Chronic unexplained widespread pain (WSP) and fibromyalgia (FM) are generally assumed centralized pain disorders. However, FM shows characteristics of neurological disorder. Moreover, there are similarities between FM, WSP and cerebrospinal pressure dysregulation syndromes such as idiopathic intracranial hypertension and idiopathic normal pressure hydrocephalus. When intracranial pressure increases, drainage of excess CSF through the cranial and the spinal nerves increases. Increased CSF pressure inside the nerves irritates the nerve fibers and consequently causes widespread radicular pain. We hypothesized that the neurological symptoms may be caused by CSP dysregulation and that withdrawal of spinal fluid might relieve the pain in patients suffering from FM and unexplained WSP.

Retrospectively, CSP measurements followed by spinal fluid taps in an attempt to relieve the pain were reviewed in 30 patients (12 males and 18 females, mean age 42.0 y+11.2 y) suffering from debilitating WSP and FM. Within the first week postpuncture, patients were asked to observe to list the most striking changes of their symptoms.

The opening pressure ranged from 12 to 32cm H20 (mean 19.7+4.8cm H20, median 20.0cm H20). In 21 patients (70%), spinal fluid withdrawal had a favorable effect on the pain from a few hours to 8 weeks. Other improvements were: relief of low back pain, leg pain and/or coccygodynia; disappearance of headache; improved concentration; improved mood; improved sleep; more clear in the head; being able to sit longer without pain; being able to walk better; no more urinary frequency; more easy to empty the bowel and/or the bladder; less pain in the jaw.

Exploring the issues on raised CSP may open perspectives for the diagnosis and treatment of unexplained WSP and fibromyalgia. In patients with chronic pain, when performing a lumbar puncture for diagnostic reasons, opening pressure should be measured.