A disc Protrusion may cause muscle spasm, pain, numbness, or weakness, when the intervertebral disc protrudes into the nerve root exiting the spine through the intervertebral foramen.
You may think of a disc protrusion as a milder form of a degenerative process known as a herniated disc. As patients age, their inner nucleus (nucleus pulposus) may begin to lose its water density, and the outer portion of the disc's envelope may begin to wear out. So the disc begins to collapse because of the drying out of its interior, while its outer wall (annulus fibrosus) becomes worn out and prone to tearing from the inside out. If the intervertebral's outer wall manages to wear out while the disc still has a relatively high concentration of fluid, the pressure exerted upon it may make it prone to tearing from the inside out, or bulging outwards at the portion of the wall that has become narrow. If tears of this outer wall opens up that are large enough to let material from the nucleus to become ejected, the condition is known as a herniated disc. If the walls become narrow while there is still enough water on the inside of the disc to exert a significant amount of pressure, the condition is known as a bulging disc, or disc protrusion.
Both a disc protrusion and a herniated disc can cause back pain, as well as related symptoms such as numbness, burning, sharp pain, and weakness of affected extremities (i.e. arms and legs) - in the same way. Any degenerative changes to the disc may cause back pain and related symptoms if it causes the adjacent nerve roots exiting the spine through the intervertebral foramen to become pressed upon. With a disc protrusion, the wall of the disc may bulge outwards, invading the space near the spinal nerve root and eventually pressing upon it. This pressing of the bulging disc into the nerve root, is why the condition is also sometimes known as a pinched nerve. The nerve may also become pinched if the material oozing out of the disc, as a result of a herniated disc, moves into and presses into the adjacent nerve. The symptoms associated with a pinched nerve may vary from disruptive pain to more severe effects such as atrophy of the muscles that that nerve supplied. Hopefully, a patient will have sought out medical treatments far before symptoms such as atrophy of the muscles or even failure of conscious movement of the involved skeletal muscles occur.
We may feel pain and other assorted symptoms, as a result of a disc protrusion, if the bulging wall of the intervertebral disc comes in contact with the ligament or nerve root. If this push, or bulge, is exerts enough force to impair motor functioning, than the patient may experience significant sensory loss or loss of strength in the muscles and limbs that supply are supplied by that nerve. The disc protrusion may also be said to irritate that nerve, and cause less severe symptoms, such as mild to moderate back pain, or slight numbness/tingling in the body section supplied by that nerve. If the spinal ligaments are impacted by bulging or herniated discs, the patient may also feel pain as a result of this condition. Either bulges or herniations of the discs may also cause painful, protective muscle spasm, called secondary muscle spasm.