[Osteotomies around the knee for ligament insufficiency].

BACKGROUND: The osseous geometry of the lower limb has a significant impact on knee instability after ligament injuries, and osseous malalignment has been shown to be a significant risk factor for the failure of ligament reconstruction procedures. Therefore, osteotomies around the knee have gained importance as a combined or isolated treatment option in the ligament deficient and malaligned knee. In addition to unloading of an arthritic knee compartment, osteotomies are also performed to protect a reconstructed ligament and to stabilize the joint without ligament surgery. PROCEDURE: In addition to the correction of varus or valgus malalignment, correction of sagittal imbalance by modifying the tibial slope is an emerging concept. Even small modifications of the tibial slope (≤5°) have been shown to change the anterior-posterior translation in a clinically significant manner. Especially in the case of chronic posterior or posterolateral instability, a valgus-producing and slope-increasing high tibial osteotomy is usually the first treatment option, and ligament surgery is only performed optionally. Isolated modification of the tibial slope is performed infrequently, however, a slope-decreasing osteotomy should be considered in patients with multiple failed ACL reconstructions and a tibial slope of >12°.