Proximal tibiofibular dislocation in closing-wedge high tibial osteotomy increases the risk of medium and long-term total knee replacement. Background: High tibial osteotomy is an effective treatment for medial osteoarthritis in young patients with varus knee. The lateral closing-wedge high tibial osteotomy (CWHTO) may be managed with tibiofibular dislocation (TFJD) or a fibular head osteotomy (FHO). TFJD may lead to lateral knee instability and thereby affect mid- and long-term outcomes. It also brings the osteotomy survival rate down. Objective: To compare the CWHTO survival rate in function of tibiofibular joint management with TFJD or FHO, and to determine whether medium and long-term clinical outcomes are different between the two procedures. Material & Methods: A retrospective cohort study was carried out that included CWHTO performed between January 2005 to December 2018. Those patients were placed in either group 1 (FHO) or Group 2 (TFJD). Full-leg weight-bearing radiographs were studied preoperatively, one year after surgery and at final follow-up to assess the femorotibial angle (FTA). The Rosenberg view was used to assess the Ahlbäck grade. The Knee Society Score (KSS) was used to assess clinical outcomes and a Likert scale for patient satisfaction. The total knee replacement (TKR) was considered the end of the follow-up and the point was to analyze the CWHTO survival rate. A sub-analysis of both cohorts was performed in patients who had not been FTA overcorrected after surgery (postoperative FTA ≤ 180°, continuous loading in varus). Results: A total of 230 knees were analyzed. The follow-up period ranged from 24–180 months. Group 1 (FHO) consisted of 105 knees and group 2 (TFJD) had 125. No preoperative differences were observed in terms of age, gender, the KSS, FTA or the Ahlbäck scale; neither were there any differences relative to postop complications. The final follow-up FTA was 178.7° (SD 4.9) in group 1 and 179.5° (SD 4.2) in group 2 (p = 0.11). The Ahlbäck was 2.21 (SD 0.5) in group 1 and 2.55 (SD 0.5) in group 2 (p = 0.02) at the final follow-up. The final KSS knee values were similar for group 1 (86.5 ± 15.9) and group 2 (84.3 ± 15.8). Although a non-significant trend of decreased HTO survival in the TFJD group was found (p = 0.06) in the sub-analysis of non-overcorrected knees, which consisted of 52 patients from group 1 (FHO) and 58 from group 2 (TFJD), 12.8% of the patients required TKR with a mean of 88.8 months in group 1 compared to 26.8% with a mean of 54.9 months in the case of group 2 (p = 0.005). However, there were no differences in clinical and radiological outcomes. Conclusion: TFJD associated with CWHTO shows an increase in the conversion to TKR at medium and long-term follow-up with lower osteotomy survival than the CWHTO associated with FHO, especially in patients with a postoperative FTA ≤ 180° (non-overcorrected). There were no differences in clinical, radiological or satisfaction results in patients who did not require TKR. Level of evidence III. Retrospective cohort study.
Total knee arthroplasty after opening– versus closing-wedge high tibial osteotomy. A 135-case series with minimum 5-year follow-up
