In order to improve the accuracy and reliability of the electrodes implant location when using spinal functional electrical stimulation to rebuild hindlimb motor function, we measured the distributions of function core regions in rat spinal cord associated with hindlimb movements. In this study, we utilized three-dimensional scanning intraspinal microstimulation technology to stimulate the rat spinal cord to generate hip, knee and ankle joint movements, and acquired the coordinates of the sites in spinal cord which evoked these movements. In this article, 12 SD rats were used to overcome the individual differences in the functional region of the spinal cord. After normalized and overlaid the messages, we obtained the function core regions in spinal cord associated with ankle dorsiflexion movement, hip flexion movement, hip extension movement and hip adduction movement. It provides a reference for rebuilding the hindlimb movement function with micro-electronic neural bridge.
Functional electronic stimulation (FES) may provide a means to restore motor function in patients with spinal cord injuries. The goal of this study is to determine the regions in the spinal cord controlling different hindlimb movements in the rats. Normalization was used for the regions dominating the corresponding movements. It has been verified that FES can be used in motor function recovery of the hindlimb. The spinal cord was stimulated by FES with a three-dimensional scan mode in experiments. The results show that stimulation through the electrodes implanted in the ventral locations of the lumbosacral enlargement can produce coordinated single- and multi-joint hindlimb movements. A variety of different hindlimb movements can be induced with the appropriate stimulation sites, and movement vectors of the hindlimb cover the full range of movement directions in the sagittal plane of the hindlimb. This article drew a map about spinal cord motor function of the rat. The regions in the spinal cord which control corresponding movements are normalized. The data in the study provide guidance about the location of electrode tips in the follow-up experiments.
Intraspinal microstimulation (ISMS) is a rehabilitation technology that activates muscle movement by electrically stimulating the spinal cord, thereby restoring the function of paralyzed limbs. In this study, a fuzzy logic-controlled self-tuning proportional-integral-derivative (PID) algorithm was adopted. By simultaneously adjusting three key electrical stimulation parameters—amplitude, pulse width, and frequency of the pulse signal—the distal locomotor central pattern generator (CPG) in rats with spinal cord injury (SCI) was activated, realizing real-time control of hindlimb ankle joint movement in paralyzed rats. To verify the control performance of the intraspinal microstimulation system, animal experiments were conducted. Statistical results showed that the root mean square error (RMSE) of joint angle tracking was 2.50°, and the normalized root mean square error (NRMSE) was 5.78%. The results indicate that the ankle joint of the paralyzed hindlimb in SCI rats can move according to the preset angle trajectory through single-electrode intraspinal electrical stimulation.
