Bone spur

Overview
Bone spurs, also known as osteophytes, are bony projections that form along joints. Bone spurs form due to the body's increase of a damaged joint's surface area; most commonly from the onset of arthritis. Bone spurs usually limit joint movement and typically cause pain.

Bone spurs form naturally on the back of spine as a person ages and are a sign of degeneration in the spine. In this case the spurs are not the source of back pains, but instead are the common symptom of a deeper problem. However, bone spurs on the spine can impinge on nerves, which leave the spine for other parts of the body. This impingement can cause pain in both upper and lower limbs and a numbness or tingling sensations in the hands and feet due to the nerves supplying sensation to their dermatomes.

Spurs can also appear on the feet, either along toes or the heel, and can also occur on the hands. In extreme cases it has been known for these spurs to grow along a person's entire skeletal structure, along the knees, hips, shoulders, ribs, arms and ankles. Such cases are only exhibited with multiple exostosis.

Osteophytes on the fingers or toes are known as Heberden's nodes (if on the DIP joint) or Bouchard's nodes (if on the PIP joints).

Bone spurs may also be the end result of certain disease processes. Osteomyelitis, a bone infection, may leave the adjacent bone with a spur formation. Charcot foot, the neuropathic breakdown of the feet seen primarily in diabetics, will also leave bone spurs which may then become symptomatic.

Cause
Osteophyte formation has been classically related to any sequential and consequential changes in bone formation due to aging, degeneration, mechanical instability, and disease. Often osteophytes form in osteoarthritic joints due to damage and wear from inflammation. Calcification and new bone formation can also occur in response to mechanical damage in joints, or at the attachment points for ligaments and tendons.

Osteofyt