Custom Ankle-Foot Orthosis in Foot Drop: Influence on Body Joints Kinematics

Ankle Foot Orthoses (AFOs) are external supports typically prescribed in clinical practice to address foot drop deficits. Lower limb orthoses have been shown to have positive effects on spatio-temporal gait metrics, while the impact on body joint kinematics is less clear and varies in the literature. The objective of this study is to investigate the presence of a common movement pattern in body joints that compensates for the foot drop deficit. The study focuses on the trunk, knee, and hip joints. Eight patients with unilateral foot drop participated in walking trials on an instrumented treadmill. The trials included testing with both a conventional and a 3D printed custom passive AFO. The study results indicate that the use of AFOs on the impaired foot did not have a significant effect on joint kinematics in the study population, except for an improvement in trunk anterior flexion provided by the custom orthosis. There is evidence of altered biomechanics that cannot be corrected by passive orthoses alone. The study highlights the importance of physical training and long-term re-education of the patient in the correct use of the orthosis.