Design and Validation of a Real-Time Visual Feedback System to Improve Minimum Toe Clearance (mTC) in Transfemoral Amputees

Abstract

Tripping is accompanied by reduced minimum toe clearance (mTC) during the swing phase of gait. The risk of fall due to tripping among transfemoral amputees is nearly 67% which is greater than the transtibial amputees. Therefore, intervention to improve mTC can potentially enhance the quality of life among transfemoral amputees. In this paper, we first develop a real-time visual feedback system with center of pressure (CoP) information. Next, we recruited six able-bodied and three transfemoral amputees to investigate the effect on mTC while participants were trained to shift the CoP anteriorly/posteriorly during heel strike. Finally, to assess the lasting effect of training on mTC, retention trials were conducted without feedback. During feedback, posterior shift in the CoP improved the mTC significantly from 4.68±0.40cm to 6.12±0.68cm (p<0.025) in able-bodied participants. A similar significant improvement in mTC from 4.60±0.55cm to 5.62±0.57cm was observed in amputees during posterior shift of CoP. Besides mTC, maximal toe clearances, i.e., maxTC1 and maxTC2, also showed a significant increase (p<0.025) during the posterior shift of CoP in both the participants. Moreover, during retention, mTC did not differ significantly (p>0.05) from feedback condition in amputee, suggesting a positive effect of feedback training. The foot-to-ground angle (FGA) at mTC increased significantly (P<0.025) during posterior shift feedback in able-bodied suggests active ankle dorsiflexion in increasing mTC. However, in amputees, FGA at mTC did not differ significantly during both anterior and posterior CoP shift feedback. The present findings suggest CoP feedback as a potential strategy during gait rehabilitation of transfemoral amputees.

Wearable Haptic Feedback System for Training Propulsion Force in Individuals with Solid Ankle Foot Orthosis: Development and Validation

“…The studies which seem consistent with the current hypothesis suggest that the step/stride length (synchronous to the CoM and CoP separation) modulation alters the GRFAP [47], [49]. Our previous studies [50], [51] on the amputee population suggested that the relative separation between the CoM and CoP provides the momentum to the swinging limb increasing the swing limb joint angles and the toe clearance. However, the GRFAP was not investigated but it was believed the increment in the swing leg energetics was because of the enhancement in the underlying propulsion force with the displacement in the center of pressure.…”

Effect of a Kinematic Gait Parameter-Based Haptic Cue on Toe Clearance in Parkinson's Patients

“…FSA is an important biomechanical parameter to target among PD patients as it is correlated with many gait performance parameters. Interestingly, the proposed method addresses the future goal of the previous studies [13], [41]. The limitation of the current study is the shorter training time which can be increased in the future to see the actual effects of the cueing.…”

Technology-based therapy-response evaluation of axial motor symptoms under daily drug regimen of patients with Parkinson’s disease

“…Accordingly, rehabilitation therapy, as a complementary treatment to antiparkinsonian drugs, those approaches that focus on increasing toe-ground clearance should be the preferred option. These rehabilitation programs include, for example, an attentional strategy emphasizing heel strike (Ginis et al, 2017) and biofeedback gait training measures (Nagano et al, 2020;Tiwari and Joshi, 2021).…”