Abstract:Objective To assess the effects of zoledronic acid and denosumab on bone mineral density and function of the lateral hip joint after hip replacement.Methods A total of 100 patients who underwent hip replacement in Tianjin Hospital from January 2020 to December 2022 were selected. Patients were divided into a control group and an experimental group via stratified random sampling, with 50 cases in each group. The control group received zoledronic acid postoperatively, and the experimental group received denosumab postoperatively. The two groups were compared in terms of bone metabolism indicators [C-terminal telopeptide of type I collagen (β-CTX), bone Gla protein (BGP), procollagen type I C-terminal propeptide (PICP), and bone-specific alkaline phosphatase (BALP)], bone formation and resorption markers [insulin-like growth factor-1 (IGF-1), sex hormone-binding globulin (SHBG), and deoxypyridinoline (DPD) ], bone mineral density of the lateral hip joint, the rate of prosthesis loosening, hip joint function (Harris Hip Score), and displacement distance of the prosthesis.Results The differences in levels of β-CTX, BGP, PICP, BALP, IGF-1, SHBG, and DPD before and after surgery were higher in the experimental group than those in the control group (P < 0.05). Comparisons of the bone mineral density of the lateral hip joint, medial migration of the acetabular cup, superior migration of the acetabular cup, and femoral stem subsidence at 1 month, 3 months, 6 months, and 12 months after surgery in the experimental group and the control group showed that they were all different among the time points (P < 0.05). The bone mineral density of the lateral hip joint, medial migration of the acetabular cup, and superior migration of the acetabular cup were different between the experimental group and the control group (P < 0.05), where the bone mineral density of the lateral hip joint was higher and the distances of medial and superior migration of the acetabular cup were shorter in the experimental group than in the control group. There was no difference in the femoral stem subsidence between the two groups (P >0.05). The change trends of the bone mineral density of the lateral hip joint, medial migration of the acetabular cup, and superior migration of the acetabular cup were different between the two groups (P < 0.05). There was no significant difference in the change trend of the femoral stem subsidence between the two groups (P > 0.05). No significant difference was found in the rate of prosthesis loosening at 3 months, 6 months, and 12 months after surgery between the experimental group and the control groups (P > 0.05). The differences of pain severity, function, absence of deformity, and range of motion subitem scores as well as total scores before and after surgery were higher in the experimental group than in the control group (P < 0.05).Conclusions Denosumab is more effective than zoledronic acid in improving bone mineral density and function of the lateral hip joint after hip replacement, highlighting the potential advantages of denosumab in postoperative management.