Basis, indications and risk

Treatments Basis, indications and risk Patient information Postural hygiene Exercise Maintaining level of Activity Bed rest Pharmacological therapy Neuroreflexotherapy (NRTI) Spinal column surgery Surgery for Pain and Pain Clinics Vertebral manipulation Behavioral treatment Epidural injections Facet joint infections Trigger point and ligament infections Rhizotomy Corsets and lumbar belts Traction Physical therapy/physiotherapy Electromyografic Feedback TENS: Transcutaneous electrical Nerve Stimulation Shoe insoles and shoe lifts Acupunture Recommended treatments

Rhizotomy

It is the destruction of the nerves in the facet joints, normally by burning them with radiofrequency current.

Objective

To improve pain in instances of facet joint degeneration.

Theoretical base

There are no nerves in the cartilage of the facet joint. These are located in the bone placed underneath. This is why joint degeneration may not cause problems until the bone is affected. When this occurs, pain nerves are activated, with the subsequent onset of pain.

Conceptually, rhizotomy aims at destroying the nerves in the facet joint to eliminate pain sensation. It is usually performed by burning the joint nerves. Obviously, this procedure is only considered in those cases in which pain is due to activation of these nerves by facet joint disorders.

However, each facet joint enfolds nerves from two, and in some individuals three, different vertebral levels. Thus, for example, the facet joint between the fourth and fifth lumbar vertebrae may receive nerves that originate from, for example, the third, fourth and fifth lumbar level. Therefore, nerve destruction of only one of these levels may have no effect, or have a temporary effect until the remaining nerves take on its nerve field.

Also, it was traditionally believed that all pain nerves reached the medulla through the posterior root, which permitted the localization of the site where nerves had to be destroyed to eliminate the pain originated in the facet joint. However, recent studies show that, although there are individual variations, in some individuals up to 20% of pain nerves reach the medulla through the anterior root. Muscle nerves also pass through this root so it cannot be destroyed since, in doing so, it would cause paralysis of the innervated muscles.

Evidence of efficacy

The existing recommendations based on scientific evidence do not consider studies on this topic.

Since the publication of those guidelines, some rigorous studies have been performed on this technique. In summary, these studies coincide in demonstrating that rhizotomy can be effective in a small subgroup of chronic patients. The key is to select them very meticulously with the criteria described in "indications" of this section.

Risks and contraindications

The inherent risks of surgery (infections, hemorrhage, etc.), although they rarely occur, and pain at the operation site, which persists during several days.

Indications

The existing evidence based recommendations do not recommend rhizotomy, essentially because they are focused on the treatment of acute cases and rhizotomy can only be considered in chronic cases.

It may only be indicated in cases that comply with the following criteria:

1. Characteristics of pain:
   1. local pain with no radiated pain nor signs of nervous compression (such as loss of strength or reflex or sensibility alterations)
   2. pain resistant to non-surgical treatments for more than 12 months.
2. Pain origin:
   1. Rhizotomy should not be performed on patients whose other organic alterations of the spine may explain the pain.
   2. - It must be assured that pain results from alterations of the facet joint. This is the most important criterium to recommend rhizotomy and also the most difficult one to prove. The detection of signs of joint degeneration through radiological test is not enough, since many healthy persons have it. To verify it, a test with anaesthetics is needed (see below).
3. Test with anaesthetics:
   1. - Before a rhizotomy treatment, an anaesthetic infiltration test at the joint should be done. If pain is due to the activation of nerves at the joint, pain should disappear completely. Some authors recommend doing three infiltrations spaced out in time; two with anaesthetics and one with a placebo (substance of similar appearance but with no effect), without letting the patient know which is which).
   2. - Rhizotomy should only be performed on those patients in which pain disappears completely with the anaesthetic injections and remains unchanged with the placebo shot.
4. Patients:
   1. - An adequate selection of patients is the key criterium to assure that Rhizotomy has acceptable chances of success.
   2. - It should only be considered on patients whose pain complies with the above described characteristics, after discarding that it may be due to any alteration different from that of the facet joint and where pain disappeared with the anaesthetic infiltrations.
   3. Technique:
   4. - The destruction of the root should be performed under radiologic control, to assure it is done in the right place.
   5. - The roots of, at least, two segments should be destroyed and two or three lesions should be made at each location, to accomodate personal variations in the course of the nerve.

Available studies suggest Rhizotomy in cases in which each and all of the requisites described are met and have:

1. Pain at the neck from injuries in the facet joint at some level between the seventh and third cervical vertebra (technically, it is very difficult to perform Rhizotomy at levels above this one), and in which the injury is due to a cervical whiplash (abrupt flexo-extension of the neck) caused by a car accident,
2. Lumbar pain.

Even when it is successful, the effect of rhizotomy tends to diminish with time.