Spine-Pain

The symptoms of burning sensation affecting the feet, thought to be due to a distal small-fiber x neuropathy (DSFN) affecting somatic unmyelinated fibers, are usually accompanied by vasomotor or sudomotor changes suggestive of involvement of autonomic fibers. We therefore examined the relationship between pattern of anhidrosis and DSFN and its etiology, comparing patients with “pure” DSFN (with normal nerve conduction) to those with clinical DSFN (minor conduction abnormalities). We reviewed 125 cases with a clinical phenotype of DSFN. These patients had distal burning discomfort, variable sensory deficits, and intact motor function. All had undergone assessment with thermoregulatory sweat test (TST), autonomic reflex screen (ARS), and nerve conduction studies and electromyography (NCS/EMG). TST showed a distal pattern of anhidrosis in 74%. The quantitative sudomotor axon reflex test (QSART) was abnormal in 74%, with 80% of those having a length-dependent pattern of anhidrosis/hypohidrosis. In total, 93% of patients had a distal pattern of abnormality on QSART or TST. The Composite Autonomic Severity Score (CASS) was used to quantify the severity and distribution of autonomic deficits: 98% had CASS abnormality (sudomotor, 98%; adrenergic, 43%; cardiovagal, 35%). EMG was normal or showed unrelated abnormalities in 75%. The most common etiologies of DSFN were idiopathic (73%), presumed hereditary (18%), and diabetes (10%). Sudomotor examination is thus a highly sensitive detection tool in DSFN. Autonomic involvement is mainly distal, and additionally may involve adrenergic and the long cardiovagal fibers.

http://cat.inist.fr/?aModele=afficheN&cpsidt=17900365

Small fiber neuropathy is a relatively common disorder often associated with systemic conditions, such as diabetes, HIV, and vasculitis. Painful burning feet with diminished pain and temperature perception, and in some cases autonomic dysfunction, characterize this syndrome. Despite the magnitude of the symptoms there are few objective measures to identify and quantify these neuropathies. Skin biopsy and new immunohistochemical staining techniques have facilitated the evaluation of this syndrome.

Introduction. Peripheral neuropathies involve different populations of nerve fibers. Most patients present with large fiber neuropathies characterized by numbness, tingling, weakness, loss of deep tendon reflexes, and abnormal electrophysiologic studies. A more enigmatic group of patients present with severe pain and a paucity of findings on clinical examination and electrophysiologic studies. Many of these patients have small fiber neuropathies. The disparity of subjective sensory complaints to objective signs sometimes leads to an erroneous diagnosis of psychogenic pain. Patients with these syndromes are often difficult to treat. Thus, prompt evaluation and accurate identification of these syndromes is important.

http://www.thecni.org/reviews/13-2-p07-treihaft.htm

Discovery of the cells might lead to treatments, researchers say

THURSDAY, Nov. 1 (HealthDay News) — For the first time, researchers have found stem cells within the intervertebral discs of the human spine.

They say it may someday be possible to use these stem cells to help repair degenerating discs in order to treat neck and lower back pain.

The finding was published in the Nov. 1 issue of the journal Spine.

As spinal discs degenerate, cells are lost, and there’s a decrease is the ability to produce water-binding molecules called proteoglycans. Water absorbs force on the spine. The loss of proteoglycans can result in disc damage and pain.

http://abcnews.go.com/Health/Healthday/story?id=4509239&page=1

A MRI with and without contrast might reveal scar tissue as the source of pain.

For a patient who has already had spine surgery, the contrast agent has traditionally helped in differentiating a recurrent or remaining disc herniation from scar tissue.

Scar tissue and pain after back surgery

Effects of scar tissue on back pain and leg pain

The formation of scar tissue near the nerve root (also called epidural fibrosis) is a common occurrence after back surgery—so common, in fact, that it often occurs for patients with successful surgical outcomes as well as for patients with continued or recurrent leg pain and back pain. For this reason, the importance of scar tissue (epidural fibrosis) as a potential cause of postoperative pain—commonly called failed back surgery syndrome—is controversial.

http://www.spine-health.com/Topics/surg/scar/scar01.html

The prevalence of peripheral neuropathy is about 2% in the general population, but it rises to 12% and 17% in people with one or two recognised risk factors.1 Diabetes is one such risk factor and the most common cause of this disorder—about half of patients who have had diabetes for 25 years have peripheral neuropathy. The early symptoms of diabetic neuropathy and other peripheral neuropathies are due to degeneration of small somatic nerve fibres, which may remain the only nerves involved.2 However, “small fibre neuropathy” may not be detected by traditional physical, neurophysiological, and neuropathological tests. In the past decade, skin biopsy has become a popular method for investigating small nerve fibres.3 It allows general practitioners and non-specialists—such as diabetologists and specialists in orthopaedics—to diagnose neuropathy (thereby avoiding delayed or incorrect diagnosis), to investigate its aetiology, and to focus treatment, in particular for neuropathic pain.

http://www.bmj.com/cgi/content/extract/334/7604/1159

Watch out for digital nerves

Skin biopsy as indicated above carries a high risk of causing a digital nerve injury leading to a neuroma causing chronic pain, which may require reconstructive surgery. If volar digital skin biopsies are required then it is much safer to harvest these in the midline of the finger, but patients should be warned of the potential nerve injury and neuroma risk as important nerves are only a few millimetres under the skin surface.