Nonoperative Management Of Minimally Displaced Patellar Sleeve Fractures

Patellar sleeve fractures primarily occur in the adolescent population from a rapid contraction of the quadriceps with the knee in a flexed position. Several small case reports describe operative reduction and fixation for displaced fractures. However, there is sparse literature on nonoperative management of these injuries. Retrospective review and prospective follow-up of all patients diagnosed with patellar sleeve fracture between 1991 and 2014 at a single institution. Patients with superior pole avulsion fractures, history of prior knee surgery, and fractures managed operatively were excluded. Patients with a clinical diagnosis without support of advanced imaging were also excluded. Radiographs and magnetic resonance imaging (MRI) were reviewed for initial fracture displacement, time until fracture union, and the presence of patellar tendon ossification. Outcome was assessed using the Tegner's activity scale, Kujala's Score and the International Knee Documentation Committee (IKDC) subjective knee evaluation score at final follow-up. Eighteen nonoperatively treated distal patellar pole sleeve fractures were identified, while five patients had advanced imaging to support their diagnosis. All were males with a mean age of 15.1 (range: 12-18). Traumatic and sport-related injuries were noted in the majority of patients. Only one patient had any appreciable displacement, but still<2mm. Final radiographic evaluation revealed fracture healing without patellar tendon ossification in all patients. All five patients had full terminal knee extension and symmetric range of motion. Mean IKDC score was 96.4 (range: 82-100) mean Tegner's activity score was 60 (range: 5-8), and mean Kujala's score was 89.7 (range: 63-100) at final follow-up. Of the five cases, three patients presented in a delayed fashion, and all went on to have surgical treatment. Two required arthroscopic loose body removal, while the other had an open patellar debridement and platelet-rich plasma (PRP) injection. Minimally displaced patellar sleeve fractures can be successfully managed nonoperatively with excellent clinical outcomes. However, delayed in presentation may be associated with worse outcome. This study of case series reflects level of evidence IV.