Osteoporosis exacerbates perioperative complications in total knee arthroplasty: a 10-Year nationwide analysis

​​BACKGROUND: Osteoporosis, a prevalent comorbidity in patients undergoing total knee arthroplasty (TKA), is associated with compromised bone quality and increased susceptibility to postoperative complications. However, its independent impact on perioperative outcomes remains poorly quantified. This study aimed to elucidate the association between preoperative osteoporosis and adverse outcomes following TKA. ​​METHODS: Using the National Inpatient Sample (NIS) database (2010-2019), we identified 1,330,099 TKA patients, of whom 56,888 (4.28%) had preoperative osteoporosis. Propensity score matching (1:1) was performed to balance baseline covariates. Outcomes included perioperative complications, length of stay (LOS), hospital costs, and resource utilization. Multivariable logistic regression models were used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI). ​​RESULTS: Osteoporotic patients exhibited significantly higher risks for major complications compared to non-osteoporotic counterparts: periprosthetic fracture (aOR = 2.13; 95% CI = 1.31-3.45; P < 0.001), prosthetic loosening (aOR = 1.26; 95% CI = 1.11-1.43; P < 0.001), and postoperative hemorrhage (aOR = 1.41; 95% CI = 1.15-1.72; P < 0.001). Additionally, osteoporosis was independently associated with prolonged LOS (aOR = 1.11, 95% CI: 1.07-1.14, P < 0.001) and increased hospitalization costs (aOR = 1.07, 95% CI: 1.04-1.10, P < 0.001). Notably, complications such as lower limb peripheral nerve injuries (aOR = 1.30), muscle atrophy (aOR = 2.77), blood transfusion (aOR = 1.23), stroke (aOR = 1.26), urinary tract infection (aOR = 1.10), and pressure ulcers (aOR = 1.53) were also more frequent in osteoporotic patients. ​​CONCLUSIONS: Preoperative osteoporosis independently increases the risk of major perioperative complications, including periprosthetic fracture (aOR = 2.13), prosthetic loosening (aOR = 1.26), and postoperative bleeding (aOR = 1.41), while increasing hospital resource utilization (prolonged LOS: aOR = 1.11; excess costs: aOR = 1.07). These findings advocate for routine osteoporosis screening, optimization of bone health preoperatively, and enhanced postoperative surveillance to mitigate risks and improve long-term implant durability. Integrating osteoporosis management into TKA care pathways may reduce hospital-associated infections and enhance patient outcomes.