Epidural anaesthesia and spinal arachnoiditis.

Six patients were referred to our hospital with spinal arachnoiditis after epidural anaesthesia performed one month to 3 years before the onset of symptoms. None had had previous lumbar surgery or trauma, intraspinal haemorrhage, infections or other known causative factors of arachnoiditis. All the patients were free of neurological symptoms before epidural anaesthesia and only two had transient distress in the period immediately following the procedure. The clinical signs and symptoms of spinal arachnoiditis were severe and in every case the diagnosis was confirmed by myelography. Three patients were confined to a wheelchair after 3 years of follow-up. To our knowledge, the anaesthetic procedures were performed according to standard methods. Arachnoiditis seems to be due to the epidural injection of foreign substances, and may be related to anaesthetic-vasoconstrictor solution or contaminants.