Long-term results of selective dorsal rhizotomy for hereditary spastic paraparesis.

Pure hereditary spastic paraparesis usually presents with progressive weakness and spasticity of the legs, which is similar to spastic cerebral palsy. In this study selective dorsal rhizotomy (SDR) was performed to improve the spasticity of pure hereditary spastic paraparesis and the long-term results were followed. A series of four patients with pure hereditary spastic paraparesis diagnosed by a multidisciplinary team received SDR. The dorsal rootlets from the L2 to S1 levels were selectively resected under electrophysiological monitoring. The patients were followed up for more than 2 years to evaluate the outcome of surgery. There was a significant reduction in muscular spasm after SDR. Standing and walking stability were improved in all patients which led to improvement in walking posture and longer walking distance without assistance. No urinary retention, cerebrospinal fluid leak, surgical infection or kyphosis occurred. For severe pure hereditary spastic paraparesis, SDR can reduce muscle spasm and improve standing and walking stability. These results were stable throughout follow-up. SDR performed at the level of the conus medullaris through a laminectomy from T12 to L1 or L1 to L2 requires a shorter incision, laminectomy of fewer segments, and has a shorter operation time than the usual method (laminectomy from L2 to S1). Intraoperative electrophysiological monitoring is helpful to discriminate abnormal rootlets and protect sphincter function.