Vol.:(0123456789) 1 3 Knee Surgery, Sports Traumatology, Arthroscopy https://doi.org/10.1007/s00167-020-05890-0 KNEE Closing‑wedge high tibial osteotomy, a reliable procedure for osteoarthritic varus knee M. Berruto 1  · A. Maione 1  · D. Tradati 1  · P. Ferrua 1  · F. M. Uboldi 1  · E. Usellini 1 Received: 6 February 2019 / Accepted: 29 January 2020 © European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA) 2020 Abstract Purpose The purpose of this study was to analyze the long-term clinical and radiological outcomes of patients who under- went closing-wedge High Tibial Osteotomy (HTO) for the treatment of medial compartment osteoarthritis and to evaluate the conversion rate to knee arthroplasty. Methods A retrospective, non-randomized, monocentric study was performed in our Institution considering 166 patients between 1989 and 2012. The fnal population was composed by 82 patients (94 knees), median age at time of operation was 53 (range 45–73) years. All patients were evaluated clinically (HSS Score, Tegner Scale, VAS and Crosby–Insall Grading) and radiographically (osteoarthritis staging, hip–knee–ankle (HKA) angle, tibial slope and metaphyseal varus). Results Mean follow-up was 11.9 ± 7.2 years. HSS Score increased signifcantly from 70.8 ± 10 to 93.2 ± 9.1 (p < 0.05) instead Tegner Scale increased from 1.3 ± 0 (range 1–4) to 2.8 ± 0.7 (range 2–6) at the last control (n.s.); VAS score signif- cantly decreased from 7.9 ± 1.4 to 1.6 ± 1.1 (p < 0.05) at last follow-up. According to the Crosby–Insall Grading System, 80 patients (97.4%) reported excellent–good results. HKA angle decreased from 6.9° ± 3.5 to 2.6° ± 2.6 (p < 0.01), tibial slope decreased from 10.1° ± 1.4 to 6.8° ± 2.1 (p < 0.05) and fnally the metaphyseal varus decreased from 4.2° ± 0 to 2.1° ± 1.2 (n.s.) at the last follow-up. Adverse events were reported in 4.8%. Osteotomy survivorship rate resulted 92% at 10 years, 82% at 15 years and 80% at 20 years. Sixteen revisions (9.6%) were reported at a mean period of 12.8 years. Conclusions CW-HTO is a valid option for medial osteoarthritis treatment, with successful results in both clinical and radiological outcomes. Level of evidence IV. Keywords Knee osteoarthritis · Closing-wedge HTO · Long-term follow-up · Clinical and radiological outcomes · TKA · Varus Introduction Varus knee alignment, due to loads acting mostly on the medial compartment of the joint during normal gait, is the most frequent axial deviation of the lower limb [15], and it can lead to progressive joint degeneration with medial joint space narrowing and pain during daily activities. There are many surgical options for treating osteoarthri- tis (OA) of the varus knee [22], ranging from arthroscopic procedures on cartilage or meniscus to closing-wedge (CW) or opening-wedge (OW) high tibial osteotomy (HTO) pro- cedures [5, 21, 24], unicompartmental knee arthroplasty (UKA) [6, 26] and total knee arthroplasty (TKA) [27]. In this scenario, HTO is a valid surgical option for symp- tomatic medial OA in middle-aged patients [3, 22]. Over the past decade, OW-HTO has grown in popularity, and is now performed more than CW-HTO. In the December 2017 issue of this journal, which was devoted to HTO, 17 papers dealt with the OW and only six with the CW technique, confrm- ing the increasing focus on OW-HTO [18]. Even though OW-HTO is now the procedure of choice for most surgeons, the results available in the literature show that CW-HTO gives similar [17, 31, 34], and in some cases even better [28], results. To date, few studies in this setting have reported results at a longer than 10-year mean follow-up. * D. Tradati itadart@hotmail.com 1 1° Clinica Ortopedica ASST G. Pini-CTO - UOS Chirurgia Articolare del Ginocchio, Piazza A. Cardinal Ferrari 1, Milan 20122, Italy