Spinal Cord Injury & Repair

Behavioural Assessments

BBB Scoring is used to assess the motor function of rats.

Post-injury motor behavior is assessed via the Basso, Beattie and Bresnahan (BBB) locomotor scale method [1,2]. The BBB score is used for function recovery and locomotors testing in chronic SCI study. The scale (0 - 21) represents sequential recovery stages and categorizes combinations of rat joint movement, hindlimb movements, stepping, forelimb and hindlimb coordination, trunk position and stability, paw placement and tail position.

Each rat is then assigned to one of three categories, depending on their score:

  1. Early Stage (score of 0 - 7): Composed of isolated joint movements with little or no hindlimb movement
  2. Intermediate Stage (score of 8 - 13): Intervals of uncoordinated stepping
  3. Late Stage (score of 14 - 21): Forelimb and hindlimb coordination

Due to a naturally recovering reflex in rats, even spinal cord injured rats regain their ability to walk within the weeks following injury. The hindlimbs are able to generate a spinal reflex arc that allows hindlimb stepping without the use of the brain. For this reason, data collected from SCI rats generally improves for the first few weeks, then plateaus at some value, which is indicative of the extent of permenant damage.

BBB Scores for hypothermia treated rats [3]
BBB Scores for midline versus unilateral injured rats [4]


  1. Basso, D, Beattie, M, and Bresnahan, J, A sensitive and reliable locomotor rating scale for open field testing in rats. J Neurotrauma, 1995. 12(1): p. 1-21.
  2. Basso, D, Beattie, M, and Bresnahan, J, Graded Histological and Locomotor Outcomes after Spinal Cord Contusion Using the NYU Weight-Drop Device versus Transection. Experimental Neurology, 1996. 139(2): p. 244-256.
  3. A. Maybhate, C. Hu, F. A. Bazley, Q. Yu, N. V. Thakor, C. Kerr, and A. All, "Potential Long Term Benefits of Acute Hypothermia after Spinal Cord Injury: Assessments with Somatosensory Evoked Potentials", Accepted for publication in Critical Care Medicine, July 2011
  4. Faith A. Bazley, Charles Hu, Anil Maybhate, Amir Pourmorteza, Nikta Pashai, Nitish V. Thakor, Candace Kerr, Angelo H. All. "Electrophysiologal evaluation of sensory and motor pathways after incomplete unilateral spinal cord contusion." Submitted to Journal of Neurosurgery: Spine.