Introduction: Spinal cord injury (SCI) is a serious clinical disorder, which involves the patient’s family as well as the community. After sever SCI, astrocytes of the central nervous system become reactive astrocytes, and produce glial scar which is a major obstacle to axons regeneration in the spinal cord. However, some studies have confirmed a spontaneous partial locomotor recovery in injured animals in the course of time and without any therapeutic interventions. Thus, in this study, locomotor function of animals with SCI was assessed to determine the exact scope of such a recovery through BBB (Basso, Bresnahan and Beattie) locomotor test during 20 weeks.
 
Materials and Methods: In this research, 18 adult male Wistar rats were used and randomly divided into 3equale groups: the  normal control, the sham, the injured. Animals in the normal control group did not received any intervention, but for the sham and injured groups, laminectomy and contusion model in segment T10 of spinal cord were accomplished, respectively. Locomotor improvement of animals in all the groups was evaluated for 20 weeks.
 
Findings: According to our investigation, comparison of the results of locomotor assessment of the second week against that of the 20th week of the spinal cord injured group without treatment demonstrated  a partial locomotor recovery, since the BBB score of lesion in these animals was 1.4 in the second week and reached up to 16 in the Twentieth week.
 
Discussion & Conclusion: Our Results showed that spontaneous locomotor recovery in animals with spinal cord defects increases after 20 weeks (from 16 21 score) in the course of  time and without any therapeutic interventions.