Distal tibial tubercle-high tibial osteotomy with assistance of modifiable spreader in the treatment of varus knee osteoarthritis: A retrospective observational study

As one of the knee preservation surgical approaches, good clinical outcomes of high tibial osteotomy were reported. Aims of this study were to analyze the clinical outcome and pre- and postoperative radiographical parameter and knee functional score between distal tibial tubercle high tibial osteotomy (DTTHTO) and open wedge- high tibial osteotomy (OWHTO) in patients with varus knee osteoarthritis after more than 1 year following-up. A total of 194 consecutive patients in our joint center from March 2016 to October 2021 were enrolled, according to the surgical method, patients were divided into DDTHTO and OWHTO groups. Radiographic parameters of Kellgren-Lawrence grading, hip-knee-ankle angle, weight bearing line ratio and medial tibial plateau angle, knee functional score of American knee society (AKS) score, western Ontario and McMaster universities arthritis index (WOMAC) score, visual analogue score (VAS) were introduced to evaluate clinical outcome for patients who received DDTHTO and OWHTO. There were 103 knees and 89 knees in the OWHTO and DTTHTO group, respectively. Mean weight bearing line ratio for OWHTO and DTTHTO were 25.1 ± 11.7 and 25.2 ± 12.0% respectively, medial tibial plateau angle and hip-knee-ankle angle angle demonstrated that all patients in the present study inherited a varus angle ranges from 3.4° to 9.5°. Preoperative AKS, WOMAC and VAS were 68.4 ± 5.7 versus 69.0 ± 5.9, 109.3 ± 15.0 versus 107.7 ± 14.0 and 6.8 ± 1.0 versus 6.9 ± 0.8, and there was no significant difference between 2 groups (P > .05). Mean postoperative AKS and WOMAC score for patients in both OWHTO and DTTHTO group were significantly improved, moreover, postoperative VAS of DTTHTO patients was lower than that in OWHTO group (P < .05). When comparing the operation time, intraoperative blood loss and bone union time, DHHTO group shows a superiority in these variables over patients in OWHTO (121 ± 29.6 vs 145.7 ± 35.2 minutes, 115.0 ± 20.8 vs 103.3 ± 17.3 mL, 13.7 ± 4.1 vs 12.0 ± 2.8 weeks; P < .005) and incidence of complication was lower for DTTHTO group. DTTHTO in patients with varus knee osteoarthritis has good clinical outcomes, and it can achieve a better postoperative alignment. Operation time and surgical trauma were also less in patients who underwent DTTHTO.