As the cervical spine degenerates with age, other changes also take place in the neck. As the cervical spine begins to experience hypermobility (excessive motion) due to disc and joint degeneration, the neck’s bony structures and soft tissues try to adapt in an attempt to heal and stabilize the joints.
In some cases, these changes to muscles and bones in the cervical spine may also lead to pain, ranging anywhere from a dull ache that is felt sporadically to shock-like pain and neurological symptoms that are persistent and possibly radiate down the arm, such as pins-and-needles tingling, numbness, and/or weakness.
Cervical Bone Spur Formation
When the cervical spine’s stability is reduced because of weakened discs, facet joints, ligaments, and/or tendons, there is a greater likelihood for bones to rub together. If bone starts to grind against bone—such as when two vertebral bodies are no longer fully cushioned by the disc between them or when cartilage wears down between two articular processes—bone spurs (osteophytes) begin to grow in an attempt to enlarge and stabilize the joint.
Muscle Spasms to Protect the Neck
As the cervical spine’s degenerative process progresses, one or more of the surrounding muscles in the neck and upper back could become more susceptible to going into a painful spasm. A few different ways this could happen include:
- Overworked or overstretched muscle. If the cervical spine’s degenerative changes cause posture to worsen and the head to drift further and further in front of the shoulders, muscles that support the head and neck can become elongated, weakened, and forced to work too hard. In this situation, the muscle may spasm and tighten up.
- Reaction to nearby inflammation. If inflammation is present from a nearby spinal joint, such as a degenerating facet joint or herniated disc, the muscle could potentially go into spasm in an effort to protect itself from the inflammatory agents.
There could be other reasons for a muscle spasm to occur in the neck, and sometimes the specific cause of a muscle spasm cannot be identified.
Ligamentum Flava Thickening
The ligamentum flava are a pair of ligaments that connect the laminae (bony vertebral arches) of adjacent vertebrae. When healthy, the relatively strong, elastic ligamentum flava help the neck maintain posture and bring the vertebral arches back into neutral position after flexing forward.
Due to their location at the back of the spinal canal and attachment to part of the facet joint’s capsule, degenerative changes to the ligamentum flava can become problematic for nearby structures. For example, a degenerating ligamentum flava could push into the spinal canal and compress the spinal cord, or push into the foramina and compress the nerve root.
While it is known that the ligamentum flava degenerate and lose elasticity over time, there are competing theories regarding how and why. For example, one recent study suggests that inflammation from nearby degenerating facet joints can cause degenerative changes in the ligamentum flava.1 However, there is still debate regarding whether the ligamentum flava truly thicken (get physically bigger) or if perhaps they simply buckle more into places they previously did not.2
Scarring Increases Stiffness, Decreases Performance
When muscles, ligaments, or tendons in the cervical spine experience tears—even small ones—scar tissue is formed in an attempt to heal the tissue and maintain function. When scar tissue starts to build up, muscles can become weaker and tighter, and tendons and ligaments can become less elastic.
Scar tissue can also build up in the joint capsule, synovium lining, discs, veins, and nerves that become injured or stressed due to spinal degeneration. While the scar tissue serves a healing purpose, these structures can still experience reduced flexibility and functionality as more scar tissue builds up.