The effect of early therapeutic electrical stimulation on bone mineral density in the paralyzed limbs of the rabbit

The purpose of this animal experiment was to evaluate the changes of bone m ineral density in paralyzed limbs, and to assess the effects of electricall y stimulating muscle contraction upon bone mineral density (BMD) in paralyz ed limbs during the four week period immediately following spinal cord inju ry (SCI). Ten rabbits were used for the study, spinal cords were totally transected a t the T11 spine level. The paralyzed quadriceps femoris of one limb was con tracted by electrical stimulation for 60-minutes daily, while the other sid e was not stimulated as a control. The BMD of each lower limb was: measured by Dual Photon Absorptiometry before and four weeks after acute SCI. BMD o f both limbs decreased in all rabbits four weeks after SCI. The decrease in BMD for stimulated and non-stimulated limbs was 6.130 +/- 3.212% and 9.098 +/- 3.831%, respectively during the four-week period after SCI. The BMD of stimulated limbs decreased significantly less than that of the non-stimula ted limbs. Electrically induced muscular contraction reduced bone mineral l oss in the paralyzed limb during the early stage of SCI in the rabbit.