Open and closed wedge osteotomes reduce the meniscus extrusion during walking with the knee adduction moment.

Purpose: Medial meniscus extrusion (MME) is exaggerated by mechanical loading and exhibits a significant response during gait. Open-wedge (OW) and closed-wedge (CW) high tibial osteotomy (HTO) can reduce the mechanical loading associated with MME during walking; however, the impact of the differences in these surgical procedures remains unclear. This study aimed to compare MME behaviour during walking between OWHTO and CWHTO. It was hypothesised that CWHTO would demonstrate superior outcomes compared to OWHTO in terms of reducing mechanical stress. Methods: Twenty-one knees from twenty-one patients with knee osteoarthritis were enrolled and allocated to CW and OW groups. MME during walking was evaluated using ultrasonography synchronised with three-dimensional motion analysis. The dynamic behaviour of MME was assessed by calculating the change between the MME value at initial contact and the maximum value observed during walking. Mechanical stress was evaluated using the knee adduction moment. These measurements were performed at two time points: preoperatively and postoperatively at approximately 24 months. Results: Both MME behaviour and knee adduction moment impulse values during walking were significantly reduced compared to baseline measurements MME behaviour ( Conclusions: The differences between CWHTO and OWHTO were not detected in MME behaviour during walking. Level of Evidence: Level IV.