Role of Osteotomy and Tunnel Bone Grafting in Chronic Medial and Lateral Knee Injuries

Abstract

Coronal plane alignment deformities of the lower extremity are often neglected in the evaluation and treatment of chronic posteromedial (PMC) and posterolateral corner (PLC) injuries. Genu varus, valgum, and recurvatum deformities can increase the likelihood of graft failure following knee ligament reconstruction. Abnormal and excessive vector forces act across the grafts if these deformities remain undiagnosed, resulting in stretching and failure of the grafts. A thorough evaluation should include a complete physical exam and radiographic imaging protocol that includes long limb alignment and stress radiographs of the knee. Correction of these deformities requires extensive preoperative planning to determine in which planes and how much correction needs to be performed via an osteotomy. A distal femoral opening wedge osteotomy is recommended to treat genu valgus deformity. A medial opening wedge osteotomy is recommended to correct genu varus deformity. In cases of combined superficial medial collateral ligament (sMCL) and PLC deficiencies, a biplanar opening wedge anterolateral opening wedge osteotomy may be indicated. These procedures should all be performed using a combination of preoperative planning and intraoperative fluoroscopy to minimize the risk of complications. In the setting of failed primary reconstructions due to an undiagnosed alignment deformity, an osteotomy and tunnel bone grafting procedure should be performed as part of a staged procedure. Early outcome studies on osteotomies for recurrent ligament instability are promising, but more data and long-term outcomes are needed to support early findings.