Although pain is a prominent symptom in patients suffering from syringomyelia, and this central neuropathic pain is very difficult to treat. However, more than half of all patients with syringomyelia suffer from symptoms related to central neuropathic pain. In the video you can see one of our patients, suffering from syringomyelia telling his story and reporting the effect of our treatment of the neuropathic pain:

Patients often present with complaints of radicular pain and/or central cord pain. Furthermore, nearly half of all patients with syringomyelia experience neuropathic dysesthetic pain, like burning sensation and/or pins and needles. ^[1] But only small series of patients are available as a base for these figures. In patients suffering from this type of central neuropathic pain, it is often an overwhelming and disabling symptom that over-shadows many of the other complaints, such as decrease in temperature sensation and numbness. Similar central neuropathic pain can be found in other spinal cord pathological conditions such as intramedullary tumors, multiple sclerosis and infarctions. ^[2]

Pain in syringomyelia and surgery 

Surgical treatment of syringomyelia resulted in improvement of dysesthetic pain in nearly half of a small series of patients (37), but a significant number of patients (41%) reported no improvement or an intensification of pain despite the operation. Improvement in pain status following operation seems difficult to predict. ^[3] Postoperative neuropathic pain is disabling  and responds poorly to treatment with analgesics, sedatives and antiepileptics. ^[4] To date, there is no consensus as to the best pharmacological treatment for pain in syringomyelia. ^[5] No clinical trials have been conducted yet. 

Integrated Medicine Concept in pain in syringomyelia 

In our centre we follow the normal steps for treating central neuropathic pain, and mostly prescribe two or more analgesics, such as low dose amitriptyline (10 - 50 mg per day) combined with either gabapentin (1800 - 2400 mg per day) or pregabalin (150 - 600 mg per day)and/or tramadol. However, there are patients non responding to these drugs. One of our patients did not respond to the drugs mentioned above, but did respond favourable to a topcial cream we developed in our centre, based isosorbidedinitrate(ISDN)0.4%, capsaicin 0.075%, and lidocaine 3%.

A challenge-rechallenge paradigm was followed. The pain decreased by using this topical cream from score 8 to 5 (11 points Likert scale) and after stopping the cream, the pain was rebouding to score 8 in a few weeks. Starting again using this cream reduced the painscore again, and in  a preriod of several weeks the pain decreased for more than 30% compared to baseline.

In one of the few articles with a focus on dysesthetic pain in syringomyelia we find the folowing analysis:

Pain is a disabling and pervasive problem for patients with syringomyelia. It is present in various forms, and often times medical or operative therapies are ineffective. An understanding of the causes requires thorough knowledge of the anatomical, physiological, and neurochemical factors.

There are three main groups of theories that support the existence of centrally mediated pain.

The first is the loss of a sensory balance. Beric, et al., have suggested that post-SCI dysesthetic pain may be secondary to a disjunction between the anterolateral pain pathways and the dorsal column sensory pathways.

The second and third theories relate to loss of spinal cord inhibitions and the release of spinal cord nociceptive neuronal firing. In addition to these physiological theories, neurochemicals are also thought to be involved in spinal cord pain pathways.

Our group has found the presence of substance P changes in patients with syringomyelia. It is likely that the numerous other peptides and nonpeptides involved in nociception may be altered by this spinal cavitary lesion and thereby affect the physiological mechanisms previously mentioned.

Gamma-aminobutyric acid and other neurotransmitters in syringomyelia

Gamma-aminobutyric acid is a well-known inhibitory transmitter in the central nervous system. The authors of some studies have shown this to be localized in the dorsal horn of the spinal cord. It is highly possible that with the loss of this transmitter "disinhibition" of pain pathways may occur.

In addition to substance P, there are a large number of potential neurotransmitters (or neuromodulators) whose concentration within the spinal cord may change with injury or the development of a syrinx. These include endogenous opioids such as endorphins and enkephalins, calcitonin gene-related peptide, cholecystokinin, neuropeptide Y, nociceptin, and vasoactive intestinal peptide. ^[6]

March 2010, Jan M. Keppel Hesselink, MD, PhD, David J Kopsky, MD 

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