A 65-year-old man experienced a hard fall 40 years ago, when he was a paratrooper: he landed on his right leg and sustained trauma to the right hip. This current radiograph demonstrates a striking example of advanced hypertrophic degenerative osteoarthritic changes of the right hip.
This condition is post-traumatic osteoarthritis (disruptive articular trauma), an uncommon form of secondary osteoarthritis. The typical findings, illustrated here, include marked narrowing of the joint space, large osteophytes extending from the femoral head and the acetabulum (particularly from the superior aspect), and slight compression of the femoral head. In contrast, the radiologic appearance of the left hip is unremarkable for the patient's chronologic age.
Unfortunately, most cases of post-traumatic osteoarthritis are not so clear-cut. To establish the diagnosis, the following findings are necessary:
• The history relates a specific, definable trauma, such as an automobile accident, beating, or crush injury.
• An effusion or structural damage occurred following the injury.
• Similar disease is not present in nontraumatized joints.
Additional points that favor the diagnosis of post-traumatic osteoarthritis include monarticular or pauciarticular involvement; significant arthritis in a joint that is not usually affected (eg, ankle, wrist, elbow, or metacarpophalangeal joint); and radiographic evidence of healed fractures or foreign bodies near the joint in question.
General exposure to heat or cold, hard work, or malnutrition may contribute to degenerative arthritis. However, these factors are not likely to produce post-traumatic osteoarthritic changes. This diagnosis refers to a localized process.