Background: Symptomatic osteochondral lesions of the talus (OLTs) often require surgical intervention. There are various surgical methods. A generally valid, stage-dependent therapeutic algorithm does not exist. The aim of our study is to show long- term results of an alternative technique that combines retrograde drilling, debridement performed under arthroscopic visualization, and autologous bone grafting.
Methods: The surgical technique was performed in 24 patients with medial or lateral OLTs, and the data were analyzed retrospectively. In our technique, the affected subchondral bone was overdrilled retrogradely and resected under arthroscopic visualization (ossoscopy) without violating the cartilage. The resulting defect was filled with autologous bone from the medial tibia metaphysis. Outcome parameters were the numeric rating scale (NRS), the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and range of motion (ROM). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was assessed and a possible correlation with the clinical outcome scores was calculated. Data concerning complication rates were also collected.
Results: The mean surface size of the OLTs was 0.9 ± 0.3 cm2. The mean follow-up was 89 months. The AOFAS score improved significantly from 57.7 points preoperatively to 88.8 points at the final follow-up (P < .0001). The pain value measured by the NRS decreased significantly from 8 to a pain level of 2. ROM improved in 37.5% of the patients for dorsiflexion and 29.2% for plantarflexion. There were no significant correlations between the MOCART score and the AOFAS score or the pain value on NRS.
Conclusion: Retrograde drilling, ossoscopy, and autologous bone grafting for OLTs is a promising technique with good long-term results. The patients' satisfaction rate, especially in OLT stages 2 and 3, was excellent.
Level of evidence: Level IV, case series.
Keywords: OLT; autologous bone grafting; ossoscopy; osteochondral lesion of talus; retrograde drilling.