High tibial osteotomy.

High tibial osteotomy (HTO) is a widely accepted and performed procedure to treat medial knee arthrosis. The aim of this review is to evaluate the different surgical options in medial knee arthrosis, focusing on indications, patient's selection, long-term follow-up and survival analysis of HTO. Comparison and pooling of results are challenging because of different evaluation systems, small cohort number, and different surgical techniques. No differences have been described between opening and closing wedged HTO in terms of outcomes. Excellent early survivorship and good clinical outcomes were reported also with concomitant procedures. Correct indications, preoperative workup/planning, and technique selection are essential in achieving good results. The choice between opening and closing wedge osteotomy, graft selection in opening wedge HTO, comparison between HTO and unicompartmental knee arthroplasty, and the results of revised HTO to total knee replacement are currently under debate and will be discussed in the present review.