[Experimental studies on acute spinal cord injury].

Treatment of acute spinal cord injury has not been yet established. The purpose of this study was to investigate the effect of posterior median longitudinal myelotomy on early stage and the administration of Mannitol on experimental spinal cord injury. The spinal cord of adult's dogs was traumatized by the weight dropping method at the level of T 10. On the pathological findings of the traumatized cord, the secondary changes such as edema and hemorrhagic necrosis were shown early within a few hours. All experimental dogs injured by 500 gm-cm force were resulting in paraplegia one month after trauma if no treatment given. Eight out of nine dogs treated with myelotomy one hour after trauma, could walk with swaying their waist one month after operation. The dogs treated by myelotomy four hours after trauma could stand or raise their hips, but none could walk or run. The dogs given Mannitol 30 minutes and four hours after trauma showed similar results as the group treated with myelotomy four hours after trauma. These results suggest that secondary spinal autodestruction following primary cord contusion starts early after trauma beyond expectations and the myelotomy on super early stage can protect these secondary irreversible cord damage. Moreover the administration of Mannitol can protect temporally these cord damage too. Therefore, the combination therapy of Mannitol administration and the following performed myelotomy can give the same effect as super early myelotomy.