Development of muscle tone and electromygraphic patterns after muscle-tendon surgery in children with spastic diplegia

Abstract

comparison to exercise on a treadmill, and what other training parameters can influence it. Patients/materials andmethods: Ten CP children, GMFCS level 2 or 3, attended identical training/diagnostic sessions on a robotic driven gait orthosis (DGO) Lokomat (Hocoma). Examination was conducted after a 15-min training on DGO, during which both comfortable and maximum speed were determined. Next an EMG activity assessmentwas conducted during training on the DGO and on a treadmill with a bodyweight-support Levi system. The examination was conducted at comfortable and maximum speeds, with 50% and 100% leading force,with 30% bodyweight-support orwithout it. Sagittal video recordings of gait were made, together with simultaneous surface electromyography recordings of the rectus femoris m. (RF), semitendinosis m. (ST) using the ME6000 system with Megawin software (Mega Electronics Ltd). Eight trials were conducted on theDGOand four on a treadmill in different combinations of bodyweight-support and leading force. In order to calculate average levels of EMG, SD, min., max., surface and median, in each of the trials 20 stepswere taken from a 30 s recording and averaged with RMS. Results: A significant (p<0.05) increase EMG activity was observed during training on a treadmill in comparison to that on the Lokomat in all of the trials. Moreover, increase of average EMG levels was also observed with smaller bodyweight-support and leading force. Discussion and conclusions: These preliminary results show, that the Lokomat changesmuscle activity in comparison towalking on a treadmill more than just using bodyweight-support. Lower levels of muscle activation and less physical effort allow for long trainingswith CP children, GMFCS levels II, III and even IV forwhom the possibilities of gait improvement are greatly limited. This is probably a factor influencing the treatment.