Return of spinal reflex after spinal cord surgery for brachial plexus avulsion injury

Abstract

Motor but not sensory function has been described after spinal cord surgery in patients with brachial plexus avulsion injury. In the featured case, motor-related nerve roots as well as sensory spinal nerves distal to the dorsal root ganglion were reconnected to neurons in the ventral and dorsal horns of the spinal cord by implanting nerve grafts. Peripheral and sensory functions were assessed 10 years after an accident and subsequent spinal cord surgery. The biceps stretch reflex could be elicited, and electrophysiological testing demonstrated a Hoffman reflex, or Hreflex, in the biceps muscle when the musculocutaneous nerve was stimulated. Functional MR imaging demonstrated sensory motor cortex activities on active as well as passive elbow flexion. Quantitative sensory testing and contact heat evoked potential stimulation did not detect any cutaneous sensory function, however. To the best of the authors' knowledge, this case represents the first time that spinal cord surgery could restore not only motor function but also proprioception completing a spinal reflex arch.