What condition may be indicated by crepitus during the hyperextension test?

The presence of crepitus during the hyperextension test is indicative of osteochondritis dissecans. This condition is characterized by the separation of a segment of cartilage from the underlying bone, often due to insufficient blood supply, and involves the joint's articular surface. When the hyperextension test is performed, the joint’s range of motion can lead to the rubbing of the damaged cartilage against bone, creating a grinding or crackling sound known as crepitus. This symptom is particularly relevant in osteochondritis dissecans, as it points to the underlying structural issue within the joint that affects normal movement and stability.

In contrast, while arthritis can also cause crepitus due to joint degeneration, its symptoms are typically broader and involve chronic pain, stiffness, and swelling, rather than being specifically linked to a hyperextension test. A ulnar collateral ligament (UCL) tear and radial collateral ligament (RCL) sprains are more focused on ligament integrity and stability issues, and while they may be associated with joint noises, they do not typically result in crepitus that is specifically tied to the hyperextension motion. Thus, the distinct nature of crepitus associated with osteochondritis dissecans during this specific test makes it the