There are differences between degenerative (age-related, wear), inflammatory (joint degeneration by inflammatory arthritic desease, see below), traumatic (fracture, muscle or legement rupture) and posttraumatic disorders (joint incongruencies after healed fractures or bone necrosis, see below) of a joint. They all end in a joint incongruency, affecting daily painfree use.
OSTEOARTHRITIS : this is an age-related “wear and tear” type of arthritis. It usually occurs in people 50 years of age and older, but may occur in younger people, too. The cartilage that cushions the bones wears away and the bones then rub against each other. Over time, the joint slowly becomes stiff and painful. Unfortunately, there is no way today to prevent the development of osteoarthritis. It is a common reason people undergo joint replacement surgery. Osteoarthritis may also be caused or accelerated by subtle irregularities in how the joint developed in childhood.
RHEUMATOID ARTHRITIS : this is a disease in which the synovial membrane that surrounds the joint becomes inflammated and thickened. This is an autoimmune process that can damage the cartilage and eventually cause cartilage loss, pain, and stiffness. Rheumatoid arthritis is the most common form of a group of disorders termed “inflammatory arthritis".
POST-TRAUMATIC ARTHRITIS : this can follow a serious joint injury like fractures and / or muscle/legamentous tears. Fractures of the bones that make up the joints may damage the articular cartilage over time resulting in joint incongruency followed by degeneration of the cartilage because of eccentric wear. This can causes pain and limited joint function.
Special knee joint pathologies
POST-TRAUMATIC ARTHRITIS : post-traumatic arthritis can develop after an injury to the knee not only because of fractures of the condyles or the tibia plateau but also due to traumatic or degenerative injuries of the medial and/or lateral meniscus or due to joint instability after traumatic or degenerative damage to the cruciate or collateral ligaments. This type of arthritis is similar to degenerative osteoarthritis and may develop years after a fracture, the ligament injury, meniscual tear or patello-femoral incongruency.