The collateral ligaments of the knee are robust bundles of connective tissue reinforcing the articulation outside of the joint, medially and laterally.

Lesions of first, second and third level of these ligaments (classified in four main stages) may heal with ‘functional’ treatment, with an elastic muffled bandage (Jones bandage) or with a knee articulated orthopedic brace (with appropriate restrictions movement) load charging the knee as much as tolerated for about 25 days.

In severe injuries of collateral ligaments we can surgically reinsert them with a lot of techniques or replace them using artificial or donor ligaments, especially in older patients.

The anterior and posterior cruciate ligament constitute the so-called central ‘pivot’ of the knee, which in involved in antero-posterior and rotational joint stability control: their position within the joints makes it possible to arthroscopically treat them.

The anterior cruciate ligament is currently reconstructed using more frequently the central third of the patellar tendon (technical Kenneth-Jones-Rosenberg) or semitendinosus tendons, reattached to the tibia and the femur by means of metal or absorbable screws or pins; similarly, the posterior cruciate ligament is reconstructed using for example portion of the quadriceps tendon of the patient.

The arthroscopic reconstruction of knee ligaments can be conveniently performed using tendons from donor, with similar results, but with the advantage of faster and less painful postoperative period.

In more complex capsular ligamentous lesions, the above mentioned ligament reconstructions are to be associated with the capsular repair (especially of posterior internal and external corner, the so-called PAPE and PAPI), as necessary protection to the ligament reconstruction otherwise destined to deterioration in time.

After the arthroscopic reconstruction of the anterior or posterior cruciate ligament it is indicated the maintenance of an orthopedic brace for a period of 4 weeks to limit articular movement.

In knee surgery it is always mandatory appropriate antitromboembolic prophylaxis with heparin to reduce vein vascular risk.