Adaptation of the Basso-Beattie-Bresnahan locomotor rating scale for use in a clinical model of spinal cord injury in dogs.

BACKGROUND: Naturally occurring acute spinal cord injury (SCI) in pet dogs provides an important clinical animal model through which to confirm and extend findings from rodent studies; however, validated quantitative outcome measures for dogs are limited.

NEW METHOD: We adapted the Basso Beattie Bresnahan (BBB) scale for use in a clinical dog model of acute thoracolumbar SCI. Based on observation of normal dogs, modifications were made to account for species differences in locomotion. Assessments of paw and tail position, and trunk stability were modified to produce a 19 point scale suitable for use in dogs, termed the canine BBB scale (cBBB). Pet dogs with naturally occurring acute SCI were assigned cBBB scores at 3, 10 and 30days after laminectomy.

RESULTS: Scores assigned via the cBBB were stable across testing sessions in normal dogs but increased significantly between days 3 and 30 in SCI-affected dogs (p=0.0003). The scale was highly responsive to changes in locomotor recovery over a 30day period, with a standardized response mean of 1.34.

COMPARISON WITH EXISTING METHODS: Concurrent validity was good, with strong correlations observed between the cBBB and two other locomotor scales, the OSCIS (r=0.94; p<0.001) and the MFS (r=0.85; p<0.0001). cBBB scores inversely correlated with other assessments of recovery including mechanical sensory threshold (r=-0.68; p<0.0001) and coefficient of variation of stride length (r=-0.49; p<0.0001).

CONCLUSIONS: These results support the use of the cBBB to assess locomotor recovery in canine clinical translational models of SCI.