Medial unicondylar knee arthroplasty and high tibial osteotomy: Combined procedure for medial knee osteoarthritis with axis deviation

Background: Unicondylar knee arthroplasty (UKA) is an effective procedure for isolated medial or lateral knee osteoarthritis (OA). Mechanical axis deviation could lead to overloading of implants or unaffected knee compartments; therefore, unicondylar knee OA with severe juxta-articular coronal deformity cannot be addressed by UKA alone. This article presents a surgical technique of combined medial UKA and medially opening wedge high tibial osteotomy (HTO) for medial knee OA with juxta-articular tibal varus deformity. Methods: A preoperative deformity analysis on weight-bearing full leg radiographs is carried out according to Paley. The HTO is performed further distally than usual to ensure a sufficient bony bridge between HTO and tibial UKA components and UKA surgery is performed. The autologous material obtained from UKA bone cuts is used to fill the opening HTO gap. Fixation is achieved with a locking compression 3.5 T plate. Postoperative aftercare is the same as routine UKA except for partial weight-bearing of 15 kg for 6 weeks. Results: The technique of combined medial UKA and HTO for medial knee OA with juxta-articular coronal tibial deformity is an alternative to total knee arthroplasty and has the potential to further expand the indications for UKA. The precise value of this technique needs to be evaluated further in comparative outcome studies. The supplemental video details the aforementioned surgical technique. © 2017, Springer Medizin Verlag GmbH.