pictorial and systematic approach to varus deformity

Background: Varus deformity is the most prevalent malalignment in total knee arthroplasty (TKA), ranging from mild, passively correctable cases to recalcitrant deformities. Traditional correction often involves extensive soft tissue release, yet controversy remains regarding the optimal sequence and necessity of releasing the superficial medial collateral ligament (MCL).

Objective: This article describes a systematic approach to achieving coronal alignment and gap balancing in varus TKA without superficial MCL release, utilizing computer navigation and specific osteotomy techniques.

Key Points: The methodology is based on the premise that the superficial MCL is often tented by osteophytes rather than contracted. Preoperative and intraoperative assessments must identify extra-articular deformities (EAD) and hindfoot valgus, which influence the weight-bearing axis. Following bone resections perpendicular to the mechanical axes, three clinical scenarios guide soft tissue management. Symmetrical gaps require no further release. If the extension gap is tight medially but the flexion gap is symmetrical, a posteromedial capsular release or a sliding medial condylar osteotomy is indicated. If both gaps are tight medially, a reduction osteotomy of the posteromedial tibial flare is performed, followed by semimembranosus release or corrective metaphyseal osteotomy if EAD is present.

Conclusion: Precise alignment and ligamentous balance in severe varus deformity can be achieved by addressing bone morphology and posteromedial structures. This systematic protocol prioritizes preservation of the superficial MCL and utilizes intra-articular or extra-articular osteotomies to manage complex deformities without requiring constrained implants.