As early as 1911 back and leg pain have been reported to arise from articular facet joints. These are the joints in the spine other than the intervertebral disk joint. Facet denervation (rhizotomy) has been successful in relieving chronic pain arising from abnormalities of the facet joint. This is an outpatient, percutaneous procedure for patients whose pain is not related to disk herniation. Other procedures are available for patients with disk herniation.
Percutaneous facet rhizotomy was developed in 1974 by Sheeley. Patients must undergo a selection process consisting of successful nerve blocks using a temporary anesthetic injected around the nerves of the facet joint. Only patients who experience significant pain relief for several hours are considered candidates for facet rhizotomy.
The actual rhizotomy is performed using a radiofrequency generator. The radio frequency probe is placed with the tip just lateral to the eye of the radiographic "Scotty Dog" (Figs. 1 & 2). At this location the facet nerve (nerve of Luschka) is blocked by the radio frequency generator. Patients with chronic back or leg pain in whom organic pathology has been eliminated can be the most difficult patients to treat. Often they are shunted from doctor to doctor or labeled with such terms as "functional" or as having "chronic lumbosacral strain". Lumbar percutaneous rhizotomy offers hope to a significant number of patients with chronic back pain. |