Evaluating the Effect of Modified Ankle Foot Orthosis on Knee Adduction Moment and Spatiotemporal Parameters in Subjects With Medial Compartment Osteoarthritis of the Knee Joint: A Pilot Study Publisher



Mahmoodi M ; Arazpour M ; Mousavi ME
Source: Journal of Prosthetics and Orthotics Published:2026

Abstract

ABSTRACT – Introduction – The aim of this study was to develop a modified ankle-foot orthosis (AFO) with a lateral wedge beneath the sole, and to investigate its effect on the knee adduction moment in people with medial knee osteoarthritis (MKOA). Method – In this pilot study, the effects of modified AFO were evaluated in five individuals diagnosed with MKOA by a specialist. Those who met the inclusion criteria had their gait parameters were analyzed before and after using the AFO in laboratory setting. The parameters measured included the adductor moment applied to the knee, hip, ankle, as well as each individual’s walking speed, both before and immediately after using the orthoses. Result – The result indicates that there was no statistically significant difference in the temporal-spatial parameters, as well as the hip, knee and ankle moments, between individuals without the AFO and those with it (P > 0.05). However, a significant decrease was observed in the knee frontal plane moments with the use of the orthosis, along with a significant reduction in the ankle flexion moment after using the AFO. Conclusions – In this pilot study, the results showed that the use of the modified AFO significantly reduced the external adduction moment at the knee. This reduction may contribute to notable improvements in functional gait, potentially slowing disease progression and alleviating pain in the individuals with MKOA. Further investigation is warranted over a longer duration, incorporating clinical parameters to validate these findings. Clinical Relevance – The adduction moment is a critical parameter that exerts stress on the medial compartment of the knee joint. This study provides some data that AFOs are effective in reducing knee adduction moment. Consequently, the use of AFO serves as an effective component of conservative treatment for people with MKOA. © 2026 Lippincott Williams & Wilkins