An experimental study on spinal cord traction effect.

An experimental study was carried out on the pathophysiology of spinal cord traction injury. In 50 dogs, spinal cord traction impairment was created by gradual lumbosacral cord traction. Physiologic integrity of the spinal cord was monitored and recorded by the spinal evoked potentials. With greater traction force, the potentials gradually lessened in amplitude. The vulnerability of the spinal cord to compression force was increased by spinal cord traction. Under 200 g traction, the vulnerability of the lower thoracic cord was most increased. The authors conclude that tethered cord syndrome is caused by the impairment of the spinal cord and lumbosacral roots due to traction, and that spinal cord traction not only causes spinal cord impairment but increases the spinal cord vulnerability to compression.