Wilson, Peter R.

Cervical arthrography was performed on 13 patients with putative cervical facet symptoms. Under fluoroscopic control, injection of radiopaque dye, local anesthetic, and depot steroid into the affected joint capsule was performed without complication. Eleven of the 13 patients had partial to complete pain relief during the 2-week to 6-month followup period.

Physiological events involved in nociception and pain perception are examined. Substance P could be a primary afferent transmitter of certain nociceptive information. Transmission of this information can be modulated within the spinal cord by intrinsic and descending mechanisms. The intrinsic mechanism involves inhibitory opiate effects within substantia gelatinosa. Centres for descending systems are located in medulla and periaqueductal gray matter. They are activated by exogenous narcotic agonists, and by regional connections. Descending inhibitory pathways are serotonergic and noradrenergic. GABA and glycine are also possibly involved in antinociception. Narcotics have been shown to produce analgesia when administered to the intrathecal or epidural spaces of humans. These routes are still experimental. The place of clinical modification of transmitter system is discussed, but no conclusions or recommendations can be made at this early stage.