The spinal discs are fibrous pads that are in between the vertebrae. There is a jelly portion in the middle...kind of like a jelly donut. This is what gives the spine flexibility.
Cervical spinal discs are very strong...they need to be because they were designed to act like shock absorbers. The spinal discs also hold the spinal bones together...so they are considered a ligament.
When the cervical discs degenerate the bones come closer together because the disc loses height. This can actually irritate the cervical nerve roots and cause neck pain, pain in the arm and hand, and weakness of grip...along with a bunch of other stuff...including headaches.
And...the degenerative process can be happening for quite a while without any symptoms.
I have been treating DDD and herniated discs now for 17 years in the SF Financial District. One thing is clear...once you know you have disc degeneration in the neck, it's best to take action and try to contain the damage and slow down the progression of the disease process. This is where chiropractic comes in.