An effective treatment for low back pain??
There are no really effective recognised treatments for back pain. If you are reading this with any personal interest you probably know this already.
However, the search goes on for a technique which could really make a difference to the lives of back pain sufferers. The latest claimant to the throne goes by the name of Intradiscal electrothermy.
Achieving more by doing less…
Recent advances in spinal surgery have concentrated on reducing the intervention to the minimum needed. Surgeons wish to reduce surgery-related trauma, patients are more aware of alternatives to open surgical procedures, and new technologies are continually being developed to treat lumbar disc herniation and discogenic pain due to degenerative disc disease. Intradiscal electrothermal therapy (IDET) is one of these new methods.
What’s involved in intradiscal electrothermy?
A specially designed thermal resistance probe is inserted into the disc and controlled heating of the intervertebral disc performed. The temperatures are high enough coagulate nerve endings and to contract collagen, the material making up much of an intervertebral disc. This may result in disc shrinkage and reduction in pain. IDET appears to be a safe procedure and perhaps an alternative to lumbar interbody fusion. Although the long term results are not yet clear, this technique appears to provide intermediate term relief of pain in patients with discogenic low back pain.
Types of pain treated with IDET
IDET can be seen as an alternative to Anterior Lumbar Interbody Fusion (ALIF), a major and significant operation which involves opening the abdomen and placing bone graft in the disc space, with metalwork also likely for fixation. The selection of suitable patients for this treatment may be the most important decision for a successful outcome.
The primary reason to treat someone with IDET is for discogenic pain, ie pain likely to have a disc related cause. Pain is usually continuous and persistent, in the low back, worse with upright weightbearing and better with lying down. The pain will have been present for at least 6 months, the low back pain being greater than any leg pain. This is a nocioceptive pain, ie due to tissue damage/injury.
In evaluating these patients, it is important to be sure a disc is the pain source. Magnetic resonance imaging can confirm the presence of disc degeneration, reduced water content and loss of disc height. This kind of therapy cannot treat disc fragments which may have prolapsed, but is aimed at the disc interior itself.
A radiologist may perform discography, which can be a useful confirmatory investigation. It can help identify the suspect level and flag up people who have multilevel disc changes, any (or many) of which might be pain sources. Potential patients should also have had nonsurgical treatments including physiotherapy and nonsteroidal antiinflammatory drugs. Basically, if you meet all the criteria for ALIF you could be offered IDET as an alternative.
People with multilevel degenerative disc disease, in whom multilevel ALIF is being considered, can benefit from treatment with both ALIF and IDET at certain levels, perhaps avoiding the fusion of more levels of the lumbar spine than necessary.
Reasons for not doing IDET
If there is lumbar instability which needs fusion, the presence of infection or malignancy or severe psychosocial issues. Multilevel disease (three or more levels of disc disease found on MRI and discography) is a caution but not an absolute block to IDET, as is more than 75% loss of normal disc height.
How intradiscal electrothermy is done
The technique is performed in an operating theatre with the patient on their front. The person is sedated throughout the procedure and x-ray guidance used to track the path of the catheter. The needle is inserted to avoid the nerve root which is exiting at the treated level, and directed toward the centre of the disc under x-ray guidance. The disc annulus (outer tough covering) is punctured, and the thermal catheter is inserted through the needle into the disc. The tip of the catheter is aimed toward the posterior aspect of the disc so that the heating parts of the catheter are placed on the symptomatic side. Once the catheter is successfully placed and its location confirmed by x-ray, the catheter temperature is gradually increased to 90°C and allowed to remain at that temperature for 4 minutes. The patients may be observed for 2 hours before discharge and are instructed to resume, as they can, their usual activities after 24 hours.
Things that can go wrong…
IDET appears to be a very safe procedure and few complications have been reported.
What’s the result?
Many favourable results have been shown in various studies but it not yet at all clear if this is a valuable therapy for those in low back pain. No serious complications have been reported.
Quick summary of IDET
Intradiscal electrothermal therapy seems to be safe and moderately effective in relieving pain due to disc problems. It may be an alternative to ALIF in patients who cannot or don’t wish to undergo a major fusion procedure. Complications are few and recovery time is minimal, especially compared with a spinal fusion. There is no evidence to suggest that IDET is harmful clinically or biomechanically. However, it has not yet been shown to have a valuable place in the overall treatment of low back pain.