Percutaneous medial collateral ligament release in arthroscopic medial meniscectomy in tight knees

摘要

Purpose: Visualization and surgery of tears in the posterior medial meniscus are difficult in tight knees. Iatrogenic chondral lesions might cause serious morbidity, and residual tears may result in inadequate symptom relief. We evaluated the clinical and radiological results of superficial medial collateral ligament (MCL) release during arthroscopic medial meniscectomy in tight knees. Methods: Eighteen patients [median age: 43 years (22-59); median follow-up: 8.3 months (6-12)] who underwent arthroscopic meniscectomy were included in the study. Patients with ligamentous injuries, severe chondral damage or meniscal repairs were excluded. Preoperatively, anteroposterior knee radiographs were obtained with 11-kg valgus stress using a specialized instrument. During the operation, if opening of the medial knee in 30° flexion under 11-kg valgus stress was inadequate, controlled release of the posterior portion of the MCL was performed using a 16-gauge needle. Intraoperative valgus stress was monitored using a specially designed lateral support with mounted load cell. MCL injury was evaluated both with magnetic resonance imaging (MRI) and valgus stress radiographs, which were obtained in the 1st week and 3rd and 6th months postoperatively to monitor healing of the elongated MCL. Results: In all patients, meniscectomy could be performed with adequate visualization of the posterior medial meniscus and without iatrogenic chondral injury. The median medial joint space width on valgus stress radiographs was 7.1 mm preoperatively and 9.1, 8.0 and 7.2 mm in the 1st week, and 3rd and 6th months, respectively (p < 0.0001). On MRI, the injured structure was the posterior two-thirds of the MCL. Median Lysholm score, which was 42 points before the operation, had increased to 94 points at the final follow-up (p = 0.0002). Conclusion: Controlled release of the MCL in tight knees allowed easier handling in posterior medial meniscus tears and a better understanding of tear configurations, avoiding iatrogenic chondral lesions. The MCL injury healed uneventfully. Level of evidence: IV.