Abstract / Summary
Abstract Background Osteonecrosis of the lateral femoral condyle is a rare condition, and the optimal surgical management for extensive, deep lesions in young or active patients remains a matter of debate. Both unicompartmental knee arthroplasty and total knee arthroplasty raise concerns regarding implant longevity in this population, making joint-preserving surgical strategies desirable. Case presentation A 52-year-old man with a history of 10-year corticosteroid use was presented with pain on the lateral side of his left knee. Massive osteonecrosis of the lateral femoral condyle (approximately 25 × 30 × 15 mm), with concomitant mild valgus malalignment (hip-knee-ankle angle 4°) and a horizontal tear of the lateral meniscus was detected with the radiographical, computed tomography, and magnetic resonance images. The patient underwent a combination of autologous osteochondral en bloc transplantation (OCET) of a mass graft which was harvested from the medial trochlea (approximately 20 × 25 × 18 mm) and fixed with four double-threaded screws, arthroscopic lateral meniscus repair, and medial closing-wedge distal femoral osteotomy (DFO) with a correction angle of 5°. At two years postoperatively, we confirmed solid union at both the osteotomy and graft sites with no loss of alignment correction (femorotibial angle 176°, hip-knee-ankle angle -2°), and observed marked improvement in his knee pain, the visual analogue scale score, and all subscales of the Knee Injury and Osteoarthritis Outcome Score. Conclusions The combination of OCET and DFO were shown to be an effective and reliable joint-preserving treatment strategy for extensive and deep osteonecrosis of the lateral femoral condyle with concomitant valgus malalignment in young, active patients, while the long-term follow-up is necessary to evaluate durability. Clinical trial number Not applicable.