MUSCLE ATROPHY IS PREVENTED IN PATIENTS WITH ACUTE SPINAL-CORD INJURYUSING FUNCTIONAL ELECTRICAL-STIMULATION

Severe muscle atrophy occurs rapidly following traumatic spinal cord i njury (SCI). Previous research shows that neuromuscular or 'functional ' electrical stimulation (FES), particularly FES-cycle ergometry (FES- CE) can cause muscle hypertrophy in individuals with chronic SCI (>1 y ear post-injury). However, the modest degree of hypertrophy in these a lready atrophied muscles has lessened earlier hopes that FES therapy w ould reduce secondary impairments of SCI. It is not known whether FES treatments are effective when used to prevent, rather than reverse, mu scle atrophy in individuals with acute SCI. This study explored whethe r unloaded isometric FES contractions (FES-IC) or FES-CE decreased sub sequent muscle atrophy in individual with acute SCI (<3 months post-in jury). Twenty-six subjects, 14-15 weeks posttraumatic SCI, were assign ed to control, FES-IC, or FES-CE against progessively increasing resis tance. Subjects were involved in the study for 3 or 6 months. Total bo dy lean body mass (TB-LBM), lower limb lean body mass (LL-LBM), and gl uteal lean body mass (G-LBM) were determined before the study, and at 3 and 6 months using dual energy X-ray absorptiometry (DEXA). Controls lost an average of 6.1%, 10.1%, 12.4%. after 3 months and 9.5%, 21.4% , 26.8% after 6 months in TB-LBM. LL-LBM and G-LBM respectively. Subje cts in the FES-IC group consistently lost less lean body mass than con trols, however, only 6 month G-LBM loss was significantly attenuated i n this group relative to the controls. In the FES-CE group, LL-LBM and G-LBM loss were prevented at both 3 and 6 months, and TB-LBM loss was prevented at 6 months. In addition, FES-CE significantly increased G- LBM and LL-LBM after 6 months of training relative to pre-training lev els. Within the control group, there was no significant relationship b etween LL-LBM loss (3 and 6 months) and the number of days between inj ury and baseline measurement. In summary, this study shows that FES-CE , but not FES-IC, training prevents muscle atrophy in acute SCI after 3 months of training, and causes significant hypertrophy after 6 month s. The magnitude of differences in regionalized LBM between controls a nd FES-CE subject raises hopes that such treatment may indeed be benef icial in preventing secondary impairments of SCI if employed before ex tensive post-injury atrophy occurs.