We perform minor injections in the office. These include trigger point injections and injections into bursae (hip (greater trochanteric) bursa) and ligaments (epicondylitis (Tennis and Golf elbow)).
The most commonly performed procedures include low back (lumbar) and neck (cervical) epidural steroid injections (often coming from the side that causes the pain, called transforaminal epidural steroid injections), cervical and lumbar facet joint (medial nerve branch) blocks and radio-frequency ablations (destruction of nerves that supply the facet joints).
Less common are sympathetic blocks for RSD-CRPS (Reflex Sympathetic Dystrophy-Complex Regional Pain Syndrome) which are done for the upper extremity as Stellate ganglion block and for the lower extremity as lumbar sympathetic block. They are usually done in a series to maximize pain relief.
Patients who have undergone previously spine operation and continue to have severe pain (especially in the extremities) could be candidates for a spinal cord stimulator system if all less invasive treatment options have failed.
Procedures – Facet Joint Ablations
Many patients can understand and visualize low back and leg pain that is due to a disc prolapse (herniation or extrusion). It makes intuitively sense that if you have disc material mechanically pushing on a nerve root it would cause irritation of the nerve root and therefore pain that is felt where the nerve is going (to put it in simplistic terms). Everybody has hit the “funny bone” at some time and can appreciate the sensation from a compressed/irritated or impinged nerve.
This is about structures in the spine (from the neck [cervical spine] to the low back [lumbar spine]) that most patients have never heard of before. We are talking about the facet joints (anatomically known as the zygopophysial or z-joints) – the unknown cause of chronic back pain.
Multiple studies have shown that between 25-50% of chronic low back and neck pain is caused by these small paired joints that connect vertebral bodies with each other.
Facet joints can cause pain depending on their level.
In the neck area the highest levels have shown to cause pain in the upper neck and head while the lower neck facet joints can cause pain all the way down to the shoulder blades. The upper levels can also cause headaches coming from the neck up (called cervicogenic headaches [headaches that are caused by neck problems]). Neck facet joint pain can be caused either by a traumatic event (whip-lash injury) or degenerative arthritis or a combination of both.
In the low back the pain is usually described as a band going across from the mid line to the sides with sometimes radiation into the hips. Rarely (about 5% of cases) will patients with lumbar facet arthritis have pain going past the knee. The more common culprit for pain that shoots past the knee is a disc herniation causing irritation of a nerve root (“sciatica”). Facet joint pain is usually aggravated by certain positions. Quite often the patient will complain of pain leaning forward (doing dishes, cooking), vacuuming or trying to get up from a sitting position. This is not very specific as a disc herniation can also cause increased pain with leaning forward. Often leaning backwards, rotating and bending sideways can increase pain due to facet joint arthritis.
Why do patients get facet joint arthritis? The simple answer is that facet joints are not any different than other major joints in the body from the hips to the knees and shoulders and they are subject to the same kind of trauma and degeneration (wear and tear) like all the other joints. There is also a relationship between degenerated discs accelerating facet joint arthritis as the facet joint have to bear more weight at a level with a degenerated disc. It is also well known that patients who underwent neck and back operations, especially fusions often have significant facet arthritis. This is probably due to changes in biomechanics with the facet joints taking a higher stress load at, below and above the operated part of the spine.
What can be done for facet joint pain? The first step is to establish a diagnosis. Unfortunately, there are no good ways to diagnose facet joint pain but with nerve blocks. There is poor correlation with imaging studies. An x-ray image, CT or MRI showing bone spurs at the facet joints does not prove that the pain is coming from those structures. The corollary is that normal appearing facet joints can indeed be causing significant pain. Some studies suggest that paramedian tenderness (meaning tenderness 1-2 inches off the mid line) can correlate with facet joint arthritis.
The gold standard for the diagnosis of facet joint pain is the differential local anesthetic block meaning that you inject at two different times two different kinds of local anesthetics (with various duration of action) right next to the nerve that goes into the joint and have the patient give you feedback about the duration of relief. If the patient has good relief with both local anesthetics but longer with the longer acting local anesthetic then the probability of the pain coming mainly from the facet joints is very high. It is quite common for the patient to have very good pain relief for the duration of the local anesthetic (comparable to the time it takes for your cheek to feel normal after a local anesthetic injection by a dentist) only to have the pain go back to the original level rather abruptly after the local anesthetic wears off. The most common comment I hear is “The pain came back with a vengeance”. The successful test injection shows patients how comfortable they were in the past with the decrease or absence of pain being called “striking”. Although ideally two different blocks should be done to decrease the risk of false positive results, this puts a heavy financial burden on the patient and most insurance companies will allow to proceed with the ablations after one successful block.
Once it has been established that a major part of the pain is coming from these facet joints, the standard of care is to denervate the nerve innervating the joint (medial nerve branch at C2 to C7 and T12 to L4 and dorsal branch at L5) using heat (radio-frequency ablation) at 80 degree Centigrade which is about 140 degree Fahrenheit for 90 seconds to denervate the nerve branch. Before the heating it is checked to make sure that the needle tip is not too close to the main nerve root. This is done by verifying the position of the needle tips on live X-ray (fluoroscopy) and also by sending electric impulses through the cannula. Patients will feel some tingling, pressure, pain or pulsating in their necks and low backs. These test impulses should not be felt in the arms and very rarely below the hips. The “burning” of the nerve usually silences the nerve for 8-12 months at which time it slowly regenerates. Most patients enjoy the relief from the RF and come back to have the procedure done again. The insurance companies do not request another test injection as the diagnosis has been established. They will allow to re-burn the second time around without demanding to re-test.
What happens if the facet joint blocks (test injections) do not provide the patient with any meaningful (usually over 50%) relief? If that is the case and there were no technical issues, then it means that the pain is not coming from the facet joints but from other structures like the intervertebral discs or in the low back from the sacro-iliac joints.