Overview of Intradiscal Electrothermal Therapy
Low back pain is a very common and often debilitating condition. The causes vary depending on the individual but most often it results from mechanical issues within the spine. These can be problems with the facet joints (the small joints at each segment of the spine that provide stability and enable spine movement), damage to the spinal discs (soft cushions between the bones in your spine), narrowing of the spinal canal (spinal stenosis), disc protrusions (herniations), or cracks in the spinal joints (spondylolysis). Particularly, pain from damaged spinal discs is responsible for 30-40% of low back pain cases. Various treatments have been developed to tackle this issue specifically.
Intradiscal electrothermal therapy, or IDET, is a minimally invasive surgical method used to treat chronic low back pain resulting from disc damage. The process involves heating the outer layer of the spinal disc (known as the annulus fibrosus) with help of a special catheter, a tube with a controlled heating coil. The purpose of applying heat to the disc is to damage the nerve fibers which send pain signals, tighten the collagen (a protein that shapes the structure of the disc), and make the disc tissue stiffer. This could potentially mend tiny tears in the disc and regulate the release of substances that form the disc’s structure.
Anatomy and Physiology of Intradiscal Electrothermal Therapy
The intervertebral disc is essentially a tough, flexible cushion that exists between the bones of your spine. It consists of two parts: the nucleus pulposus (a squishy, fluid-filled center) and the annulus fibrosus (a tough, fibrous outer layer). These discs work like shock absorbers for your spine, helping it handle forces and move smoothly.
Think of it like this: if the spine is a stack of blocks, then the intervertebral discs are the squishy spacers keeping those blocks from grinding against each other.
However, these discs can start to break down over time due to factors like age, strain or injury. This might lead to inflammation, dehydration of the nucleus pulposus (the disc’s fluid-filled center shrivels up), reduction in disc height, and tears in the annulus fibrosus, which is the outer ring of the disc.
This disc damage can lead to something called discogenic pain. This pain isn’t because of an injury to the nerves in your back, but instead, comes from nerve signals being sent from nerves located in the outer layers of the disc. This can occur when there are tears in the annulus fibrosus that trigger pain sensors and inflammatory responses. Low back pain may also be caused by a problem in the nucleus pulposus and the plate of the vertebra that irritates the outer layer of the disc.
This discogenic pain can lead to long term low back pain without any leg pain (sciatica). This type of pain usually worsens with activities like exercise, coughing, and certain movements that increase pressure in your stomach area (known as the Valsalva maneuver). The physical examination for this condition differs from a slipped or herniated disc where the pain is triggered by lifting your straight leg.
Why do People Need Intradiscal Electrothermal Therapy
IDET, or Intradiscal Electrothermal Therapy, is a treatment option for chronic lower back pain that originates from a disc in the spine. This type of therapy is usually recommended for individuals who have had persistent lower back pain for at least three to six months and have not found relief from traditional methods. These traditional methods can include taking anti-inflammatory medication, physical therapy, and rest.
Before a person can be considered for IDET, a doctor will perform a physical examination. This can involve tests such as a straight leg raise and various neurological assessments to measure your limb strength and reflexes. These tests help to confirm that the pain isn’t due to a problem with a nerve root in the spine.
Fitting the criteria for IDET involves more than just experiencing ongoing lower back pain. Some of the criteria include: having tried and not responded to non-surgical treatment; displaying no signs of sciatica, a condition involving leg pain stemming from a pinched nerve in the lower back; having an MRI scan that shows no signs of a compressed nerve or spinal narrowing; showing annular tears or disc protrusions on an MRI; and having at least half of the disc’s original height remaining.
Before starting the actual IDET procedure, your doctor may perform what is called a provocative discography. This procedure involves injecting contrast dye into the affected disc to reproduce the pain and reveal any abnormalities in the disc. However, this test is usually reserved for those cases where other tests have not provided a definite diagnosis. It’s worth noting that research has shown a provocative discography can sometimes lead to increased disc damage and is only used when necessary.
If conservative treatments or less intrusive procedures like epidural injections don’t improve your chronic lumbar back pain, surgery might be a consideration. Available surgical treatments include spinal fusion, nerve decompression, and disc replacement.
When a Person Should Avoid Intradiscal Electrothermal Therapy
IDET, a procedure to help with back pain, may not be suitable for certain people. These include those who have very damaged spinal discs (the soft cushions between the bones of your spine have shrunk by more than half), a condition where a disc has slipped out of place or trapped a nerve, a narrowing of the space within your spine (spinal stenosis), or a disorder in which one bone in the back slides forward over the one below it (spondylolisthesis).
This treatment is also usually not suggested for those who have had back surgery before, particularly those who already underwent the IDET procedure in the past 6 months at the same location in the spine.
Equipment used for Intradiscal Electrothermal Therapy
It’s important to have the correct tools for the IDET procedure:
* A standard table that x-rays can pass through, with support frames and soft foam pads for your comfort.
* Biplanar fluoroscopy or C-Arm fluoroscopy, which are types of real-time x-ray machines. These allow the doctor to see exactly where he or she needs to work within the disc spaces in your spine.
* A set of tools which include a hollow needle, straight cannulae (a slim tube that is inserted into a cavity of the body, often to administer medication or drain off fluid), a temperature-controlled probe that delivers heat energy, and an IDET generator that powers the probe. These tools help the doctor to target the affected area with precise thermal (heat) energy.
