Intervertebral Joint Definition and Spinal Pain Types

Spinal column
Spinal column. Science Picture Co./Collection Mix: Subjects/Getty Images

Intervertebral Joint Definition

The intervertebral joint comprises the functional unit of two adjacent vertebrae.  These units facilitate movement of the spine. Surgeons, doctors, spine specialists and biomechanic specialists refer to an intervertebral join aa  "motion segment."

The meeting points of the two spinal bones involved in forming an intervertebral joint are the vertebral body (the front portion) and the vertebral arch (the back portion). Between the vertebral bodies, cushioning is provided by the presence of intervertebral discs. Between the vertebral arches, the movement is facilitated and constrained by small facet joints.

The intervertebral disc is often the site of pain, and a number of conditions may prevail there.  Some, like herniated disc, are generally due to injury, while others, like degenerative disc disease, tend to be related to the aging process.  

Learn more about the various types of disc pain: 3 Ways Your Discs may Be Causing You Pain

Movement in all directions (forward, back, side to side and twisting) occurs at the many intervertebral joints in the spine.  Ligaments made of tough fibrous bands of connective tissue help stabilize the intervertebral joints during movement and support the column during weight bearing.  Other joints known as facets, located at the back of the column, help stabilize the spine, as well.

Spinal Fusion and the Intervertebral Joint

Spinal fusion surgery, as the name suggests, is a procedure that fuses two or more intervertebral joints together.  Sometimes fusions are done along with a discectomy, while at other times the discectomy is given alone. 

Spinal fusion is often performed on more than one "motion segment," i.e. more than one intervertebral joint is fused.  Scoliosis surgery is a good example of this (though certainly not the only.)  The purpose of scoliosis surgery is to reduce the degree of rotation in a series of adjacent vertebrae.

Among the many types of spine surgery, spinal fusion is the most commonly given - and in particular, lumbar (low back) fusion. It is so prevalent,  In fact, the researchers have taken up the task of evaluating its effectiveness.  Some conclude that this surgery is given when and where it is not necessary, and does not always lead to pain relief and/or improved physical functioning in patients.

For example, Rick Deyo, et. al. in their study, "Overtreating chronic back pain: time to back off?" which was published in the January - February issue of the Journal of the American Board of Family Medicine report on four randomized clinical trials that found spinal fusion for degenerative disc disease with no sciatica yielded limited benefit.  

The authors comment the even though there was no real reason why more spinal fusions should be done, their use skyrocketed 220% between the years of 1990 and 2001 in the United States. They say this rise accelerated in 1996, when the fusion cage, which was a new type of instrumentation at that time, was approved by the FDA.

The researchers surmise that this FDA approval underlies the increase in procedures. 

And finally the authors say that during this time, Medicare claims for spinal surgery went up by 40%, with a 70% increase in overall spinal fusion surgery rates, and 100% in implants (such as the fusion cage.)


View Article Sources
  • Deyo, R.A., Mirza, S.K., Turner, J.A., Martin, B.I. Overtreating chronic back pain: time to back off? J Am Board Fam Med. Jan - Feb 2009.