Cervical spinal stenosis

Cervical spinal stenosis is a narrowing of the spinal canal in the neck. Its symptoms can included pain, numbness, tingling, weakness and other symptoms seen in cervical medullary syndrome.

Fibromyalgia
A study of 270 patients with fibromyalgia found that 46% had cervical spinal stenosis and 20% chiari malformation. A significant improvement in physical and mental well-being was found in patients with cervical stenosis who received surgery. A second study found that 71% had cervical spinal cord compression.

There are some cases of cervical stenosis that may not be apparent when the neck is in the neutral position, but may be quite severe in extension. Andrew Holman describes these cases as "positional cervical spinal cord compression." He argues that some symptoms of fibromyalgia may be an inflammatory response to intermittent cord irritation which may not be severe enough to cause more overt symptoms.

ME/CFS
A 2018 case study published by Peter Rowe found marked post-operative improvement of symptoms in three patients with severe myalgic encephalomyelitis, orthostatic intolerance and cervical spinal stenosis.