Standing frame and electrical stimulation therapies partially preserve bone strength in a rodent model of acute spinal cord injury

The aim of this study was to compare the effect of standing frame and electrical stimulation on bone quality in a rodent transection model of spinal cord injury (SCI). Seven-week-old male Wistar rats were divided into four groups: sham, n = 10; SCI, n = 7; SCI + standing frame, n = 7; and SCI + electrical stimulation, n = 7. Complete SCI was generated by surgical transection of the cord at the T10 level. Therapies were initiated 3 days after the surgery, 3 days/wk, 20 mins/day, for 30 days. Animals were killed on day 33 postinjury. No treatment preserved bone mineral density at any skeletal site tested (P = 0.08-0.99). Standing frame therapy preserved maximal load at the lumbar vertebral body (14% vs. 37% reduction, P = 0.01) and prevented SCI-induced loss of stiffness at both the femur (8% vs. 37% reduction, P = 0.03) and the tibia (35% vs. 56% reduction, P < 0.0001). Electrical stimulation therapy reduced SCI-induced loss of stiffness at the tibia only (40% vs. 56% reduction, P = 0.003). Standing frame and electrical stimulation may have potential as future therapeutic modalities to treat or prevent bone loss after SCI.