Results of Medial Open Wedge High Tibial Osteotomy With 5 Years Follow-Up: A Prospective Multicenter Cohort Study

Abstract

Aim: The purpose was to assess whether open wedge high tibial osteotomy (OWHTO) achieves good functional and radiological results until 5 years follow-up.

Materials and Methods: A prospective multicenter study in 118 patients 40 years of age and older with osteoarthritis (OA) or osteonecrosis evaluated the outcome after OWHTO using locking plate fixation (TomoFix Medial High Tibial Plate (MHT)® small plate: Synthes GmbH, Oberdorf, Switzerland). This paper discusses patient-reported and functional outcomes, radiological results and adverse events after 5 years follow-up. Adverse events (AEs) were evaluated by a complication review board and classified according to a standard classification system, and radiographs were analyzed by study-independent surgeons.

Results: Significant improvement from baseline was observed in the Knee Injury and Osteoarthritis Outcome Score (KOOS), Oxford Knee Score (OKS), Japanese Orthopaedic Association knee score, range of motion, and SF-36 Physical Component Summary (PCS). The anatomical alignment achieved after the OWHTO remained stable over the 5-year follow-up period. The radiologically assessed status of OA (Kellgren-Lawrence) and joint space width narrowing progressed significantly between baseline and five years. The estimated risk of developing at least one local postoperative implant/surgery, bone, or soft tissue AE was 5.1% (95%CI: 1.9; 10.7), 15.3% (95% CI: 9.3; 23.0), and 12.7% (95%CI: 7.3; 20.1), respectively.

Conclusion: Function, pain and quality of life can improve during the period of five years despite a structural progression of OA in patients after medial OWHTO.