Evaluation of combined arthroscopic lateral release and medial patellofemoral ligament reconstruction for the treatment of recurrent lateral patellar instability

Background
Different methods were used for the treatment of recurrent lateral patellar instability (LPI) of the knee and the combined arthroscopic lateral release and medial patellofemoral ligament (MPFL) reconstruction is an effective method of treatment.
Aim
This study aimed to evaluate the functional and radiological outcomes of treatment of recurrent LPI using combined arthroscopic lateral release and MPFL reconstruction.
Patients and methods
This prospective study was conducted on 12 patients, two male and 10 female, attending Saudi German Hospital in Saudi Arabia between March 2013 and October 2014, and the mean age was 26 years (range: 20–34) at the time of surgery. Patients with recurrent LPI confirmed by means of history, physical examination, and radiographic examinations were included in the study. Follow-up evaluation of the results after 1 year of surgery was carried out using Kujala score, Lysholm score, Tegner activity score, and the criteria of Crosby and Insall, and the rate of satisfaction was evaluated according to Nelitz.
Results
The congruence angle improved from 18.3±5.4° preoperatively to −5.0±0.4° at 1-year follow-up. The lateral patellar angle significantly improved from −7.5±4.2° preoperatively to 6.2±3.1° at 1-year follow-up. Moreover, the patellar tilt angle improved from 28.5±6.5° preoperatively to 8.2±0.7° at 1-year follow-up. The mean Kujala score increased significantly from 44.6±2.5 preoperatively to 92.4±3.6 points postoperatively (<0.05). The mean Lysholm score increased significantly from 42.8±6.4 points preoperatively to 94.4±4.2 points postoperatively (<0.05). In addition, the Tegner score improved from 2.6±0.8 points preoperatively to 6.6±0.4 points at 1-year follow-up. Evaluation using Crosby–Insall criteria after 1-year follow-up showed that 10 (83%) patients had excellent results and two (17%) patients had good results. According to Nelitz criteria, eight (67%) patients were very satisfied with surgery, three (25%) patients were satisfied, and one (8%) patient partially satisfied. No postoperative vascular or neurological complications were found and no patient had patellar redislocation. One patient had superficial infection that improved with frequent dressing.
Conclusion
The double bundle graft technique used in this study for the reconstruction of MPFL provides proper anatomical position of the femoral fixation of the graft and gives stable tendon-to-bone fixation with early healing and offers a successful outcome that allows an early rehabilitation and return to full activity.