Medial collateral ligament section during unicompartmental knee arthroplasty managed by direct repair and fascia lata augmentation autograft: a case report and surgical technique

The medial collateral ligament (MCL) is crucial for ensuring implant stability after unicompartmental knee arthroplasty (UKA). Intraoperative MCL lesions can cause valgus instability, affecting function and implant longevity, and thereby negatively impacting the patient's outcome. Every surgeon who performs UKA may encounter this complication in their daily practice. In this context, this case report presents a rescue technique. The existing literature does not specify a protocol for managing this complication. This article presents the first instance of accidental midsubstance section of the MCL during medial UKA, managed through primary suture and augmentation repair with a fascia lata (FL) autograft. The procedure was subsequently replicated step by step on an anatomical specimen.