|Small marginal osteophytes (arrows) of the processus anconeus of the ulna can be seen in this gross pathological specimen of a sow.|
|Classification and external resources|
Osteophytes are exostoses (bony projections) that form along joint margins. They should not be confused with enthesophytes, which are bony projections that form at the attachment of a tendon or ligament. Osteophytes are not always distinguished from exostoses in any definite way, although in many cases there are a number of differences. Osteophytes are typically intra-articular (within the joint capsule).
Osteophyte formation has been classically related to any sequential and consequential changes in bone formation that is due to aging, degeneration, mechanical instability, and disease (such as diffuse idiopathic skeletal hyperostosis). Often osteophytes form in osteoarthritic joints as a result of damage and wear from inflammation. Calcification and new bone formation can also occur in response to mechanical damage in joints.
Osteophytes form naturally on the back of the spine as a person ages and are a sign of degeneration in the spine. In this case, the osteophytes are not the source of back pains, but instead are the common symptom of a deeper problem. However, osteophytes on the spine can impinge on nerves that 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 because the nerves are supplying sensation to their dermatomes. 
Normally, asymptomatic cases are not treated. Non-steroidal anti inflammatory drugs and surgery are two typical options for cases requiring treatment.
- "osteophyte" at Dorland's Medical Dictionary
- Rogers J, Shepstone L, Dieppe P (Feb 1997). "Bone formers: osteophyte and enthesophyte formation are positively associated". Annals of the Rheumatic Diseases. 56 (2): 85–90. doi:10.1136/ard.56.2.85. PMC . PMID 9068279.
- "The Medico-chirurgical Review and Journal of Medical Science". Burgess and Hill. 1 January 1844.
- Alonge TO, Rooney P, Oni OO (2005). "The ultrastructure of the peri-articular osteophytes - an evaluation by scanning electron microscopy". West Afr J Med. 24 (2): 147–50. PMID 16092317.
- Nathan M, Pope MH, Grobler LJ (Aug 1994). "Osteophyte formation in the vertebral column: a review of the etiologic factors--Part II". Contemporary Orthopaedics. 29 (2): 113–9. PMID 10150240.
- Bone spurs MayoClinic.com
- Mayo Clinic website concise information on bone spurs