Oh boy. Let’s talk chiropractic. This might get a little technical and I will not be able to resist the temptation to use some big words, but don’t worry, you’re smart. You can handle it.
First, I want to quickly discuss a few things that a subluxation is not and why there is so much confusion surrounding this one word.
A Medical Subluxation is basically one step bellow a full dislocation. A complete dislocation occurs when two joint surfaces are no longer in contact. A medical subluxation is when there is a drastic displacement of those two joint surfaces, but there is still some contact between the two, so it is not a full dislocation. The shoulder and joints of the clavicle (collar bone) are common sites of this sort of distortion. Although we are trained in relocating true dislocations, this is NOT what chiropractors are talking about when we refer to a subluxation.
A true Pinched Nerve occurs when degenerative changes of the bone (usually the vertebrae) progress to the point of putting physical pressure on a spinal nerve. Typically, it is in the form of stenosis (narrowing of a space or tunnel through which the nerve travels) or osteophytes (sharp beak-like projections that grow from the bone seen in osteoarthritis/degenerative joint disease). This is a bad situation to be in! When a bony growth is putting pressure on a nerve, the only sure-fire solution is to go in there with a knife and scrape it down. This true pinched nerve is often confused with many other peripheral neuropathies that are considerably less serious.
The subluxation that chiropractors are obsessed with is something much cooler. We are taking about the Vertebral Subluxation Complex (VSC).
What is a Vertebral Subluxation Complex?
A Vertebral Subluxation Complex (VSC) is a complex and intricate neuro-musculo-skeletal phenomenon (meaning it involves nerves, muscles, and bones). It presents as a loss of juxtaposition. Juxtaposition is the relationship between two joint surfaces. Joint surfaces may still be in close proximity (as in, not dislocated or medically subluxated), but not situated in proper, functional alignment with each other. It’s an issue of joint centration. This has implications on the ability of the joint to communicate properly with the brain, the reflex reactions of the surrounding muscles, and the capacity of that joint to move fluidly throughout its full range of motion. That’s just the beginning.
The loss of juxtaposition typically results in a restriction along one or more planes of joint motion and altered nervous system function away from and to that joint. The resultant dysfunction can be classified under 5 categories of pathology:
o A dysfunction in joint movement. It may be either hypermobile (as in instability) or hypomobile (as in restriction).
o The physical and neurological disruption of the VSC can have either compressive or facilitative effects on the nervous system, causing neurological dysfunction. Again, we are talking too much or too little here. The autonomic nervous system relies on a Goldilocks balance of Parasympathetic and Sympathetic activity, upon which the VSC can be a major disruption.
o Myo means muscle. Surrounding the joint, you can have hypotonic (low tone) or hypertonic (high tone) muscles. High tone makes you feel tight and restricted, whereas low tone can make you feel loose and unstable. Neither are just right and both affect joint motion and nervous system communication, especially when dealing with postural muscles.
o Histology deals with the chemistry on the nitty-gritty cellular level. Swelling, inflammation, immune system disturbances, and any changes on the cellular level are all noted here. Degenerative histological changes are noted at the joint within 4 weeks of restricted movement, regardless of age.
o This is where you end up down the road if you did not listen to the signals that your body was giving you in the categories above. Chronic neuro-musculo-skeletal dysfunction of the spine affects your whole health. When not cared for, this can result in degenerative changes and system dysfunctions. Now you have entered the realm of clinical disorder and disease.
How does all that happen from one tiny little joint boo-boo?
Optimal, dynamic joint position is maintained by muscles, tendons, ligaments, joint capsules, and osseous structures of the vertebra, all regulated by the nervous system. Sensory receptors in the joint capsule and surrounding tissues send kinesthetic (movement and position) information to the brain. The brain compares the information that it receives from the joint about what is going on with what it knows should be going on. If there is any incongruence with what is and what should be happening at the joint, local stretch reflexes offering sensory information will cause a muscular response in attempt to restore proper joint position. This stretch reflex is essential for normal tone and balance of spinal/postural muscles.
When a VSC occurs, kinesthetic/proprioceptive receptors relay faulty sensory information up the spinal cord to the brain. The brain says “What the heck are you doing down there!?!” and instantly send a response. Your body attempts to correct the VSC by subtly (or not so subtly) increasing the tone of specific spinal muscles to restore and maintain proper juxtaposition.
Sometimes, the load is too much for our super smart body to handle. We are not able to gracefully adapt. This might be because of exuberant chemical, physical, and/or emotional stresses that your body is dealing with on a regular basis. This allostatic load affects your body’s ability to adapt, respond, heal, and grow. On the physical end, it includes repetitive microtraumas (such as always holding baby on your right hip or sitting in a chair at desk all day) or macrotraumas (like an epic tobogganing wipeout or motor vehicle accident). Chemical environment and emotional traumas and stressors are just as powerful and share an equal burden on your body as the physical insults.
So, all of this put together: Minor faulty shifts in juxtaposition (we’re talking the width of a dime here) caused by major or minor physical, chemical, or emotional stresses cause an adaptive response in your body. This disruption has structural, functional, histological, and neurological consequences that do not allow your body to express its full potential of health and vitality.
Why the confusion?
About 100 years ago, we really did used to think that it was a “bone out of place” (known as a BOOP) putting direct pressure on a nerve because that was the most logical conclusion based on the knowledge and understanding of the human body at that time. We have a much more complex and sophisticated understanding of the human body now, especially with regards to the nervous system. So why do some chiropractors still explain it this way? They do it because it is easy to understand without going to school to study anatomy for a decade.
But I know you’re smart. You can handle this sophisticated knowledge and having a more complete understanding how your body works will empower you to make good decisions for your optimal health and awesomeness.