What is facet joint pain?

I spent a lot of time on the last podcast talking about the term soft tissue.  As I’m sure you are aware I hate the term soft tissue.  Today I want to spend time discussing another type of injury that is often categorized by insurance adjusters as a soft tissue injury.  This study is all about facet joints or the bony joints in the back of the vertebra.  These bony structures are not soft at all, but hard.  If we are going off of the AMA Guides to the Evaluation of Permanent Impairment then facet joint pain would most of the time fall under the soft tissue category. 

Today’s study is Prevalence of Facet Joint Pain in Chronic Spinal Pain of Cervical, Thoracic and lumbar regions by laxmaiah macnhikanti et al published in the BMC musculoskeletal disorders journal in 2004.  This study was set up to determine how many people with chronic spinal pain have facet joint pain. 

There are multiple locations in the spine that can be pain generators.  There are discs, ligaments, muscles, tendons, nerves, spinal cord, bones, joints and other organ systems that can lead to spinal pain.  This study reported that in the general population 66% of people have spinal pain in their life.  Of all of these people 44% will have cervical pain, 56% will have lumbar pain and 15% will have thoracic spine pain.  This study reported that clinical examination alone can only determine the cause of the pain in 15% of patients.  

This means that 85% of the time a clinical examination will be unable to accurately diagnose spinal pain.  We often use advanced imaging and testing to determine the exact cause of spinal pain.  Today’s study reported that there are four factors that are necessary for any structure to be deemed a cause of back pain.  The first is a nerve supply to the structure.  As we talked about in a prior podcast the vertebral discs are the most aneural structure in the human body and do not have the ability to feel pain when healthy.  Or at least the inside of a healthy disc can’t feel pain.   The second is the ability of the structure to cause pain similar to that seen clinically in normal volunteers.  The third is the structure’s susceptibility to painful diseases or injuries.  The fourth is to demonstrate that the structure can be a source of pain in patients using diagnostic techniques of know reliability and validity. 

I think this is a good list of 4 things needed to show that pain can be coming from a specific part of anatomy.  I disagree with this article when they say these 4 things are needed to show a cause of back pain.  In my experience the anatomy that is experiencing the pain may not be the cause of the spine pain.  For example when a patient has ligament damage the mechanics of the spine are altered.  The reflexive control ligaments have over muscles is often lost with ligament damage and this leads to abnormal muscle patterns including muscle spasms.  This alteration of motion in the spine places a significant load on facet joints and as seen in today’s study facet joints are well innervated by the medial branch of the dorsal rami and have the ability to feel a lot of pain.  In this circumstance I explained the cause of the spinal pain is ligament damage, but the anatomy that is sending pain signals to the brain is often the facets.  This is why facet treatments like rhizotomies only temporarily resolve the pain because the primary injury had nothing to do with the facets.   

Today’s study showed that not only are facets capable of causing spinal pain, but they are capable of causing referred pain to the head, upper extremity, chest and lower extremities.  This study showed that imaging provides little additional useful information in diagnosing facet pain.  In the 90’s physicians started using diagnostic blocks to diagnosis facet pain.  These blocks typically use lidocaine to numb or block the nerves going from the facets to the brain to signal there is pain.  This process should lead to significant pain reduction, but for only a few hours.  This is not a treatment, but a diagnostic tool to see if the facets are sending a pain signal to the brain. 

This study showed that low back pain following a work-related injury or motor vehicle collision was facet mediated pain 15% of the time.  This study was set up to evaluate chronic spinal pain patients that failed conservative care which they reported as physical therapy, chiropractic care, exercise, drug therapy and bedrest.  They wanted to know what percentage of these chronic spine patients with failed conservative care had facet mediated pain.   They took 585 patients with spine pain and ruled out any patients with disc related pain by excluding patients with radicular nature pain, neurological deficits or imaging showing disc damage.   They ended up with 500 patients that qualified for the study. 

They took the patients and did the 1% lidocaine injections to see if the spinal pain while doing provocative tests was at a minimum 80% better for at least 2 hours.  For the patients that felt better they had them come back and do another injection of 0.25% bupivacaine.  They showed that 66% chronic cervical spine patient’s had cervical facet pain, 57% of thoracic spine pain patients had facet pain and 63% of the lumbar spine pain patients had facet pain. 

They admitted that a flaw in their study was no evaluating other potential sources of pain.  I feel like this study did a great job of showing a lot of chronic spine pain patients have pain signals coming from the facets.  Given the lack of evaluating other potential sources of pain I believe we can say the facets often have pain, but can’t say that they alone are the cause for their pain.   As a chiropractor I spend a lot of time treating biomechanical dysfunction.  This biomechanical dysfunction is lack of normal movement in facet joints.  This lack of movement is typically caused by job, posture, mattress, hobbies, injuries, stress, and just life’s stresses.  As a chiropractor I have great success treating facet pain.  The facet pain seems to return weeks to months after care and can be very chronic as seen in this study.  This is due to the fact that the facets take a lot of stress from daily life as well as other injuries.  These facets are easy to treat, but difficult to resolve.

The reason facet pain is difficult to resolve is that we rarely are able to change the primary cause.  We are unable to change jobs, posture, mattress, injuries stress, hobbies and other daily stresses on the facets.  This constant stress placed on facets can lead to ongoing chronic problems.  Also if we have ligament damage then as we discussed already this places a large stress of facets and patients often feel the pain in the facets. 

This study is helpful to understand that there are a lot of patients in motor vehicle collisions that we do not have objective evidence of an injury, but have ongoing chronic pain.  This study showed that a majority of these patients likely have facet pain.  Without any objective evidence of an injury this type of injury will qualify for the soft tissue category for impairment ratings.  However, this is a serious injury that can cause ongoing chronic pain. 

Real World Example

Today’s real world example is slightly different than a usual example.  I was given an opportunity to perform an IME on a patient in a MVC.  He was in significant pain, but didn’t have any objective evidence of injury.  He did not have any disc damage on MRI and no ligament damage seen on the x-rays.  He did have some positive orthopedic tests and a decrease in range of motion. 

This patient was sent to physical therapy chiropractic care and eventually pain management.  The pain management doctor gave him a diagnostic lidocaine injection for facet pain.  This injection took all of the patient’s pain away for 2-3 months.  The pain management doctor used this as justification of give him ongoing steroid injections to manage his facet joint pain. 

Treatment went on like this for over a year with 3 steroid injections prior to my IME.  Each injection seemed to help him less and the patient was frustrated with his pain.  The insurance adjuster hired an IME doctor prior to my IME and I was able to review this report.  The insurance IME doctor stated that the patient did not likely have any injuries, but was malingering or faking an injury.   The justification was that the lidocaine injection was a diagnostic tool that should have decreased symptoms for hours not 2 months. 

It is difficult to say why the lidocaine injection helped for 2 months.  It could be malingering or perhaps a placebo.  In my experience most patient’s show no signs of malingering, but I am sure this happens.  I feel like the problem with this case is that the doctor went ahead with steroid injections after the patient had such strange results to the diagnostic testing.  The other problem I see is that this patient’s attorney was okay allowing 3 steroid injections to be done on a lien with minimal justification for the treatment. 

I know that it is not the attorney’s job to dictate treatment.  However, I feel like it is the attorney’s job to understand enough of the care given to patient to see red flags in the case.  In this case the attorney was just happy the patient had a lot of treatment from a medical provider and that the bills were getting higher. 

After my IME the attorney was able to get the case settled, but not for nearly as high as the attorney and patient were thinking.  The insurance company refused to pay for the 3 steroid injections and future steroid injections.  I did not include future steroid injections as future care he might need in my report.