Comparison of radiological features of high tibial osteotomy and tibial condylar valgus osteotomy

Higuchi et al. BMC Musculoskeletal Disorders https://doi.org/10.1186/s12891-019-2764-0 (2019) 20:409 RESEARCH ARTICLE Open Access Comparison of radiological features of high tibial osteotomy and tibial condylar valgus osteotomy Takashi Higuchi1, Hironobu Koseki1,2* , Akihiko Yonekura3, Ko Chiba3, Yusuke Nakazoe4, Shinya Sunagawa1, Chieko Noguchi3 and Makoto Osaki3 Abstract Background: The purpose of this study was to compare radiological features between high tibial osteotomy (HTO) and tibial condylar valgus osteotomy (TCVO), in order to define the radiological indication criteria for TCVO. Methods: Thirty-two cases involving 35 knees that had undergone HTO and the same number that had undergone TCVO for knee osteoarthritis were retrospectively evaluated. Characteristics of both groups did not differ significantly. Lower limb alignment, bone morphology, joint congruity, and joint instability were measured in standing full-length leg and knee radiographs obtained before and after surgery. Results: Radiological features in the TCVO group included greater frequencies of advanced knee OA grade, varus lower limb malalignment, depression of the medial tibial plateau, and varus-valgus joint instability compared to the HTO group before surgery. However, tibial morphology, alignment of the lower limb, and joint instability improved to comparable levels after surgery in both groups. Conclusions: TCVO appears preferable in cases with advanced knee OA, destroyed or inclined medial tibial plateau, widened and subluxated lateral joint, and high varus-valgus joint instability. Keywords: Knee osteoarthritis, High tibial osteotomy, Tibial condylar valgus osteotomy Background Knee osteoarthritis (OA) is one of the most common musculoskeletal disorders, especially among the elderly [1–3]. About 8 million and 25 million individuals are affected by symptomatic and asymptomatic knee OA, respectively, in Japan [4]. Surgical approaches to the treatment of advanced medial unicompartmental knee OA have received considerable attention, and recent studies have highlighted the efficacy of osteotomy and prosthetic arthroplasty [5–7]. Due to advances in both materials and designs, the longevity of total knee arthroplasty (TKA) has increased, and patients from a diverse age range are now undergoing this procedure [6, 7]. However, TKA has some problems with material * Correspondence: 1 Department of Health Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8520, Japan 2 Institute of Biomedical Sciences, Nagasaki University, Nagasaki, Japan Full list of author information is available at the end of the article durability, the risk of metal allergies and patient dissatisfaction with joint range of motion (ROM), especially in young, physically active patients [8–10]. Moreover, concerns have been raised regarding complications such as deep or superficial implant-associated infections, wear of the prosthesis, and vein thromboembolism [11–13]. Therefore, osteotomy procedures have been recommended for young and physically active patients wanting to maintain wide ROM, or for individuals who participate in high-demand activities and want to avoid prosthetic arthroplasty [14, 15]. Open-wedge high tibial osteotomy (HTO), the most common osteotomy procedure for treating knee OA [15, 16], is based on the concept of realignment to redistribute weight-bearing and mechanical stress laterally to areas with less destruction, thus relieving pain and improving function [16]. As tibiofibular joint disruption and peroneal nerve injury are potential complications associated with lateral closed-wedge HTO, the medialapproach open-wedge HTO, which avoids such © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Higuchi et al. BMC Musculoskeletal Disorders (2019) 20:409 complications, has gained popularity [17–19]. Recent developments in internal fixator devices, surgical techniques, and artificial bone graft have enabled early bone union and gap filling, contributing to better clinical outcomes [20]. Even in open-wedge HTO, however, risks include lateral hinge fracture, damage of neurovascular tissue by long proximal screws, loss of correction, and overcorrection due to implant loosening and nonunion [5, 19, 21]. Furthermore, negative effects on the patellofemoral (PF) joint, limited knee extension, and disease progression due to ligamentous joint laxity remain a concern [22–24]. Knee OA with a Kellgren-Lawrence (K/L) grade [25] ≥ 2 or laxity of the knee joint represent risk factors for declining clinical outcomes after HTO [24, 26]. Hence, in terms of indications, HTO is restricted to patients with mild to moderate medial knee OA in which high joint stability is maintained [5, 15]. Tibial condylar valgus osteotomy (TCVO), a novel Lshaped osteotomy developed in the 1990s in Japan, also corrects lower extremity alignment from varus to valgus and shifts the weight-bearing (mechanical) axis laterally [27]. TCVO together with remodeling of the shape of the tibial plateau can improve femorotibial joint congruity and stability. The combined features of osteotomy and arthroplasty are thus promising for effective treatment of severe knee OA [28]. Due to improvements in implants in recent years, TCVO is now making use of locking plates, resulting in shorter postoperative rehabilitation. In our institute, HTO and TCVO are selected individually on a case-by-case basis for medial knee OA and have yielded almost all successful results [27]. However, TCVO is not widespread because of the technical difficulties and uncertain universal radiological indications. To date, no studies have investigated radiological features of TCVO compared to HTO, and radiological indication criteria for TCVO have not been identified. The purpose of this study was to evaluate differences in radiological features between HTO and TCVO in detail, and to clarify the radiological indications for TCVO, to facilitate decision-making when choosing between the two surgical techniques. Page 2 of 10 osteotomy surgery. In particular, OA knees with high varus-valgus joint instability, depression or inclination of the medial tibial plateau (Pagoda deformity [29]), lateral joint dilation, and lateral tibial thrust > 1 cm were included for TCVO, whereas other cases with high joint stability and without depression of the medial tibial plateau were included for HTO, in ac (...truncated)