Objective To investigate the effectiveness of arthroscopic medial retinaculum plication (MRP) for acute patellar dislocation (APD) in adolescents. Methods Between March 2007 and June 2011, 24 adolescent patients suffering from APD were treated by arthroscopic MRP. There were 14 males and 10 females, aged 8-18 years (mean, 12.7 years). The location was the left knee in 16 cases and the right knee in 8 cases. Injury was caused by sports in 19 cases, by traffic accident in 4 cases, and by heavy bruising in 1 case. The duration from injury to operation was 3 to 21 days with an average of 7.8 days. The results of floating patella test and dislocation apprehension test were both positive. MRI examination showed the arthroedema in all cases; associated injuries included medial retinaculum injury in 20 cases, medial patellar injury in 8 cases, and meniscus tear in 5 cases. Results All incisions healed by first intention without complication of infection or neurovascular injury. All the patients were followed up 12-36 months (mean, 14.6 months). Only 2 patients suffered from patellar re-dislocation at 4 months and 6 months after operation respectively. The knee joint activity returned to normal at 12 months. The Lysholm, Kujala, and International Knee Documentation Committee (IKDC) scores at 3 and 12 months after operation were significantly higher than those before operation (P lt; 0.05), and the scores at 12 months were significantly higher than those at 3 months (P lt; 0.05). Conclusion Treatment of APD with arthroscopic MRP has the advantages of minor trauma and good knee functional improvement. The technique can decrease incidence of patellar re-dislocation in adolescent.
Objective To evaluate an improving operative procedure and the cl inical results of arthroscopically assisted treatment for acute patellar dislocation. Methods Between April 2006 and March 2009, 22 patients (25 knees) with primary acute complete dislocation of the patella underwent an improving arthroscopic operation, release of lateral retinaculum and suture of medial capsule and retinaculum structure. There were 5 males and 17 females with an average age of 23.6 years (range, 14-34 years). Three patients had bilateral procedure. Eleven left knees and 14 right knees were involved. The disease duration was 1-10 days with an average of 5.9 days. All patients had lateral dislocation; of them, 14 patients showed reduction without treatment, and 8 patients showed dislocation at admission and were given close manipulative reduction. The results were positive for apprehension test in all patients with the l imitation of passive motion and for Ballottable Patella Sign in 15 cases. Lysholm score, visual analogue scale (VAS) score, and Insall scale were adopted to evaluate the effect. Results All incisions healed by first intention. All the patients were followed up 12-36 months (17 months on average). During the first 3 months after operation, sunken skin in the puncture point medial to the patella was observed in 12 knees; 10 knees suffered pain of the soft tissue lateral to the patella; 15 knees felt tense in the soft tissue medial to the patella, however, all these problems disappeared or recovered gradually after rehabil itation and conservative treatment. No recurrence of dislocation was observed during the follow-up. Lysholm score was significantly improved from preoperative 67.3 ± 5.7 to postoperative 96.6 ± 4.5 (t=3.241, P=0.003) and VAS score from 6.5 ± 0.5 to 1.8 ± 0.4 (t=2.154, P=0.040). According to Insall scale, the results were excellent in 18 knees, good in 5 knees, and fair in 2 knees at 1 year after operation with an excellent and good rate of 92%. Conclusion The improving procedure of arthroscopically assisted treatment for acute patellar dislocation is a minimally invasive operation and has a number of benefits. Its short-term cl inical outcome was satisfactory.