Functional and Radiological Outcomes of High Tibial Osteotomy Using the Hemicallotosis Method by Dynamic Axial...

Medial compartment osteoarthritis (MCOA) of the knee is a major cause of pain and disability, often associated with varus malalignment. In younger and active patients, high tibial osteotomy (HTO) helps realign the mechanical axis, offloading the diseased medial compartment and delaying the need for arthroplasty. The hemicallotasis technique using a dynamic axial fixator (DAF) offers gradual correction with minimal soft-tissue damage and no internal hardware. This study evaluated the functional and radiological outcomes of HTO using the hemicallotasis method with DAF in patients with MCOA and varus deformity. This longitudinal descriptive study was conducted at a tertiary care teaching hospital from 2021 to 2024. Thirty-seven patients with isolated MCOA and varus deformity underwent medial opening wedge HTO using the hemicallotasis method under image guidance. Those with inflammatory, bicompartmental, or tricompartmental arthritis, or previous fractures around the knee, were excluded. Functional assessment was done using the Oxford Knee Score (OKS) at one, three, and six months postoperatively. Radiological outcomes were evaluated by measuring mechanical axis deviation (MAD). The mean OKS showed progressive improvement, indicating steady functional recovery. Younger patients demonstrated slightly higher baseline and postoperative scores. A strong positive correlation was observed between mechanical alignment correction and functional gain. HTO using the hemicallotasis method with a DAF is an effective, joint-preserving procedure for MCOA with varus deformity. It provides accurate alignment correction, excellent functional improvement, and a low complication rate. This technique offers a valuable option for younger and active patients, maintaining joint function while delaying the need for knee arthroplasty.