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

ABSTRACT

The purpose of this animal experiment was to evaluate the changes of bone mineral density in paralyzed limbs, and to assess the effects of electrically stimulating muscle contraction upon bone mineral density (BMD) in paralyzed limbs during the four week period immediately following spinal cord injury (SCI). Ten rabbits were used for the study, spinal cords were totally transected at the T11 spine level. The paralyzed quadriceps femoris of one limb was contracted by electrical stimulation for 60-minutes daily, while the other side 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 of 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-stimulated limbs. Electrically induced muscular contraction reduced bone mineral loss in the paralyzed limb during the early stage of SCI in the rabbit.