Recovery of locomotor function in adult paraplegic frogs by inductive lability in the distal isolated spinal cord neural networks

SPINAL CORD INJURY: REVERSING THE INCORRECT CORTICAL MAPS BY INDUCTIVE LABILITY PROCEDURE

Within the brain-stem and on the cerebral cortex there are locomotor control centers arranged in a ladder-form control system. These centers are somatotopic, self-organizing neural network maps capable of simultaneously learning and task execution. In spinal cord injury (SCI) these self-organized maps get erroneously re-organized and maladaptively stabilized. The extent and quality of sensory-motor recovery, if any appears, is affected by and compromised due to incorrect mapping processes. The treatment method based on inductive lability procedure (Krishnan, 2003a, 2003b, 2003c) uses botulinum toxin for the purpose. It recreates competition among synapses in a locomotor training-based corrective re-self-organization of the maps in various steps of the ladder.

A new extra-vertebral treatment model for incomplete spinal cord injuries

Advances made in recent times in spinal cord injury repair research will soon take us toward a cure in paraplegics. But what are the prospects for quadriplegics? Certain fundamental issues make treatment approaches to quadriplegia different and difficult. Injury at cervical region poses additional problems for any surgical intervention with life-threatening risks of i) endangering respiratory function, ii) cavitation, cysts, and syringomyelia formation extending cephalad to the injury, and iii) mid-lower cervical injuries, lower motor neuron death, and the resultant degeneration of brachial plexus axons would still leave the upper limbs denervated and paralyzed even as treatment procedures might successfully salvage the lower limbs. With these apparently insurmountable impediments in quadriplegic cord repair, it would be wise to turn to alternative treatment strategies. Conventional treatment models since the days of Ralph Gerard (1940) have all used intra-vertebral procedures. We present here a plausible extra-vertebral repair model suitable for incomplete cord injuries at cervical, thoracic, and lumbar levels. The procedure consists of identifying the extent of viable grey-white matter in the injured area and to utilize it efficiently as a "neural tissue bridge." Next, labile state is induced by using botulinum toxin/colchicine (Krishnan, 1983, 1991; Krishnan et al., 2001 a,b) and Ca+ channel blockers in the motorsensory nerve terminals of polisegmentally innervated skeletal muscles that "bridge" the injured cord segments. This would retrogradely induce a redundant state of intra-spinal growth of nerve terminals and new synaptic connections within those viable neural tissues, as well as promote effective relinking of the injured cord ends and enhance motor-sensory recovery.