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.
Primary OA, often as part of generalised OA, is rarely commented on in textbooks, but is seen reasonably frequently in practice, especially in the TMT joints. Osteoarthritis may also occur in association with tarsal coalitions.