Faculty Collaboration Database

Length-tension properties of ankle muscles in chronic human spinal cord injury. J Biomech 2005 Dec;38(12):2344-53

Date

10/11/2005

Pubmed ID

16214482

DOI

10.1016/j.jbiomech.2004.10.024

Scopus ID

2-s2.0-26444457277 (requires institutional sign-in at Scopus site)   28 Citations

Abstract

Contracture, or loss of range of motion (ROM) of a joint, is a common clinical problem in individuals with spinal cord injury (SCI). In order to measure the possible contribution of changes in muscle length to the loss of ankle ROM, the active force vs. angle curves for the tibialis anterior (TA) and gastrocnemiussoleus (GS) were measured in 20 participants, 10 with SCI, and 10 gender and age matched, neurologically intact (NI) individuals. Electrical stimuli were applied to the TA and GS motor nerves at incremented angles of the entire ROM of the ankle and the resulting ankle and knee torques were measured using a multi-axis load cell. The muscle forces of the TA and GS were calculated from the torque measurements using estimates of their respective moment arms and the resulting forces were plotted against joint angle. The force-angle relation for the GS at the ankle (GSA) was significantly shifted into plantar flexion in SCI subjects, compared to NI controls (t-test, p<0.001). Similar results were obtained based upon the GS knee (GSK) force-angle measurements (p<0.05). Conversely, no significant shift in the force-angle relation was found for the TA (p=0.138). Differences in the passive ROM were consistent with the force-angle changes. The ROM in the dorsiflexion direction was significantly smaller in SCI subjects compared to NI controls (p<0.05) while the plantar flexion ROM was not significantly different (p=0.114). Based upon these results, we concluded that muscle shortening is an important component of contracture in SCI.

Author List

McDonald MF, Kevin Garrison M, Schmit BD

Author

Brian Schmit PhD Professor in the Biomedical Engineering department at Marquette University

MESH terms used to index this publication - Major topics in bold

Adult
Ankle Joint
Cervical Vertebrae
Computer Simulation
Contracture
Electric Stimulation
Female
Humans
Male
Middle Aged
Models, Biological
Muscle Contraction
Muscle, Skeletal
Range of Motion, Articular
Spinal Cord Injuries
Stress, Mechanical
Thoracic Vertebrae
Torque