[Arthritis of the Medial Knee Joint Compartment]

23 % of all persons older than 65 years suffer from osteoarthritis of the medial compartment of the knee joint, a very common situation in orthopaedic practice 1. As a result of the demographic trend the number of patients is expected to increase in the future. Based on specific joint biomechanics and kinematics the medial knee joint compartment is more frequently affected than the lateral. Only an understanding of the functional anatomy and underlying pathology allows a critical evaluation of different available conservative and operative treatment options. This article gives an overview of diagnostic and therapeutic strategies of osteoarthritis of the medial knee joint. Frequently performed surgeries, e.g. high tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) will be presented in a comparative manner. The actual scientific evidence will be given with the goal of an evidence based therapy that is adopted to stage and pathology of osteoarthritis of the medial compartment of the knee joint.