ACL reconstruction is surgery to replace a torn anterior cruciate (KROO-she-ate) ligament (ACL) — one of the major ligaments in your knee. ACL injuries most commonly occur during sports that involve sudden stops and changes in direction — such as basketball, soccer, football, tennis, downhill skiing, volleyball and gymnastics.

In an ACL reconstruction, the torn ligament is removed and replaced with a piece of tendon from another part of your knee or from a deceased donor. This surgery is an outpatient procedure that's performed through small incisions around your knee joint.

An ACL reconstruction is performed by a doctor who specializes in surgical procedures of the bones and joints (orthopedic surgeon).