Who is needed to perform Intradiscal Electrothermal Therapy?
In this situation, there are no extra medical staff needed. The team will usually include a spinal surgeon, who is a doctor especially trained to operate on the spine. Also, there’ll be a radiologist who uses medical imaging, like X-rays and MRI, to look at your body internally. There’s a registered nurse who will monitor your health and provide nursing care, an operating room nurse (also referred to as a circulator) who assists during the surgery, and an anesthesiologist. An anesthesiologist is a doctor who ensures you do not feel pain during the surgery by putting you to sleep.
Preparing for Intradiscal Electrothermal Therapy
Before the procedure, doctors need to give medical clearance. This involves assessing the patient’s health risks related to the surgery and making sure they’re in the best possible health condition. This step is important to ensure the safety and success of the surgery.
The procedure is done with the patient lying stomach-down on a specialized frame. The patient will be awake but relaxed due to a type of anesthesia called conscious sedation, combined with a local anesthetic to numb the area. This is an outpatient procedure, which means the patient can go home the same day after the procedure is done.
How is Intradiscal Electrothermal Therapy performed
Intradiscal Electrothermal Therapy (IDET) is a treatment for back pain that uses heat to alter a small portion of the affected intervertebral disc, thus relieving pain. It uses a catheter which is a small, flexible tube with a tip that can heat up. The catheter is carefully placed in the part of the disc that needs treatment.
Before the treatment starts, your doctor will give you an antibiotic. This is done to prevent infections during the procedure.
Before IDET, your doctor will identify which discs in your back are causing your pain. They use a method called discography, which can provoke the same pain you usually feel. This is done under a type of X-ray called a fluoroscope that allows the doctor to see your spine in real time. Then, a needle with a thin-tube inside it, is placed into the painful disc. This is done carefully, following a specific path to avoid hurting other parts of your back
For IDET, the doctor will insert a needle at the side of your back, again using x-ray images to guide it. The needle contains a flexible tube with a heatable tip. The point of entry on your back is selected by using the fluoroscope to visualize the backbone. The doctor advances the needle through a safe pathway until it reaches the damaged disc. Once there, the tip of the catheter is manipulated so that it circles the inner part of the disc, ending in the back part of the disc. Then, the needle is removed, the catheter is fixed in place and connected to the heat generator.
The healing begins by heating the tip of the catheter to 149 degrees Fahrenheit, and then it gradually increases to 194 degrees Fahrenheit over 12.5 minutes. This heat is then maintained for about 4 minutes. The exact duration and final temperature will depend on how well you tolerate the procedure. Do note, the procedure may last anywhere from 13.5 to 16.5 minutes.
During the procedure, antibiotics are used to prevent a potential spine infection. No other medications are introduced into the disc at this time.
If you have pain originating from multiple discs, the procedure can be repeated. However, usually no more than three levels (discs) are treated in one sitting.
Possible Complications of Intradiscal Electrothermal Therapy
If you’ve had discography or Intradiscal Electrothermal Therapy (IDET) – types of procedures used to diagnose or treat back pain respectively – you should know that these tend to have very low rates of complications. However, some patients may experience issues related to the procedures. Here are some potential complications:
- Radiculopathy: This is when a nerve in the spine is pinched, causing pain, numbness, or weakness that can spread to other parts of the body.
- Accelerated disc degeneration: This means the discs in your spine may wear down faster than usual. Discs are the cushion-like pads between your spinal bones (vertebrae), and when they wear down, it can cause pain and other problems.
- Endplates deformation: Endplates are the tough layers on the top and bottom of each disc. Deformation means these layers could change shape, which can cause pain and make it hard to move normally.
- Spondylodiscitis: This is an infection that can inflame the discs and vertebrae in your spine.
- Transthecal puncture route may result in post-procedural headache: Transthecal puncture route is a technique used during the procedure. Sometimes, it could lead to a headache after the procedure.
- Vertebral osteonecrosis: This is a condition where bone tissue in your vertebrae dies due to a lack of blood supply.
- Cauda equina syndrome: This is a serious condition that happens when the bundle of nerves at the bottom of your spine is compressed. It needs emergency treatment as it may cause pain, weakness, or numbness in the lower body.
What Else Should I Know About Intradiscal Electrothermal Therapy?
The way IDET, which stands for Intradiscal Electrothermal Therapy, works to ease pain is still a topic of discussion and there’s ongoing debate about how effective it really is. The belief is that IDET works by altering the structures within the disks of your spine, reducing pressure inside the disks (intradiscal pressure), numbing the area (annular denervation), and mending tear spots on the disks.
Honestly, there’s no definitive proof showing that IDET is consistently effective. In fact, there are well-documented cases where a dummy procedure (placebo or sham procedure) produced positive results, and there seems to be a link between the likelihood of a sham response and how invasive the procedure is. However, a number of clinical trials show that people have benefited from the procedure, and measurements of physical function show ongoing significant improvement between the first and second years after the procedure.
Going forward, it will be important to conduct rigorous studies to evaluate the outcomes and cost-effectiveness of IDET. These studies should take into account the technique used and selecting the right patients for the procedure.
