Abstract
Instrumentation surgery was applied to patients with spinal cord injury with the aim of correcting spinal deformity and assisting the patient in maintaining stability. In cases where long Harrington rods were used, however, trunk balance often became instable due to the loss of mobility of the spinal column. Using a weight balance analyzer, the sway of sitting balance was measured in L1 completely paraplegic patients fixed with Harrington rods and in those under conservative treatment. Abdominal and back muscle strength was measured using a Cybex II. In patients treated with Harrington rod, the sway of sitting balance was intense, especially during anterior movement. Dynamic sitting balance was inferior. Decreases in torque were not remarkable in isometric contraction of trunk muscles, while marked decreases were observed during isokinetic contraction. These results suggest that dynamic movement of the trunk muscles was restrained in cases fixed with Harrington rods due to stiffness of the spine, despite the fact that muscle strength was maintained.
