Research has demonstrated that many individuals with Crohnâs ileitis share a genetic mutation that may play a significant role in disease development. A hypersensitive immuno-response to a pathogenic presence, such as bacteria, within the gastrointestinal tract is also suspected of contributing to the disease's onset.
Secondary osteoarthritis occurs less frequently than primary (also known as idiopathic) osteoarthritis. Primary osteoarthritis means that there is no known cause for the joint breakdown.
When the cartilage deteriorates (degenerates), the bone next to it becomes inflamed and can be stimulated to produce new bone in the form of a local bony protrusion, called a spur.. A very common early sign of osteoarthritis is a knobby bony deformity at the smallest joint of the end of the fingers.