Knee-to-Ankle Mosaicplasty for the Treatment of Osteochondral Lesions of the Ankle Joint

Background: Osteochondral lesions are frequently seen in athletes after ankle injuries. At this time, osteochondral autologous transplantation (OATS, mosaicplasty) is the only surgical treatment that replaces the entire osteochondral unit in symptomatic lesions. Purpose: To evaluate the clinical and radiological midterm to long-term outcome of ankles treated with knee-to-ankle mosaicplasty. Study Design: Case series; Level of evidence, 4. Methods: Clinical evaluation consisted of patient satisfaction, pain evaluation (visual analog scale [VAS]), American Orthopaeclic Foot and Ankle Society (AOFAS) ankle score, sports activity score, range of motion, the radiological evaluation of magnetic resonance imaging (MRI), and single photon emission computed tomography-computed tomography (SPECT-CT) analysis of both the ankle and the knee joint. Results: Twelve of 21 patients (mean age, 43 years; male, 8; female, 4) were available for latest follow-up (mean, 72 months). At follow-up, patients reported a satisfaction rate of good to excellent in 92% (n = 11) and poor in 8% (n = 1). The average VAS pain score was 3.9 (preoperative, 5.9; P = .02), AOFAS ankle score significantly increased from 45.9 to 80.2 points (P < .0001), sports activity score remained significantly decreased with 1.25 (preinjury level, 2.3; P = .035), and ankle dorsiflexion was significantly reduced (P = .003). Knee pain was reported in 6 patients (50%). Radiologically, recurrent lesions were found in 10 of 10 cases (100%) and some degree of cartilage degeneration and discontinuity of the subchondral bone plate in 100%. Conclusion: Indications for mosaicplasty with a plug transfer from the knee to the talus must be considered carefully, as at midterm, moderate outcome and considerable donor-site morbidity may be found.