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Updated: Jul 13, 2026

Paradigms of Lower Extremity Electrical Stimulation Training After Spinal Cord Injury
Published on: February 1, 2018
Spasticity may defend skeletal muscle size and composition after incomplete spinal cord injury
1Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, MI 48108, USA. agorgey@umich.edu
Design:
Cross-sectional.
Objectives:
(1) To determine the effects of the level of spinal cord injury (SCI) on skeletal muscle, intramuscular fat (IMF) cross-sectional areas (CSAs) and relative IMF; (2) to determine the relation, if any, of spasticity to each of these variables after incomplete SCI.
Settings:
In-patient study at the Shepherd Center, Atlanta, GA, USA.
Methods:
Thirteen individuals with incomplete SCI were classified according to their level of injury into a high level of injury group (HLI, C5-C7, n=8) and a low level of injury group (LLI, T12-L2, n=5). Spasticity was determined for thigh muscles using a modified Ashworth scale at 6 weeks post-injury. T1-weighted magnetic resonance (MR) images were taken 6 weeks post-injury to measure thigh skeletal muscle and IMF CSAs.
Results:
Spasticity was significantly evident in the HLI group compared to the LLI group (P=0.023). Six weeks post-injury, muscle CSA was 103+/-18 cm(2) in the HLI group and 80+/-20 cm(2) in the LLI group (P=0.042). Relative IMF was 3.6+/-2.0% in HLI and 7.5+/-4.0% in LLI (P=0.021). Additionally, spasticity accounted for 54% of the variability in muscle CSA for all subjects (r (2)=0.54, P=0.006).
Conclusions:
Spasticity may be an important factor in defending skeletal muscle size and indirectly preventing IMF accumulation early after incomplete SCI.
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