Are degenerative changes on x-rays always indications of an old injury?

I think in a lot of ways forensic health care can be summed up in showing objective evidence of an injury with causation.  There a lot of different ways to do this.  Unfortunately, there is rarely a 100% way to show causation.  My last podcast I shared a real life example of a patient with a 100% certainty what caused his injury.  As a refresher he had hot antifreeze spill on him while at work causing very significant burns.  This case is by far the exception and most injury cases will be much more difficult showing causation.  In the state of Utah causation has to be more likely than not the injury is 51% responsible for the damage.  Other jurisdictions have different definitions of causation.  

A lot of my podcasts I used the analogy of painting a picture.  If we take all available evidence we can start to put a picture together.  Does the picture show a lot of pre-existing degenerative changes with a significant past medical history. Or does the picture show new damage with no pre-existing degenerative changes and no past medical problems? 

Today’s study discusses degenerative changes in the cervical spine seen on x-rays.  This study is The Diagnostic Value of an X‐ray‐based Scoring System for Degeneration of the Cervical Spine: A Reproducibility and Validation Study  by Maarten VanErd et al published in the Pain Practice Journal 2021.  We talked about degenerative changes seen on imaging in prior podcasts.  Most notably podcast 6 which was about Wolff’s Law. 

These degenerative changes come from altered biomechanics.  Once there is damage to a joint significant enough to alter the mechanics of the joint there will be degenerative boney changes.  The altered mechanics of a joint place different stresses on bones which causes the bones to adapt and grow boney osteophyte changes.  We discussed the Gone He study from 2006 that showed degenerative changes take a minimum of 6 months to be seen on imaging. 

6 months after an injury there will only be the start of these osteophytes or boney degenerative changes.  Most boney degenerative changes take years to develop.  This information can help us understand an aspect of causation.  Just because a patient has degenerative boney changes doesn’t mean they do not or cannot have a new injury.  It is once part of the entire picture showing that there were definitely problems of some sort prior to the injury.    

This study aimed to develop a reproducible and clinically feasible diagnostic system to assess for degeneration on cervical x-rays.  This study addressed the fact that with degenerative conditions and even diagnostic blocks we can determine the source of pain, but not the cause of pain.  This is very important to understand.  With x-rays we can often see sources of pain, but that doesn’t mean the cause.  If we see significant degenerative facet joints it is likely that the patient has facet mediated pain.  This is often then tested with diagnostic blocks.  If the diagnostic block takes the pain away then the patient clearly has facet joint pain.  However, as stated in this article the facets may not be the cause of the pain. 

Often the cause of facet pain and facet degenerative changes is secondary to ligament damage or disc damage.  Ligament and disc damage will permanently alter the biomechanics of the spine leading to the facet degenerative changes.  This is a very important distinction to make.   This study went on to show quote “Asymptomatic patients may have degenerative abnormalities and patients with pain may show only minor degenerative changes, indicating the complexity of neck pain” end quote”. 

As for forensic health care today’s study is helpful at standardizing what type of findings on x-rays of the cervical spine show degenerative changes.  These degenerative changes or lack of degenerative changes can help paint a picture of causation. 

The problem with x-rays is there can be different opinions depending on who is writing a report.  A 2009 study published in the Spine Journal by JD Lurie et al. showed that 42.2% of radiologist misread the description of disc damage.  I see this all the time that one radiologist will report one thing and another will not.  This happens in court all the time that both defense and plaintiff will make different arguments based on the same imaging.   

That is why this study came out.  Find a standardized way to assess if the cervical x-rays show degenerative changes and make it reproducible between different doctors.  They came up with 6 different indications of degenerative changes including: cervical disc height loss, anterior vertebral osteophytes, posterior vertebral osteophytes, vertebral end plate sclerosis, facet joint osteoarthritis and uncovertebral osteoarthritis.  Facet joint osteoarthritis was taken out of the study.  The facet joints overlap on the lateral cervical x-rays making it difficult to assess.    

I will go over the ways they used to assess these 5 indications of degenerative changes.  The agreement between the different doctors assessing these 5 indications of degenerative changes was quote “near perfect” end quote. If we follow the way they assessed these cervical spine x-rays we should get less disagreement on imaging from different providers. 

The first is loss of disc height.  They measured the disc height in the middle of the 2 vertebral bodies.  They then measured the posterior side of the vertebral body of the level below.  If the height of the vertebra is more than 3 times taller than the disc then there is disc height loss. 

The measurement for anterior osteophytes a line is drawn along the middle section of the anterior vertebral body to the superior and inferior endplate.  If the vertebra has boney outgrowth that go beyond the anterior line, then there are degenerative anterior osteophytes.

The measurement for posterior osteophytes is similar to anterior.  A line is drawn in the middle of the vertebrae and if there is boney outgrowth beyond this line then there are posterior osteophytes. 

Vertebral end plate sclerosis is degenerative changes on the top of bottom of the vertebra.  An endplate is the top of bottom of the vertebra and sclerosis is hardening or boney growth.  This is seen with broader whiter and or more irregular aspects of the endplates. 

Uncovertebral osteoarthritis is measured on the AP view.  A normal uncovertebral joint is cup-shaped configuration.  A degenerative uncovertebral osteoarthritis will show a laterally deflected shape resulting in a soup plate shape. 

This study showed that if we use these methods, we can have great inter doctor reliability assessing the presence or absence of degenerative changes in the cervical spine on x-rays.  They reported that if there are 3 out of these 5 degenerative changes seen there is likely facet joint pain.

Real world example

I was at a deposition a few years ago for a 30-year-old patient in a motor vehicle collision.  This patient had no prior injuries and no past medical history of neck pain.  The patient failed to make progress with care and cervical flexion and extension x-rays were ordered.  These x-rays showed she had significant ligament damage, alteration of motion segment integrity or AOMSI. 

The defense had an expert review the x-rays and claimed there was no signs of ligament damage, but did show signs of degenerative changes.  Their expert reported that all findings showed old problems and nothing new.  Of course, the defense expert did not do any measurements showing no AOMSI or ligament damage.  The defense expert did not even make any remarks about my measurements and findings of AOMSI. 

In the deposition I was asked why my x-ray report did not mention any of the degenerative changes reported by the defense expert.  I reported that I did not see any degenerative changes on the x-rays.  The lawyer asked me how it was possible that I couldn’t see what their expert saw.  I was able to explain in the deposition that it can be common for different doctors to different opinions of imaging.   The lawyer then asked how do we know who is correct.  I was able to explain that every health care provider is allowed to have an opinion.  I was then able to explain that my assessment of her cervical spine x-rays was based upon the article we covered in today’s podcast. 

I was able to show that research has been done to assess when degenerative changes are present with near perfect reproducibility between different doctors.  I then went on to show that there are 5 different aspects to look at on the x-rays and methods of how to assess them.  I then reported that I would be happy to pull the x-rays up and the study.  At this point the attorney changed topics and never came back to the x-rays and degenerative changes. 

This case was eventually settled and never went to court.  I know that the defense attorney was scared to have an argument in court that their expert claimed the patient had degenerative changes and no ligament damage, but had no way to show either of these things.  I would have been able to show on the x-rays that there were clearly no degenerative changes and that all the measurements showed that according to the literature that in fact there was catastrophic or sudden and complete ligament damage in her cervical spine.   

This was just one example of how I have been able to show there is or is not degenerative changes in the cervical spine based not on only my opinion, but by a standardized method. 

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