technique including the release of contracted lateral structures by a single surgeon over a 13-year period, with an average of 6.2 years follow-up. By Insall's criteria, 26 knees had an excellent result, 3 good result, and 1 fair result. Ten patients evaluated using a dynamometer showed that strength achieved in the operated leg was greater than 90% in 8 patients and greater than 80% in 2 patients. Here, we report upon a single operation to treat patellar instability performed in the pediatric population with consistently excellent results.

Arthroscopically assisted central physeal bar resection.

Thirty-seven central physeal bars were removed with an arthroscopically assisted technique. Thirty children (32 cases) have been followed to maturity or physeal closure. There were 19 boys and 11 girls, aged 4-14 years (mean, 9.5 years). Site of arrest was distal femur (15), proximal tibia (9), distal tibia (6), and distal radius (2). Mean follow-up was 6.5 years (range, 2-12 years). Adequate longitudinal growth was realized in 21 patients (70%) just after bar resection. Five patients (17%) required osteotomy, lengthening, or epiphysiodesis in addition to bar resection. In 4 patients (13%), bar resection failed. Failures occurred in those patients whose source of growth arrest was infection (3) or degree of physeal trauma approached 50% (1 case). This is the first series that studies and documents the efficacy of the arthroscope in central physeal bar resection. It provides the best visualization with minimal morbidity. The technique is described, including a discussion of technical tips and pitfalls.

Treatment of ankle instability in children and adolescents with a modified Chrisman-Snook repair: a clinical and patient-based outcome study.

Ligamentous injuries to the lateral ankle complex, although rare in the child with open physes, increase with age and are seen with considerable frequency in late childhood and adolescence. In athletic, ligamentously lax individuals, recurrent sprains may lead to ligament attenuation and instability. When instability becomes chronic and interferes with everyday activity, reconstruction is indicated. The literature on reconstruction addresses primarily the adult population, with minimal guidance in treating the child and adolescent. The authors report their experience with 48 reconstructions performed in patients aged 8 to 17 years (mean 14.5 years) over a 12-year period. Mean follow-up was 6.5 years. All patients failed to respond to conservative treatment, including casting or bracing and physical therapy. All had disabling instability. All had a positive drawer sign clinically, and all but one had significant talar tilt on preoperative stress radiographs. A modification of the Chrisman-Snook procedure was used. Forty-four ankles in 38 patients were available for clinical and radiographic re-evaluation. One patient with generalized systemic ligamentous laxity required bilateral repair for failure of previous Evans procedures 8 years earlier; the remaining patients had primary repairs and remain asymptomatic. Each has a negative drawer sign and a reduction of talar tilt from a preoperative average of 14.5 degrees to a postoperative average of 4 degrees, based on stress radiographs. An outcomes questionnaire was administered to all patients, who subjectively rated their pain and instability at extremely low levels (1/10) and their function at a high level (8/10). All patients had their expectations met regarding the results of surgery. There was no radiographic evidence of degenerative arthritis at follow-up. The authors recommend this as an excellent means of treating children with chronic ankle instability who have failed to respond to conservative treatment. The authors have modified Chrisman's procedure by using a much smaller incision and improved graft isometry.

Animal models for spinal fusion.

Animal models for spinal fusion are essential for preclinical testing of new fusion methods and adjuncts. They allow for control of individual variables and quantification of outcome measures. Model characteristics are considered. Preclinical experiments to evaluate proof of concept, feasibility, and efficacy are generally studied in an orderly progression from smaller to larger animal models with an evolving cascade of evidence which has become known as the "burden of proof". Methods of fusion analysis include manual palpation, radiographs, computed tomography, histology, biomechanical testing, and molecular analysis. Models which have been developed in specific species are reviewed. This sets the stage for the interpretation of studies evaluating bone graft materials such as allograft, demineralized bone matrices, bone morphogenetic proteins, ceramics, and others with consideration of the variables affecting their success. As evidence accumulates, clinical trials and applications are defined.

Arthroscopic treatment of septic arthritis in a patient with posterior stabilized total knee arthroplasty.

We report on a case of arthroscopic treatment of septic arthritis of the knee in a 73-year-old woman with a posterior stabilized knee endoprosthesis. Six months after arthroplasty of the right knee joint because of osteoarthritis, the patient experienced an erysipelas of the right lower leg after a cat bite. Although given intravenous antibiotic therapy, the patient developed septic arthritis of the right knee. Pasteurella multocida could be identified as the causative organism. The joint infection was classified as stage I according to Gächter. Via arthroscopic joint debridement, partial synovialectomy, the use of continuous irrigation-suction drains, and intravenous antibiotic therapy, the empyema could be cured without removal of the total endoprosthesis of the right knee.

Thromboembolic complication after arthroscopic shoulder surgery.

Thromboembolic complications after arthroscopic shoulder surgery are very unusual and need thorough investigation of the possible origin. In this case of venous pulmonary thromboembolism after arthroscopy of the shoulder, neither a hint of coagulopathy nor an anatomic abnormality could be found that explains this complication. Therefore, irritation of the subclavian vein caused by compression by the motor-driven shaver is probably one cause for our thromboembolic complication. Careful attention to positioning, fluid management, and use of traction, as well as an appreciation of shoulder anatomy to select portal placement will help decrease the common complications associated with shoulder arthroscopy. A further option to prevent thrombembolic complications in shoulder arthroscopy patients might be prophylaxis with a low-weight heparin in patients with risk factors. In conclusion, awareness of uncommon complications such as deep venous thrombosis and pulmonary embolism will help the orthpaedic surgeon promptly diagnose and treat these problems.

Neuromuscular function in athletes following recovery from a recent acute low back injury.

STUDY DESIGN: Observational case control design. OBJECTIVES: To examine muscle response to sudden trunk loading in athletes with and without a recent history of acute low back injury (LBI). BACKGROUND: Impaired neuromuscular function is associated with chronic low back pain. This study examined whether such impairment persists after recovery from an acute LBI. METHODS AND MEASURES: Seventeen athletes who had a recent history of acute LBI and 17 matched healthy controls were tested. At the time of testing (mean = 56 days postinjury, range = 7-120 days postinjury), all athletes were symptom free and had returned to regular competition. Subjects performed isometric exertions in trunk flexion, extension, and left and right lateral bending against a trunk restraining cable. Upon reaching the target isometric force, the cable was released to impose sudden loading on the lumbar spine. Surface EMG signals from 12 major trunk muscles were recorded. The shut-off and switch-on latencies and number of muscles responding to sudden loading were compared between the 2 groups. RESULTS: In all 4 testing directions, the athletes with a recent history of acute LBI shut off significantly fewer muscles and did so with delayed latency. On average, the injured subjects shut off 4.0 out of 6.0 (SD = 1.3) muscles compared to 4.6 out of 6.0 (SD = 1.3) muscles in the control group. The average muscle shut-off latency was 71 (SD = 31) milliseconds for the injured and 50 (SD = 21) milliseconds for the control subjects. No differences were found in number or latency of muscles switching on. CONCLUSIONS: These objective measures of neuromuscular function indicated an altered muscle response pattern to sudden trunk loading in athletes following their clinical recovery from a recent acute LBI.