Arthroscopic Treatment for Synovial Osteochondromatosis at the Knee Posterior Septum Using a Trans-Septal Approach: A Case Report

Abstract

 We treated a case of synovial osteochondromatosis in the right knee posterior septum using arthroscopy with a posterior trans-septal approach. The patient was a 64-year old female who complained of discomfort and pain upon flexion and extension, with restricted range of motion (ROM). X-ray and computed tomography imaging revealed several osteochondromas at the posterior compartment of the knee. The patient was diagnosed with osteochondromatosis of the right knee, and an arthroscopic examination was performed. Briefly, we made a posteromedial portal for arthroscopic observation by passing the arthroscope between the posterior cruciate ligament and intercondylar notch. After dissection of the posterior septum from the posteromedial portal, we created a posterolateral portal. By observation and operation from the posteromedial and posterolateral portals, osteochondromas at the posterior septum and posterior compartment of the knee were removed effectively. At a 12-month follow-up, the patient was pain-free with a full ROM. It is difficult to remove osteochondromas at the posterior compartment of the knee through the conventional anteromedial and anterolateral portals. However, a posterior trans-septal approach may be an easier way to undertake such challenging surgery.