Surgical technique of an innovative patient-specific metal implant for talar osteochondral lesions.

Purpose: Treatment strategies for osteochondral defects (OCDs) of the ankle have substantially increased over the last decade. The development of a small metallic implant to fill the defect has led to the second-generation patient-specific metal implant (Episealer Talus® Implant) designed based on computed tomography and magnetic resonance imaging images. Methods: There is a pool of patients falling into the so-called 'treatment gap', a grey zone composed of active patients with symptomatic OCDs in the context of an otherwise healthy joint, or patients with a failed primary treatment. To minimize the risk of perioperative complications, there are a series of tips and tricks that can be considered. Results: Correct execution of the operative approach, proper positioning of the guides, posterior capsule and deep deltoid ligament release and the use of Hintermann spreader allow a perfect visualization of the OCDs minimizing the risk of iatrogenic lesions. Correct execution of the medial malleolus osteotomy, release of soft tissue, proper triplanar alignment of the custom-made guide, its strong stabilization during the reaming and the use of vigorous washes minimizes the potential damage on healthy cartilage. Correct sinking of the implant is crucial; the goal is to place the Episealer Talus at least 0.5 mm below the cartilage surface. Filling a large subchondral cyst with the cancellous bone can be useful to provide better stability of the implant. Conclusion: Episealer Talus for talar OCDs possibly represents an additional tool for surgeons and patients. It is important to avoid mistakes during implant placement. Levels of Evidence: Level V, expert opinion.