Updated: May 4
Did you know that up to 85% of the population will experience low back pain throughout their lifetime (1). In fact, back pain is the second-leading reason that patients seek out the help of their medical practitioner.
A large percentage of this back pain is associated with the degenerative changes that take place in the spinal discs. The majority of the population has some degree of disc degeneration or Degenerative Disc Disease (DDD). DDD is a type of osteoarthritis of the spine.
Degenerative Disc Disease can occur at any location in the spine but is most common in the neck (cervical region) and the low back (lumbar region).
Healthy discs normally act as shock absorbers. Once the spinal discs start to degenerate there will be an immediate reduction in the discs shock absorption capacity.
This decreased capacity can have several severe consequences, such as:
Facet joint degeneration (osteoarthritis).
Spinal pain, stiffness, and dysfunction.
Bone spur formation.
Degeneration of the vertebral body (end plates), which intern causes increased pressure on the spinal nerve roots (nerves that exit from the spinal cord). This can eventually cause radiating pain down the arms or legs (sciatica type pain).
More About Your Intervertebral Discs
It’s worth taking a minute to understand the important role that your intervertebral discs play in your daily motions and activities.
The intervertebral discs (fibro-cartilaginous cushions) make up to one-quarter of the spinal column's length, and function as the spine's shock absorption system. Intervertebral discs are designed to:
Absorb a huge amount of stress.
Act as a hinge, permitting increased range of motion and mobility in the spine.
Protect the spinal cord and its nerve roots.
The discs lie between, and are attached to, the vertebrae of the backbone. They form part of the front wall of the spinal canal.
The discs are made up of two primary layers:
Annulus Fibrosus – This forms the outer edge of the disc and is a strong spherical structure made up of sheets of collagen fibres that are connected to the vertebral end plates (end of the vertebral bodies).
Nucleus Pulposus – Which forms the centre of the disc and is a gel-like material that is able to resist great compressive forces.
Since these intervertebral discs DO NOT have a direct blood supply, they are dependent on the end-plates of the vertebral bodies to circulate essential nutrients. Any problems that cause a decrease in the normal exchange of fluids within this area can lead to a host of degenerative conditions.
WHAT IS DEGENERATIVE DISC DISEASE?
Disc degeneration: It is very interesting to note that what occurs during normal aging to spinal discs is not that same as degenerative disc disease (DDD). Normal aging and DDD are different biological events!
Let's review some of the major differences between normal aging and DDD in relationship to the intervertebral discs of the lumbar spine.
This recent information comes from RRS education (Dr. Shawn Thistle), Dr. Thistle, the founder of RRS education, teaches seminars covering the latest research on a wide variety of musculoskeletal topics. I highly recommend you attend one of his seminars if you are a practitioner.
The hallmarks of normal aging of the intervertebral discs include:
NO decrease in the intervertebral disc height.
A decrease in the water content in the vertebral disc, in facet there is considerable dehydration by age 40.
Fiber orientation of the disc that becomes irregular, with the formation of fissures.
An aging process that occurs from the inside out.
The hallmarks of the degenerative disc disease in the intervertebral discs include:
A considerable decrease in the intervertebral disc height, which decreased the disc's ability to absorb shock.
Pathological changes in the vertebral endplates. When these endplate changes are observed it is a definitive indication that DDD is present.
Changes from the outside in, not from the outside in out as with normal aging.
Discs that become very stiff/weakened, and have an impaired load bearing capacity.
Fissures and tears occur on the outside of the disc (Annulus Fibrous) moving inward, this enables in growth of nerves and blood vessels. This ingrowth creates generators of pain.
Discs that when loaded lose fluid quicker than aging discs, consequently they lose disc height, and have a decreased ability to bear loads.
Note: Cervical Disc Degeneration is common. In the 2015 study (Nakashima et al 2015) 1211 healthy volunteers between the ages of 20 to 70 were examined by MRI for cervical disc degeneration. The results showed that 90% of those examined had bulging discs. What was interesting was that 75% of those in their 20's also had disc bulges. Most people never consider that someone in there 20's could have damage to their vertebral discs.
MANAGEMENT OF DEGENERATIVE DISC DISEASE
Many of our patients do not realize that they have non-surgical options for treating Degenerative Disc Disease (DDD).
Though it is true that no one can turn back the clock and completely reverse the degeneration, there is still a considerable amount that can be done.
A combination of manual therapy and exercise can - in the majority of cases improve the patient's quality of life while alleviating the suffering they are experiencing.
There are three primary objectives that we try to address when treating DDD:
Improvement of joint mobility.
Reduction of pain and stiffness.
Inhibition of the progression of further joint damage.
Interestingly, research is showing that (over the long term) a combination of manual therapy and exercise is just as effective as surgery (surgical spinal fusion) at reducing pain and disability for patients who suffer from DDD (2).
MANUAL THERAPY CAN BE VERY EFFECTIVE
There are two aspects of treating DDD with manual therapy that must be addressed to achieve optimal results. The first is addressing joint mobility and the second is tissue quality.
Research has shown us that when joints become immobile, due to injury or osteoarthritis, they then become subject to several physiological changes such as:
Decreases in fluid content, which causes a decrease in the joint-fiber distance within the capsule surrounding the joint.
Increased adhesion formation in the synovial folds of the joints. Which can cascade into tissue failure, even with diminished tissue loading. (1, 2)