A bone spur, also called an osteophyte, is an abnormal growth of bone on top of normal bone. Although it is called a spur, a bone spur is not sharp. It is actually smooth to the touch. But because a bone spur grows on top of normal bone where it doesn’t belong, it can press on other bones as well as on ligaments, tendons, and nerves, wearing them down and causing pain. One of the most common places for a bone spur to occur is on the spine.

Bone spurs are usually caused by a disease or condition that results in degeneration of the vertebrae and cartilage in your spine. The extra bone that grows and forms the bone spur is your body’s way of trying to heal the affected area. Often the degeneration that causes bone spurs to form are the result of the normal aging process. As you get older, the cartilage that covers the ends of the vertebrae that make up your spine wears down. This process is called osteoarthritis.

As the discs between your vertebrae wear out from normal wear and tear – a process called degenerative disc disease–this may also cause bone spurs to form. In middle-aged and older people, degenerative disc disease can cause bone spurs to form around the nerve roots. This usually occurs inside the foramen , which is the opening in the spine where the nerve roots leave your spine to travel to other parts of your body. If these bone spurs get large enough, they may begin to rub on the nerve root and irritate it.

Diffuse idiopathic skeletal hyperostosis (DISH) is a condition that can cause bone spurs to form on the ligaments of your spine.

Bone spurs can also develop in older people who do not have another condition affecting their spine.

Bone spurs can also lead to other spinal conditions such as:

• Spondylosis – a condition in which osteoarthritis and bone spurs cause degeneration of the vertebrae in your cervical spine (neck) or lumbar spine (low back)
• Spinal stenosis – a condition in which bone spurs cause narrowing of the spinal canal, which puts pressure on your spinal cord