What is a dorsal rhizotomy, what does it treat, and what is its mechanism of action?
Dorsal rhizotomy is an ablative technique designed to reduce spasticity, particularly in children with cerebral palsy. It works by eliminating a pathologically hyperactive reflex arc between sensory and motor fibers from the same muscle group.
How is a dorsal rhizotomy performed and what are some possible complications?
- • While the procedure has evolved over the last century, the current technique, which is known as a selective dorsal rhizotomy, involves performing a laminectomy over the conus, isolating the dorsal/sensory nerve roots from L1 to the sacrum, dividing these roots into rootlets, recording EMG responses to tetanic stimulation from these rootlets, and sectioning rootlets that have diffuse responses that extend beyond their distribution. Approximately 60% to 70% of the sensory nerve roots are divided in this fashion. Possible complications of a modern dorsal rhizotomy include transient dysesthesias, with a low risk of permanent hypoesthesia, as well as transient urinary retention with a low risk of incontinence.