A Novel Osteoporosis Screening Protocol to Identify Orthopedic Surgery Patients for Preoperative Bone Health Optimization

Abstract

Introduction: Osteoporosis is highly prevalent in elective orthopedic surgery. While preoperative bone health optimization decreases osteoporosis-related complications, there is an unmet need to establish who may benefit from preoperative dual-energy x-ray absorptiometry (DXA). This study assesses a novel, simple screening protocol to identify orthopedic surgical patients for preoperative DXA.

Materials/methods: This retrospective cohort study included 628 patients undergoing total knee, hip, or shoulder arthroplasty or thoracolumbar spine fusion. Inclusion criteria were ≥40 years undergoing primary elective surgery. Screening criteria defining who should obtain DXA due to high osteoporosis risk included: female ≥65, male ≥70, fracture history when ≥50 years, or FRAX major osteoporotic fracture risk (without bone mineral density [BMD]-adjustments) ≥8.4%. Osteoporosis was defined by World Health Organization criteria [T-score ≤ -2.5], clinical National Osteoporosis Foundation (NOF) criteria [T-score ≤ -2.5, elevated BMD-adjusted FRAX risk, or prior hip/spine fracture], and modified clinical criteria [NOF criteria simplified to include any non-traumatic prior fracture and FRAX without BMD].

Results: The study included 100 TKAs, 100 THAs, 251 TSAs, and 177 spine fusions, average age 65.6 ± 9.8. DXA was available for 209 patients. Screening criteria recommending DXA was met by 362 patients. For those with DXA, screening sensitivity was .96 (CI: .78 to .99) and specificity was .19 (CI: .14 to .25) for identifying T-score osteoporosis. Similar sensitivity of .99 (CI: .91 to .99) and specificity of .61 (CI: .56 to .66) were found for modified clinical osteoporosis. For modified clinical osteoporosis, 192 patients with osteoporosis met criteria (true pos.), 1 patient with osteoporosis did not meet criteria (false neg.), 170 patients without osteoporosis met criteria (false pos.), and 265 patients without osteoporosis did not meet criteria (true neg.).

Discussion/conclusion: A simple screening protocol identifies orthopedic surgical candidates at risk of T-score or clinical osteoporosis for preoperative DXA with high sensitivity.

Keywords: adult reconstructive surgery; bone health optimization; bone health screening; bone mineral density; fragility fractures; metabolic bone disorders; osteoporosis; spine surgery.

Figure 1.

This algorithm outlines the proposed preoperative bone health optimization initiative, including criteria for DXA testing and how to apply results in surgical planning.

Figure 2.

This algorithm illustrates how the 628 subjects were categorized based on screening indication and modified clinical osteoporosis criteria. In addition to age and fracture history, the FRAX risk factors listed were used to calculate 10-year fracture risk for screening determination.

Figure 3.

Screening protocol sensitivity and specificity when evaluating for World Health Organization T-score (n = 209), National Osteoporosis Foundation clinical osteoporosis (n = 628), and modified clinical osteoporosis criteria (n = 628). (*Error lines represent 95% confidence intervals as calculated by Clopper-Pearson criteria.)