BACKGROUND: Arthroscopic release of the vastus lateralis tendon for treatment of recurrent patellar dislocation has been criticized on the grounds that it may weaken the quadriceps. HYPOTHESIS: Quadriceps strength and outcome measures improve after arthroscopic release of the vastus lateralis tendon in patients with documented patellar dislocation. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty patients who had recurrent patellar dislocation underwent arthroscopic lateral retinacular release that included a complete release of the vastus lateralis tendon from the superior pole of the patella and were observed prospectively. Bilateral quadriceps strength was tested preoperatively and at follow-up with an isokinetic dynamometer. Patients also completed the International Knee Documentation Committee Subjective Knee Form and the Short Form-36 preoperatively and postoperatively. RESULTS: Follow-up averaged 27 months (range, 24-43 months). There were no redislocations. Mean quadriceps strength improved by a mean of 28% (from 32.3 to 41.4 N x m). The mean quadriceps torque ratio (involved/uninvolved) improved significantly from a preoperative value of 63% (31/51 N x m) to 80% (42/52 N x m) at follow-up (P = .017). Fourteen patients (70%) increased quadriceps torque, and 6 patients (30%) decreased quadriceps torque. Only 1 patient failed to improve on International Knee Documentation Committee and Short Form-36 scores. The International Knee Documentation Committee scores improved from 45 points preoperatively to 76 points at follow-up (P = .001). The Short Form-36 physical component summary scores improved from 38 points preoperatively to 50 points at follow-up (P = .007), and the Short Form-36 physical functioning subscale scores improved from 53 points to 86 points (P = .015). CONCLUSION: Arthroscopic release of the vastus lateralis tendon and lateral patellar retinaculum in patients with recurrent patellar dislocation can improve quadriceps strength and knee function.
BACKGROUND: Arthroscopic release of the vastus lateralis tendon for treatment of recurrent patellar dislocation has been criticized on the grounds that it may weaken the quadriceps. HYPOTHESIS: Quadriceps strength and outcome measures improve after arthroscopic release of the vastus lateralis tendon in patients with documented patellar dislocation. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty patients who had recurrent patellar dislocation underwent arthroscopic lateral retinacular release that included a complete release of the vastus lateralis tendon from the superior pole of the patella and were observed prospectively. Bilateral quadriceps strength was tested preoperatively and at follow-up with an isokinetic dynamometer. Patients also completed the International Knee Documentation Committee Subjective Knee Form and the Short Form-36 preoperatively and postoperatively. RESULTS: Follow-up averaged 27 months (range, 24-43 months). There were no redislocations. Mean quadriceps strength improved by a mean of 28% (from 32.3 to 41.4 N x m). The mean quadriceps torque ratio (involved/uninvolved) improved significantly from a preoperative value of 63% (31/51 N x m) to 80% (42/52 N x m) at follow-up (P = .017). Fourteen patients (70%) increased quadriceps torque, and 6 patients (30%) decreased quadriceps torque. Only 1 patient failed to improve on International Knee Documentation Committee and Short Form-36 scores. The International Knee Documentation Committee scores improved from 45 points preoperatively to 76 points at follow-up (P = .001). The Short Form-36 physical component summary scores improved from 38 points preoperatively to 50 points at follow-up (P = .007), and the Short Form-36 physical functioning subscale scores improved from 53 points to 86 points (P = .015). CONCLUSION: Arthroscopic release of the vastus lateralis tendon and lateral patellar retinaculum in patients with recurrent patellar dislocation can improve quadriceps strength and knee function.
Authors: Filippo Migliorini; Christian Lüring; Jörg Eschweiler; Alice Baroncini; Arne Driessen; Filippo Spiezia; Markus Tingart; Nicola Maffulli Journal: Life (Basel) Date: 2021-03-30