Pin sensation as a predictor of extensor carpi radialis recovery in spinal cord injury.

The purpose of this prospective study was to determine if initial preservation of C5 pin sensation could predict extensor carpi radialis (ECR) motor recovery in the zone of partial preservation after spinal cord injury (SCI). The study compared initial C5 pin sensation and initial ECR strength as predictors of ECR motor recovery after C4 and C5 SCI. The initial motor and sensory evaluation was done less than seven days after injury. Motor power was graded from absent (0/5) to normal strength (5/5). Pin sensation was graded as absent (0/2) decreased (1/2) or normal (2/2). The manual muscle test was performed weekly to four weeks and than at three, six, and 12 months after injury. An ECR muscle grade of > or = 3/5 was defined as recovery. C5 pin sensation at the lateral antecubital fossa significantly correlated with ECR recovery to > or = 3/5 (p < 0.001). Only two of nine subjects with absent C5 pin sensation recovered ECR to > or = 3/5, whereas 14 of 15 subjects with 1/2 or 2/2 C5 pin sensation had ECR motor recovery to > or = 3/5. All ten subjects with 1/5 or 2/5 initial ECR strength had ECR motor recovery. Five of six subjects with 0/5 initial ECR strength and subsequent ECR recovery to > or = 3/5 were found to have C5 pin preservation. In conclusion the presence of 1/5 to 2/5 initial ECR strength or 1/2 or 2/2 C5 pin sensation were highly significant predictors of ECR motor recovery to > or = 3/5 in C4 and C5 motor complete quadriplegic subjects.(ABSTRACT TRUNCATED AT 250 WORDS)