Overview of Provocative Discography
Provocative discography (PD) is a process used to identify if a person’s chronic back pain is coming from a specific disc in their spine. This procedure involves injecting a special dye, called contrast, into the soft, jelly-like center (nucleus pulposus) of a spinal disc. This is based on the idea that spinal discs can be a source of back pain, and a damaged or disrupted disc would hurt when put under pressure; so, it should also cause pain when filled with this dye. Ultimately, this test helps your doctor pin-point the source of your chronic back pain.
Anatomy and Physiology of Provocative Discography
The intervertebral disc is a part of your backbone that helps to spread out pressure evenly throughout your spine while enabling actions like bending, stretching, and rotating. The inside part of the disc, called the nucleus pulposus, is made up mostly of water-filled gel and a network of a substance called proteoglycan, playing a big part in absorbing shock. The exterior part of the disc is named the annulus fibrosis. It’s made up of several layers of a tough fiber known as collagen, which attaches the disc to the plates at the ends of the vertebrae. It’s designed to strengthen the spine and allows it to handle twisting pressures. However, sometimes small tears can appear primarily in the back and side-back segments, causing parts of the nucleus pulposus to push outwards. Specifically, the outer segment of the annulus is equipped with a lot of nerves, so when this happens, even a little bit of pressure can feel very painful.
If you’re experiencing pain due to issues with a lumbar disc (a disc in your lower back), the pain often sits in the middle of the back and may spread across your back and/or into the buttocks and back of your thighs. Sometimes, this pain might also reach your groin or below the knee. Generally, actions like prolonged sitting, bending forward, changing from sitting to standing, doing sit-ups or holding your breath and straining (also known as a Valsalva maneuver), and rotating your body when it’s under pressure could increase this type of pain. On the other hand, pain from a damaged disc in the neck (cervical) or middle of the back (thoracic) is usually less predictable and can manifest in various ways.
You can use advanced imaging techniques like Magnetic Resonance Imaging (MRI) to predict with a reasonable degree of accuracy if your lower back pain is due to issues with a disc. Signs to look out for would include the presence of a high-intensity zone, which indicates leakage of nuclear material, changes in the bone next to the disc larger than one-third of the adjacent vertebral body height, and the core of the disc appearing dark in the MRI scan.
Why do People Need Provocative Discography
Discography, a test for checking spine pain, should only be used if there’s a strong reason to believe the pain is coming from the spinal discs. This belief is normally based on the person’s symptoms and findings from detailed imaging examinations. The information gathered from the procedure is then used to rule out certain conditions or to plan the next steps for treatment. These might include various disk-focused therapies (like heat treatments, treatments using radio waves, or regenerative medicine), or potentially surgery (such as disc replacement or spinal fusion).
When a Person Should Avoid Provocative Discography
There are certain situations where a special type of test, called provocative discography (PD), is not recommended for people suffering from chronic, unspecific back pain. This test should not be used if a person with the back pain hasn’t tried conservative treatments – like rest, physical therapy, or medication – yet. It also should not be used if the soft cushions between the bones in your backbone (known as intervertebral discs) look normal when examined using imaging techniques.
Doctors may also choose not to use PD if the patient has a lot of stress in their life or a mood disorder that isn’t well managed. This is because these factors can make it more likely that the test results are misleading, or “false-positive”. Just like other invasive procedures that involve your spine, there are several reasons why PD can’t be done, including if the patient doesn’t want to do it, has an untreated infection, or has health problems that affect their blood’s ability to clot (known as coagulopathy) or decrease their platelet count (thrombocytopenia).
People who are allergic to both types of a special dye (known as contrast), which is used to make certain areas of the body show up more clearly on imaging tests, should also not have this test.
How is Provocative Discography performed
The Spine Intervention Society (a group of experts in spine interventions also previously known as the International Spine Intervention Society) has established carefully researched guidelines for a procedure known as PD.
PD, which is carried out using x-ray technology for detailed imagery, is done in a special procedure room. The patient is typically laid on their stomach, except for specific cases related to the neck where the patient lies on their back. Precautions are taken to ensure cleanliness and prevent infection; these include using special cleaning products, covering the patient with a sterile sheet, and administering antibiotics. Doctors are advised to thoroughly clean their hands and arms, wear a clean gown and two pairs of gloves, and be very careful not to touch the part of the needle that will enter the disc. It’s crucial not to heavily sedate the patient, so that they can provide real-time feedback; local anesthetic or light sedatives like valium are used to keep the patient comfortable.
The doctor uses fluoroscopy – a type of imaging that shows a continuous x-ray image on a monitor – to guide a small needle into each disc that needs to be tested. Next, a contrast substance is injected sequentially into these discs to increase the clarity of the images.
The patient’s reaction to each injection is observed and recorded. If the patient’s reaction is similar to their usual spine pain, the test is successful. However, if the patient’s reaction is different from their usual pain, the test is unsuccessful. The results are considered valid if several conditions are met, such as the patient being alert enough to give reliable feedback.
Some experts suggest injecting local anesthetic after the initial pressure test to help increase the accuracy of the diagnosis, but there’s ongoing debate about this. After the conclusion of the test, the patient may have a post-procedure CT scan – a type of X-ray that makes detailed pictures of structures inside of the body – this helps doctors to get a clearer and more detailed visual of the disc compared to the fluoroscope.
Possible Complications of Provocative Discography
The procedure known as PD does carry some potential risks. These may include different types of infection such as ‘discitis’ (inflammation of the intervertebral disc space) or ‘osteomyelitis’ (infection in the bone). Additional risks include bleeding, accidental piercing of the outermost layer of the spinal cord (known as ‘dural puncture’), rapid disc damage caused by too much pressure from the contrast material, further worsening of existing disc damage or decay, continuous pain after the procedure, allergic reactions, and potential harm to other body parts that are near the injection site such as spinal nerves or kidneys.
What Else Should I Know About Provocative Discography?
PD, short for provocative discography, is a method used to determine if spine pain is caused by a problem with your discs, the shock-absorbing pads between the bones in your spine. It has been used for many years and is considered quite effective. But it’s being used less frequently these days for a few reasons.
Firstly, PD is an invasive procedure, meaning that it involves going inside the body, which always comes with certain risks. There are concerns that testing the discs in this way could damage them, leading them to wear out more quickly.
Secondly, there has been criticism that PD can give false-positive results, suggesting a problem where there isn’t one. This idea is mostly based on older research; when more recent data was analyzed by a group called the Spine Intervention Society (SIS), it was found that, assuming protocols were strictly followed, the rate of false positives was actually quite low for patients that didn’t have particular complicating factors like pre-existing psychological conditions affecting the body or previous back surgery.
Thirdly, PD has proven unreliable in predicting the success of spinal fusion surgery, a procedure which joins together the vertebrae, or bones in your spine, to relieve chronic spine pain. However, it’s worth noting here that this surgery is known to have a variable success rate for this specific indication.
Lastly, advances in technology have improved our ability to visualize disc structure with another medical imaging test called MRI, which stands for Magnetic Resonance Imaging. MRI scans have shown certain characteristics tied to disc-related lower back pain.
Understanding these issues can help you and your doctor to make the right treatment choices for your back pain.
