ENHANCEMENT OF FUNCTIONAL RECOVERY FOLLOWING A CRUSH LESION TO THE RAT SCIATIC-NERVE BY EXPOSURE TO PULSED ELECTROMAGNETIC-FIELDS

Previous studies showed that exposure to pulsed electromagnetic fields (PEMF) produced a 22% increase in the axonal regeneration rate during the first 6 days after crush injury in the rat sciatic nerve. We used the same injury model to assess the effect on functional recovery. Th e animals were treated with whole body exposure to PEMF (0.3 mT, repet ition rate 2 Hz) for 4 h/day during Days 1-5 while held in plastic res trainers. Functional recovery was serially assessed up to Postinjury D ay 43 using recently described video imaging of the 1-5 toe spread and the gait-stance duration. Footprint analysis was also used with calcu lation of a sciatic function index. Those animals treated with PEMF ha d improved functional recovery, as compared to sham controls, using th e tests for video 1-5 toe spread and gait-stance duration (P = 0.001 a nd P = 0.081, respectively). This effect was found throughout the 43-d ay recovery period. No effect was found using the sciatic function ind ex. This study confirms that functional recovery after nerve crush les ion is accelerated by PEMF and has broad implications for the clinical use of these fields in the management of nerve injuries. (C) 1994 Aca demic Press, Inc.