[Combination of ACL-replacement and high tibial osteotomy].

OBJECTIVE: Replacement of the anterior cruciate ligament (ACL) with an autologous tendon together with a high tibial osteotomy (HTO) in one operation. INDICATION: Simultaneous symptomatic ACL insufficiency and symptomatic varus osteoarthritis. CONTRAINDICATIONS: Risk of a higher complication rate for a one-stage procedure, e.g., in loss of motion due to soft tissue contracture, loss of motion due to insufficiency of a existent ACL replacement with tunnel malplacement, tunnel widening of an existent ACL replacement with the risk of tunnel confluence, infection in a former operation. Varus osteoarthritis with a hollow posteromedial tibial plateau (knee abuser). Exclusion criteria include PLC insufficiency, lateral or posterolateral instability, lateral arthritis. SURGICAL TECHNIQUE: Osteotomy: placement of the two K-wires from the medial tibia about 4-5 cm below the medial tibial plateau towards the lateral hinge about 2 cm below the lateral tibial plateau. Mobilization of the long fibers of the medial collateral ligament distal of the osteotomy, mobilization of the pes anserinus tendons. Frontal and axial osteotomy with an oscillating saw. Completion and opening of the osteotomy with chisels. Opening of the osteotomy with a spreader according to the new leg axis of the preoperative planning. Fixation of the osteotomy with an angle stable plate (PPP Arthrex, Tomofix Synthes). In case of a distal osteotomy of the hiberosity fixation with 2 screws. Arthroscopy: positioning of a 2.4 mm K-wire in the center of the remnant femoral ACL insertion, cannulated drilling according to the graft diameter. Positioning of a 2.4 mm K-wire in the center of the remnant tibial ACL insertion, cannulated drilling. In the case of interference of the tibial tunnel with one of the osteotomy screws, removal of the screw and finishing of the tunnel preparation. Measurement of the length and insertion of the respective osteotomy screw. Insertion of the graft and fixation with a button-wire construct at the femur and with a bioabsorbable interference screw and a lag screw at the tibia. POSTOPERATIVE MANAGEMENT: Postoperative management relating to weight bearing rehabilitation follows osteotomy rules, while range of motion rehabilitation follows the ACL protocol.