Epidural opiates and degenerative back pain.

THE relief of acute pain by epidural and intrathecal opiates has been widely explored in the past few years. The existence of spinal opioid or endorphin receptor sites explains the excellent analgesia which can be achieved by these routes. It is interesting that endorphin levels in the cerebrospinal fluid have been shown to be markedly lower than normal in both acute and chronic pain.' Most studies using spinal opiate administration have been in patients with acute pain. Patients with intractable pain due to degenerative bony changes in the spine are most frequently managed with non-steroidal anti-inflammatory agents, but these have to be taken frequently, are not without side-effects, and often are ineffective. The aim of this study was to find whether such pain could be alleviated for a prolonged period using a single administration of epidural opiate.