Kinematic features of rear-foot motion using anterior and posterior ankle-foot orthoses in stroke patients with hemiplegic gait

Abstract

Objective: To evaluate the kinematic features of rear-foot motion during gait in hemiplegic stroke patients, using anterior ankle-foot orthoses (AFOs), posterior AFOs, and no orthotic assistance.

Design: Crossover design with randomization for the interventions.

Setting: A rehabilitation center for adults with neurologic disorders.

Participants: Patients with hemiplegia due to stroke (n=14) and able-bodied subjects (n=11).

Interventions: Subjects with hemiplegia were measured walking under 3 conditions with randomized sequences: (1) with an anterior AFO, (2) with a posterior AFO, and (3) without an AFO. Control subjects were measured walking without an AFO to provide a normative reference.

Main outcome measures: Rear-foot kinematic change in the sagittal, coronal, and transverse planes.

Results: In the sagittal plane, compared with walking with an anterior AFO or without an AFO, the posterior AFO significantly decreased plantar flexion to neutral at initial heel contact (P=.001) and the swing phase (P<.001), and increased dorsiflexion at the stance phase (P=.002). In the coronal plane, the anterior AFO significantly increased maximal eversion to neutral (less inversion) at the stance phase (P=.025), and decreased the maximal inversion angle at the swing phase when compared with using no AFO (P=.005). The posterior AFO also decreased the maximal inversion angle at the swing phase as compared with no AFO (P=.005). In the transverse plane, when compared with walking without an AFO, the anterior AFO and posterior AFO decreased the adduction angle significantly at initial heel contact (P=.004).

Conclusions: For poststroke hemiplegic gait, the posterior AFO is better than the anterior AFO in enhancing rear-foot dorsiflexion during a whole gait cycle. The anterior AFO decreases rear-foot inversion in both the stance and swing phases, and the posterior AFO decreases the rear-foot inversion in the swing phase when compared with using no AFO.