Prosthetic replacement of the anterior cruciate ligament: a challenge.

Replacing the chronic deficient anterior cruciate ligament (ACL) has been demonstrated to be a challenging surgical procedure. ACL anatomy and structure as well as its biomechanics have been extensively studied in order to understand its properties and improve its reconstruction. Currently the ACL may be replaced by different means. Autogenous grafts, allografts (augmented or not) and prosthetic devices are available. Each method exhibits inherent advantages and drawbacks which are critically reviewed. If one considers the method of choice as the use of the middle third of the patellar tendon, there is no good evidence that prosthetic augmentation of autogenous grafts offers any advantage over autogenous grafts by themselves. The currently available prosthetic ligaments break and generate debris which are responsible for synovitis. Further development of new devices more closely duplicating the biomechanical features of ACL is necessary.