Intervertebral discs are like cushions between the individual vertebrae. They have a soft centre (nucleus pulposus) surrounded by a tough outer ring of fibrocartilage (annulus fibrosus).
With age and injuries, the gel-like discs lose their water content and shrink, thus reducing their shock-absorbing and stabilising properties. This increases the stress on the joints and ligaments.
Over time, the cartilage in the joints becomes thinner, and overgrowth of bone occurs leading to the formation of spurs (osteophytes). The ligaments also become less elastic and thicken with age, leading to stiffness and loss of stability.
Spondylosis usually occurs after the age of 40 years, although it may occur earlier due to factors such as:
