Myoelectric Activation Pattern Changes in the Involved Limb of Individuals With Transtibial Amputation During Locomotor State Transitions

• Published in: Archives of physical medicine and rehabilitation Vol. 98; no. 6; pp. 1180 - 1186
• Main Authors: Nakamura, Bryson H., PhD, Hahn, Michael E., PhD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.06.2017
• Subjects: Adult; Amputation; Amputation - rehabilitation; Artificial Limbs; Biomechanical Phenomena; Electromyography; Female; Gait - physiology; Humans; Locomotion; Locomotion - physiology; Lower extremity; Male; Middle Aged; Muscle, Skeletal - physiology; Physical Medicine and Rehabilitation; Physical Therapy Modalities; Rehabilitation; Walking - physiology; Statistical Parametric Mapping; BF; Gmed; biceps femoris; gluteus maximus; Lower extremity; SA; tibialis anterior; SD; SPM; Amputation; Electromyography; MG; Gmax; vastus lateralis; level ground; TA; stair descent; Locomotion; RF; VL; Rehabilitation; LG; medial gastrocnemius; rectus femoris; stair ascent; gluteus medius
• ISSN: 0003-9993; 1532-821X
• DOI: 10.1016/j.apmr.2016.12.003

Abstract Objective To investigate whether lower extremity muscle activation patterns differ in the strides leading to locomotive state transitions in the involved limb of individuals with transtibial amputation. It is hypothesized that all transitions elicit activation differences between strides as the subjects move toward the transition event. Design Single-sample, observational study. Setting University research center. Participants Volunteer sample of persons with unilateral transtibial amputation (N=9; mean age, 48.8±12.1y; mean height, 1.74±0.09m; mean weight, 86.1±24.7kg) were recruited by posting flyers in local prosthetics clinics. Interventions Not applicable. Main Outcome Measures Surface electromyography was used to measure muscle activation from 7 muscles of the involved limb. Subjects walked across 8 different terrain conditions transitioning from level-ground to ramp/stair locomotion and vice versa. Statistical Parametric Mapping analysis of variance (α<.05) was used to assess muscle activation differences in the 3 pretransition gait cycles as subjects moved toward the terrain change. Results No muscle activation changes were observed in ramp transitions. All stair transitions elicited a myoelectric difference in at least 2 muscles. The transition from stair descent to level ground elicited change in the greatest number of muscles. Tibialis anterior activation was unchanged in all transitions. Conclusions Muscle activation differences were observed in the involved limb of individuals with transtibial amputation during stair transitions, suggesting that those patterns may be successfully used in transition detection algorithms. It remains unknown whether ramp transitions can be successfully identified pretransition using electromyography.