Biomechanical aspects of anterior cruciate ligament reconstruction in sport

The knee is a complex joint with shifting contact points, pressures and axes that are affected when a ligament is injured. The ACL is a central ligament of the knee. The main functional role of the ACL is to provide stability against anterior tibial translation (ATT) and internal rotation. A common and frequent injury mechanism is non-contact combined valgus- and internal-rotation trauma. An acute ACL rupture is a common orthopaedic trauma, with an estimated incidence of 78 per 100000 persons and a mean age of 32 years in Sweden and an estimated incidence of up to 84 per 100000 persons in the United States. Biomechanical studies have shown that the anterolateral ligament acts as a passive knee stabilizer during internal knee rotation and in the rupture of the anterior cruciate ligament (ACL) and lateral knee structures anterolateral ligament (ALL) is responsible for the presence of a pivot-shift knee phenomenon. It has been shown that isolated ACL reconstruction in patients with ACL and ALL injury cannot restore normal knee kinematics unlike their combined reconstruction. In addition, recent literature shows evidence in terms of improving knee stability after a combined ACL and ALL reconstruction procedure. Moreover, recent clinical studies have shown that ALL has a protective effect on the preservation of ACL graft as well as on the faster return to sport and overall patient satisfaction.

Asst. Prof. Goran Vrgoč, MD., PhD.

Orthopaedic and trauma surgeon
Department of Orthopaedics and Traumatology, University Hospital "Sveti Duh" 
Department of Sports Medicine and Exercise, Faculty of Kinesiology University of Zagreb
GNK Dinamo Zagreb, Croatian Judo Federation, Croatian Triathlon Federation
Croatian Gymnastics Federation, Croatian national youth football team