Why does an ACL (anterior cruciate ligament) tear in the knee often result in subsequent osteoarthritis even after successful surgical repair of the ligament itself?

💡 Explanation

ACL injury alters knee joint biomechanics, which increases stress on the articular cartilage surfaces. This initiates chondrocyte damage and degradation of the cartilage matrix, predisposing the joint to osteoarthritis because articular cartilage lacks intrinsic healing capacity. Therefore, biomechanical alteration is the key driver, rather than inflammation alone, and surgical repair can't fully restore the original joint mechanics.

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