Methods and implants to treat anterior cruciate ligament (ACL) injuries are disclosed. The methods involve advancing the insertion of the patellar tendon to the proximal tibia by means of a partial osteotomy and a wedge-shaped cage (30). The wedge-shaped cage is specifically designed to facilitate transfer of not only compressive loads, but also of shear loads due to pull by the patellar tendon at its insertion to the tibial tuberosity. The cage decreases the angle between the patellar tendon and the common tangent plane formed by the condyles of the femur and the condyles of the tibia (sometimes called tibial plateau) and consequently modifies the internal joint force, restoring stability to the joint even if the ACL is ruptured. The methods and implants are applicable to both human and canine patients.