There is a lot of nomenclature for intervertebral disc injuries in the spine. Slipped disc, bulging disc, and herniated disc are the most common terms that patients will tell me. If injured, discs can be very painful, but research has shown the opposite is true too. If you have an injured disc you may not have any symptoms.
What are intervertebral discs?
For a quick anatomy lesson, intervertebral discs are the fibrocartilaginous material that sit between the vertebrae in the spine. They act as a “cushion” or “shock absorber” for the spine. The disc is formed of an inner nucleus pulposus and an outer annulus fibrosus layer. The nucleus pulposus is a jelly-like substance, and the annulus fibrosus is an overlapping fibrous ring structure surrounding it. The disc structure attaches to a cartilaginous end plate on the vertebral bodies.
What is the clinical significance of intervertebral discs?
There are three common types of injuries to the intervertebral discs; bulging discs, herniated discs, and degenerative discs.
- Bulging discs is when a disc extends past the normal boundaries of the vertebral bodies.
- Herniated discs come in three types: protrusions, extrusions and sequestrations. Disc herniations have the potential to put pressure on the surrounding structures and cause pinched nerves or in severe cases a pinched spinal cord.
- Protrusions are when the nucleus pulposus pushes out into the annulus fibrosis but does not break the outer barrier.
- Extrusions are when the nucleus pulposus pushes out into the annulus fibrosus and breaks the outer wall.
- Sequestrations are when the nucleus pulposus completely is ejected out of the disc.
- Disc degeneration is the natural occurrence of the disc to lose height and water content as we age. Certain traumas or behaviors could speed up the process. Less height and less water content leads to joint stiffness and susceptibility to more injury since there is less force absorption.
Do disc injuries cause pain?
The problem is that there have been studies done via MRI on people without pain, that show disc injuries. So, the real question is can they cause pain? Yes, disc injuries can cause significant pain, and can cause other symptoms when they press on surrounding nerves. Yet they do not always cause pain. Chiropractic care, physiotherapy, and other allopathic treatments can reduce your pain and make you feel normal, but you may still have a disc injury. If you’ve been diagnosed with a disc injury, it is important to follow your providers advice on home care, lifting properly, ergonomics, and continued exercise.