Are the results of total knee arthroplasty after high tibial osteotomy worse?

Background In some cases, total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is necessary. HTO can adversely affect anatomy and alignment resulting in more complicated and challenging TKA surgery. The aim of this study was to investigate whether patients having undergone HTO benefit from TKA to the same extent as patients with primary osteoarthritis of the knee. Methods A total of 44 patients after HTO and 1703 patients with primary osteoarthritis of the knee were identified in the local registry. To reduce confounders, a 1:1 propensity score matched-pair analysis (age, gender, BMI, comorbidities) was carried out in patients with a 5-year follow-up. This resulted in 35 matched pairs, which were compared for knee function, pain level, satisfaction and perioperative data (operative time, implant type, complications) and revisions. Results Patients having undergone HTO had no significant differences in knee function prior and 5 years after surgery but a significantly higher pain level. Despite the higher pain level before and after TKA, there was a similar satisfaction with the result of the surgery. The operative time for TKA was significantly longer after HTO and modular implants with stem and wedges were used significantly more often. The two cohorts did not differ with respect to complications within the first 3 months after surgery. The revision rate within 5 years was not increased in patients after HTO. Conclusion Patients having undergone HTO achieved a similar knee function in comparison to patients with primary osteoarthritis of the knee after TKA. However, a higher pre- and postoperative pain level was recorded in patients following HTO. The surgical effort was significantly higher after HTO.