20/05/2026
When an ACL tears completely, it doesnāt just snap ā it retracts. The two ends pull apart, leaving a gap that cannot be bridged by stitching alone.
But thereās a second reason simple repair fails that most people donāt know: the ACL lives inside the knee joint, bathed in synovial fluid. Unlike muscles or skin, this environment has poor blood supply ā which means the healing signals that normally repair tissue never reach it effectively. This is why ACL repairs historically had very high failure rates before reconstruction became the gold standard.
Today, ACL reconstruction using your own tendon ā typically the hamstring or patellar tendon ā has success rates above 90% when combined with proper rehabilitation. The graft gradually becomes a functioning ligament through a biological process called ligamentisation, which takes anywhere from 9 to 12 months to complete.
This is also why returning to sport too early after ACL surgery is one of the most common reasons for re-injury.
š¬ Had an ACL injury or know someone who has? Drop your questions about the surgery or recovery in the comments below.