Methods for functional assessment after C7 spinal cord hemisection in the rhesus monkey.

BACKGROUND: Reliable outcome measures are essential for preclinical modeling of spinal cord injury (SCI) in primates. MEASURES: need to be sensitive to both increases and decreases in function in order to demonstrate potential positive or negative effects of therapeutics. OBJECTIVES: To develop behavioral tests and analyses to assess recovery of function after SCI in the nonhuman primate. METHODS: In all, 24 male rhesus macaques were subjected to complete C7 lateral hemisection. The authors scored recovery of function in an open field and during hand tasks in a restraining chair. In addition, EMG analyses were performed in the open field, during hand tasks, and while animals walked on a treadmill. Both control and treated monkeys that received candidate therapeutics were included in this report to determine whether the behavioral assays were capable of detecting changes in function over a wide range of outcomes. RESULTS: The behavioral assays are shown to be sensitive to detecting a wide range of motor functional outcomes after cervical hemisection in the nonhuman primate. Population curves on recovery of function were similar across the different tasks; in general, the population recovers to about 50% of baseline performance on measures of forelimb function. CONCLUSIONS: The behavioral outcome measures that the authors developed in this preclinical nonhuman primate model of SCI can detect a broad range of motor recovery. A set of behavioral assays is an essential component of a model that will be used to test efficacies of translational candidate therapies for SCI.