Kinematic Study of Locomotor Recovery after Spinal Cord Clip Compression Injury in Rats

Abstract

After spinal cord injury (SCI), precise assessment of motor recovery is essential to evaluate the outcome of new therapeutic approaches. Very little is known on the recovery of kinematic parameters after clinically-relevant severe compressive/contusive incomplete spinal cord lesions in experimental animal models. In the present study we evaluated the time-course of kinematic parameters during a 6-week period in rats walking on a treadmill after a severe thoracic clip compression SCI. The effect of daily treadmill training was also assessed. During the recovery period, a significant amount of spontaneous locomotor recovery occurred in 80% of the rats with a return of well-defined locomotor hindlimb pattern, regular plantar stepping, toe clearance and homologous hindlimb coupling. However, substantial residual abnormalities persisted up to 6 weeks after SCI including postural deficits, a bias of the hindlimb locomotor cycle toward the back of the animals with overextension at the swing/stance transition, loss of lateral balance and impairment of weight bearing. Although rats never recovered the antero-posterior (i.e. homolateral) coupling, different levels of decoupling between the fore and hindlimbs were measured. We also showed that treadmill training increased the swing duration variability during locomotion suggesting an activity-dependent compensatory mechanism of the motor control system. However, no effect of training was observed on the main locomotor parameters probably due to a ceiling effect of self-training in the cage. These findings constitute a kinematic baseline of locomotor recovery after clinically relevant SCI in rats and should be taken into account when evaluating various therapeutic strategies aimed at improving locomotor function.

Diffusion Tensor Imaging as a Predictor of Locomotor Function after Experimental Spinal Cord Injury and Recovery

“…These findings are comparable to those made by Basso and colleagues 36 in their original description of the BBB scale. Similarly, the current study's evaluations of hindlimb kinematics were similar to those of Couto and associates 50 after experimental mild SCI contusion as well as Alluin and coworkers 51 after spinal cord clip compression. The ability to recover and/or preserve weight-bearing has significant clinical implications for patients with SCI by reducing associated comorbidities such as pulmonary infections and skin breakdown.…”

Delayed Intervention with Intermittent Hypoxia and Task Training Improves Forelimb Function in a Rat Model of Cervical Spinal Injury

“…Treadmill training in rodents after SCI is commonly used to investigate the role of repetitive movement training (e.g., spinal learning) with moderate to severe paralysis, or to investigate the contribution of physical exercise on recovery in animals able to walk with weight-supported steps. 16,19,[28][29][30][31][32][33] In the lesion model studied here, 1 week of daily treadmill training beginning 4 weeks post-injury did not significantly reduce footslip errors on the ladder task, nor did AIH administered at the same time as treadmill training improve ladder performance post-treatment (Fig. 5).…”

“…[15][16][17][18][19] To distinguish the effects of AIH per se from AIH combined with task-specific motor training, we treated SCI rats with repetitive AIH treatment with either ladder (task-specific) training, with no training, or with treadmill (nontask-specific) training. To examine the robustness of AIH effects, we performed separate experiments that examined recovery of distinct motor tasks that required either highly skilled use of the forepaw (two different reach-to-grasp tasks) or unskilled forepaw use (grip strength and spontaneous paw use preference).…”

Multichannel polymer scaffold seeded with activated Schwann cells and bone mesenchymal stem cells improves axonal regeneration and functional recovery after rat spinal cord injury

“…First, the complete transection model destroys the entire neural network at and around the spinal cord, which could distinguish between bona fide regeneration and other forms of regenerative growth and exclude self-recovery, reported in previous hemi-section and contusion SCI models [51][52][53] . Second, the complete transection model is a faithful model of spinal cord injury for translational cell transplantation [54] .…”