Surgical versus Nonsurgical Treatments of Acute Primary Patellar Dislocation with Special Emphasis on the MPFL Injury Patterns.

The objective of the present study was to compare the clinical results of the surgical versus nonsurgical treatments of acute primary patellar dislocations with a medial patellofemoral ligament (MPFL) injury in the nonoverlap region with the vastus medialis oblique. In this study, 62 patients with an acute patellar dislocation and a concurrent MPFL injury in the nonoverlap region were randomly divided into two groups based on their birth years (even vs. odd years) and received either surgical or nonsurgical treatment. Of the 62 eligible patients, 30 were in the nonsurgical treatment group (Group 1) and 32 were in the surgical group (Group 2). Patellar stability tests and the Kujala knee questionnaire were performed, and radiographs were evaluated for patellar tilt and the lateral shift ratio by two blinded investigators. An osteochondral injury was noted in six (23.1%) patients from Group 1 and five (16.7%) patients from Group 2, with no statistical difference between the two groups. The mean Kujala score was 80.19 ± 5.07 and 93.57 ± 4.03 ( < 0.001) between the surgical and nonsurgical groups, respectively. The mean patellar tilt was 8.96 ± 1.64 and 6.83 ± 1.44 degrees ( < 0.001) and the lateral shift ratio was 11.08 ± 1.99 and 9.23 ± 1.96 ( = 0.001) between the surgical and nonsurgical groups, respectively. This study showed that the surgical treatment of MPFL injuries in the nonoverlap region achieved better clinical outcomes and improved subjective knee function compared with conservative therapy. Surgery should therefore be considered as the treatment of choice for these specific injuries.