Forelimb locomotor rating scale for behavioral assessment of recovery after unilateral cervical spinal cord injury in rats.
BACKGROUND
Cervical spinal cord injury (SCI) models in rats have become increasingly useful because of their translational potential. The goal of this study was to design, develop and validate a quick and reliable forelimb locomotor rating scale for adult rats with unilateral cervical SCI injury.


METHODS
Adult female rats were subjected to a C5 unilateral mild contusion (n=10), moderate contusion (n=10) or hemisection injury (n=9). Forelimb locomotion was evaluated before injury, four times during the first week (Days 2, 3, 4 and 7) and weekly for up to 8 weeks post-injury. Scoring categories were identified and animals were ranked based on their performance in these categories. The scale was validated for its usefulness by comparing animals with different injury models (dorsolateral funiculotomy C3/4), levels of injury (moderate contusion C4) and sex (male - moderate contusion C3/4) and also by correlating FLS scores with other established behavioral tests (grid walking and kinetic tests).


RESULTS
Forelimb performance on both the grid-walking and kinetic tests was positively correlated with the forelimb locomotor rating scale (FLS). Histological analysis established a positive correlation between the spared tissue and the observed FLS score. Our results show that the new rating scale can reliably detect forelimb deficits and recovery predicted by other behavioral tests. Furthermore, the new method provides reproducible data between trained and naïve examiners.


CONCLUSIONS
In summary, the proposed rating scale is a useful tool for assessment of injury and treatments designed to enhance recovery after unilateral cervical SCI.
University of Delaware, Newark, DE, United States. Electronic address: anitausingh@hotmail.com.
Anita
A
Singh
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States; Thomas Jefferson University, Philadelphia, PA, United States.
Laura
L
Krisa
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States.
Kelly L
KL
Frederick
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States.
Harra
H
Sandrow-Feinberg
Drexel University, Philadelphia, PA, United States.
Sriram
S
Balasubramanian
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States.
Scott K
SK
Stackhouse
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States.
Marion
M
Murray
Drexel University, College of Medicine, Queen Lane, Philadelphia, PA, United States.
Jed S
JS
Shumsky
D000818:Animals; D002574:Cervical Vertebrae; D004185:Disability Evaluation; D004195:Disease Models, Animal; D005260:Female; D005552:Forelimb; D007839:Functional Laterality; D009043:Motor Activity; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012737:Sex Factors; D013116:Spinal Cord / Q000473:pathology; D013119:Spinal Cord Injuries / Q000175:diagnosis* / Q000473:pathology; D013997:Time Factors
Behavioral test; Forelimb; Locomotion; Rat; Recovery of function; Spinal cord injury