Closed‐wedge high tibial osteotomy is more advantageous to maintain the correction than open‐wedge high tibial osteotomy in osteopenic patients

Abstract Purpose To compare the incidence of correction loss and survival rate between closed‐wedge and open‐wedge high tibial osteotomies (CWHTO and OWHTO, respectively) in patients with osteopenic and normal bone. Methods Retrospective review was conducted for 115 CWHTOs and 119 OWHTOs performed in osteopenic patients [− 2.5 < Bone mineral density (BMD) T scores ≤ − 1] and 136 CWHTOs and 138 OWHTOs performed in normal patients (BMD T score > − 1) from 2012 to 2019. Demographics were not different between CW‐ and OWHTOs in osteopenic and normal patients (n.s., respectively). Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and posterior tibial slope (PTS) were evaluated pre‐ and postoperatively (2 weeks after HTO). The occurrence of hinge fractures was investigated using radiographs taken on the operation day. The correction change was calculated as the last follow‐up value minus postoperative MPTA. Correction loss was defined when the correction change was ≥ 3°. The survival rate (failure: correction loss) was investigated. Results There were no significant differences in the pre and postoperative MA, MPTA, PTS, and value changes between CW‐ and OWHTOs in osteopenic and normal patients (n.s., respectively); the incidence of unstable hinge fractures also did not differ significantly (CWHTO vs. OWHTO = 7 vs. 7.6% in osteopenic patients; 2.9 vs. 3.6% in normal patients; n.s., respectively). The average correction change (CWHTO = − 0.6°, OWHTO = − 1.3°, p = 0.007), incidence of correction loss (CWHTO = 1.7%, OWHTO = 9.2%, p = 0.019), and 5‐year survival rates (CWHTO = 98.3%, OWHTO = 90.8%, p = 0.013) differed significantly in osteopenic patients; there were no significant differences in these results in normal patients (n.s., respectively). Conclusion CWHTO was more advantageous than OWHTO regarding the correction loss in osteopenic patients. Intra‐ and postoperative care that consider poor bone quality will be required when performing OWHTOs in osteopenic patients. Level of evidence III.