Surgical Correction of Large Talar Tilt in Varus Ankle Osteoarthritis II: A New Treatment Algorithm Based on the Tibial Plafond Inclination and Arthritis Types

Medial opening-wedge supramalleolar osteotomy (MOWSMO) is a joint-preserving surgical option for varus ankle osteoarthritis (OA); however, its ability to correct large varus talar tilt (TT), particularly in advanced diseases like Takakura stage IIIB, remains limited. Varus TT represents a complex three-dimensional deformity characterized by coronal malalignment and internal rotation, which cannot be reliably corrected by isolated supramalleolar realignment. Building on our previous work, we propose a new treatment algorithm for large varus TT based on preoperative tibial plafond inclination (TPI) and arthritis type, categorized as translational and rotational. While MOWSMO primarily addresses TPI, effective correction of talar inclination requires a balanced, multilevel approach. This includes using an oblique sliding fibular osteotomy to facilitate rotational realignment with fibular shortening and, critically, prioritizing inframalleolar correction (IMC). IMC is implemented through an "all-in-one" strategy involving lateral ligament repair, deltoid ligament release, calcaneal osteotomy, and posterior tibial tendon lengthening. Furthermore, we discuss critical intraoperative considerations, such as avoiding excessive TPI valgization to prevent a "paradoxical increase" in TT. Collectively, this framework provides clinically relevant insights and a reproducible algorithm for achieving satisfactory outcomes in the joint-preserving management of severe varus ankle OA.