March 8, 2026
Author: Dr. Alexandru Grecu — Senior Orthopedic and Trauma Surgeon
Medically reviewed by Dr. Alexandru Florian Grecu, Senior Orthopedic Surgeon · Published: March 8, 2026 · Updated: 2 mai 2026
The anterior cruciate ligament (ACL) is one of the most important stabilizing structures of the knee. It connects the femur to the tibia and prevents the tibia from sliding forward relative to the femur. It is essential for knee stability in activities involving rotation, changes of direction, and deceleration.
The classic mechanism: a sudden change of direction or landing from a jump with the knee in slight flexion and rotation. In soccer, the typical moment is pivoting on a planted foot. The patient usually feels an audible 'pop', quickly followed by significant swelling and the inability to continue the sporting activity.
An ACL tear is frequently associated with other injuries: a meniscus tear, cartilage damage, or medial collateral ligament injuries.
Clinical examination—specific tests (Lachman, pivot-shift, anterior drawer) have high sensitivity. The Lachman test is considered the most reliable.
MRI—confirms the tear and identifies associated injuries. It is the standard investigation before any therapeutic decision.
Not all ACL tears require surgery. The decision depends on age and activity level, the degree of instability, and associated injuries. A young athlete who wants to return to competitive sports needs reconstruction. A patient with moderate activity levels may function well without an ACL with intensive physical therapy.
ACL reconstruction does not mean 'repairing' the torn ligament—it cannot be sutured. It is replaced with a tendon graft taken from your own body: a graft from the hamstring tendons (most commonly used), a patellar tendon graft, or a quadriceps tendon graft.
The intervention is performed arthroscopically (minimally invasive), with video guidance.
Weeks 1-2: Walking with crutches, reducing swelling, passive mobility exercises.
Weeks 2-6: Progressive increase in mobility, discontinuing crutches, strengthening exercises.
Months 2-4: Normal walking, cycling, swimming. Proprioception and stability exercises.
Months 4-6: Progressive linear running. Advanced muscle strengthening.
Months 6-9: Sport-specific drills, training with changes of direction. Return to competitive sports only after objective functional testing.
Important: a premature return to sport is the main risk factor for re-tearing the ligament.
Partially, yes. Prevention programs (e.g., FIFA 11+) that include stability, proprioception, and correct landing technique exercises have been shown to reduce the risk by 50-70%.