Introduction: Preclinical studies indicate that 36 minutes following TSCI there is MRI evidence of secondary injury and spinal cord swelling. In patients with AIS grades A-B, swelling expands at a rate of 900 micrometers/hour, culminating in an intramedullary lesion (IML) which measures ~50 mm at 3 days post-injury. We performed a retrospective analysis to measure the effect of IML length on long-term AIS grade conversion.

Methods: METHODS: Ninety-five adult patients who underwent decompressive surgery for cervical TSCI were included. Post-decompression IML length was measured and long-term AIS grades were recorded. Analysis was conducted by logistic regression.

Results: RESULTS: AIS grade was A in 51, B in 26, and C in 18 patients. Decompression was completed within a mean of 18.2 hours. Mean IML length on postoperative MRI imaging was 72.6 mm. AIS grade conversion was noted in 46 (48.4%) patients. Conversion was noted in 27.5% of AIS grade A, 65.4% of AIS grade B and 83.3% of AIS grade C patients. Timing of decompression had no effect on AIS grade conversion, but conversion was significant in older patients, those with higher ASIA motor score, lower injury severity score, shorter IML length and better evidence of decompression on postoperative MRI. Regression analysis indicated a significant relationship between AIS grade conversion and IML length on postoperative MRI (OR 0.953, 95% CI=0.9313-0.9761, P=0.001).

Conclusions: : In AIS grades A-C cervical TSCI, post-decompression rostrocaudal IML length was a significant predictor of AIS grade conversion.

Patient Care: Neurosurgeons pay especial attention to the MRI signal changes before decompression of the spinal cord in traumatic spine and spinal cord injury

Learning Objectives: The participants will learn about the significant variables influencial in neurological recovery following spinal cord decompression in traumatic fracture dislocations of the cervical spine associated with significant spinal cord injury.

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