Lateral retinacular release in patellofemoral subluxation. Indications, results, and comparison to open patellofemoral reconstruction.

A consecutive series of patients who have undergone arthroscopy and lateral retinacular release for patellofemoral subluxation was evaluated so that the results could be compared to an earlier series of open patellofemoral reconstructions. Of 96 patients, 4 had bilateral releases; therefore, 100 knees were evaluated. The average age was 28 years. Specific symptoms and signs were reviewed. All patients were initially treated conservatively with specific exercises. Failure of the exercise program to improve symptoms significantly, the patient's inability to perform normal daily activities, or expected associated pathology were indications for surgery. The surgical technique consisted of arthroscopy with treatment of associated pathology and lateral retinacular release using the Smillie meniscotome through the inferior lateral portal. The patella could be tilted approximately 90 degrees medially when the release was accomplished. Pain, function, and patellar instability were evaluated preoperatively and postoperatively by signs of tenderness on the retinaculum or bone, patellar mobility, effusion, muscle atrophy, and tone. Range of motion was also evaluated. Average followup was 36 months. When evaluated subjectively by the patients, pain improved from a mean preoperative grade of 3.4 to 1.7 postoperatively, function improved from 3.4 to 1.7, and instability from 3.4 to 1.6. Objective evaluation found that tenderness on the patella improved from a mean preoperative grade of 3.3 to 1.7 postoperatively. Tenderness on the retinaculum improved from 3.2 to 1.7. Patellar mobility improved from 3.3 to 1.7. Effusion dropped from 3.2 preoperatively to 1.5 postoperatively; quadriceps atrophy from a mean preoperative grade of 3.2 to 1.5, and quadriceps tone from 3.2 to 1.6.(ABSTRACT TRUNCATED AT 250 WORDS)