Year, Volume, Issue, Page(s):07, 45, 4, 304-9
Study design: Cross-sectional and longitudinal design. Objectives: (1) To quantify skeletal muscle cross-sectional area (CSA) after correcting for intramuscular fat (IMF) in thigh muscle groups 6 weeks after incomplete spinal cord injury (SCI), (2) to monitor the changes in muscle CSA and IMF after 3 months from the initial measurement. Setting: Academic institution Athens, GA, USA. Methods: Six incomplete SCI patients (2874 years, 17875 cm and 7876 kg, mean7SE, C7 to L3, American Spinal Injury Association B or C) were tested at 571 weeks and 3 months after the initial measurement. T1-weighted magnetic resonance images were taken of both thighs. Six able-bodied (AB) controls were matched in age, sex, height and weight (2974 years, four male and two female subjets, 17975 cm and 7776 kg). Results: At 6 weeks post-injury, muscle CSA was 8274 cm2 in incomplete SCI and 123721 cm2 in AB controls (P¼0.04). IMF CSA was 5.271.3 and 2.370.6 cm2 in incomplete SCI and AB controls, respectively (P¼0.03). Relative IMF was three-fold higher (P¼0.03) in the SCI group versus AB controls (5.871.4 versus 2.070.6%). After 3 months, IMF increased 26% in the SCI group compared to the initial measurement (P¼0.02). Conclusions: Skeletal muscle atrophy is associated with greater IMF accumulation in SCI group 6 weeks post-injury compared to AB controls. Moreover, IMF continues to increase over time in incomplete SCI.