Spasticity may defend skeletal muscle size and composition after incomplete spinal cord injury.
METHODS
Cross-sectional.


OBJECTIVE
(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.


METHODS
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.
Gorgey
A S
AS
Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, MI 48108, USA. agorgey@umich.edu
Dudley
G A
GA
D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D002574:Cervical Vertebrae; D003430:Cross-Sectional Studies; D006801:Humans; D008161:Lumbosacral Region; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009128:Muscle Spasticity / Q000209:etiology / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000473:pathology*; D009133:Muscular Atrophy / Q000209:etiology / Q000473:pathology; D013119:Spinal Cord Injuries / Q000150:complications / Q000473:pathology*; D013848:Thigh / Q000473:pathology