Intraoperative Bone-Quality Assessments Are Reliable Compared with Opportunistic CT-Based Hounsfield Unit Measurements

Background: Bone density can impact treatment decisions for orthopaedic conditions. While ad-hoc intraoperative surgeon assessment of bone quality is common, the accuracy of such evaluation remains unknown. The primary purpose of this study was to determine whether orthopaedic surgeons’ intraoperative assessment of bone quality closely correlated with validated measures. Methods: In this prospective cross-sectional study, we enrolled adult patients undergoing orthopaedic surgery at a Level-I trauma center. Eligibility required an opportunistic computed tomography (CT) scan of the lumbar spine, glenoid, wrist, pelvis/femur, proximal tibia, or calcaneus. Seven surgeons, blinded to objective measures of bone quality, provided intraoperative bone-quality assessments using a 10-point Likert scale and categorized bone quality as normal, osteopenic, or osteoporotic. Hounsfield units (HUs) were measured on CT using a previously published technique. All images were reviewed by a single orthopaedic surgeon, blinded to intraoperative bone-quality assessments. Results: Of the 229 patients enrolled, 215 had available CT data and were included in the study. The average age of these patients was 44 years (range, 18 to 95 years), with 40.5% being female. Over half of the patients (61%) were Black or African American, while a quarter of the patients (25%) were White. The most common surgical sites included the femur (39 patients, 18.1%), ankle (31, 14.4%), and acetabulum (26, 12.1%). A positive linear relationship between HU and surgeon bone-quality assessments was observed (r = 0.66; p < 0.0001), which was consistent across surgical anatomic sites. Abnormal bone quality was correctly identified by surgeon assessment with 84% sensitivity and 97% specificity. Conclusions: This study demonstrated that surgeons can reliably detect abnormal bone quality through intraoperative assessment across numerous surgical sites. Intraoperative assessments may provide actionable and reliable feedback regarding bone density without additional cost or radiation in cases when opportunistic scans are not available. This information can inform intraoperative decision-making and presents opportunities for bone-health interventions. Level of Evidence: Diagnostic Level II . See Instructions for Authors for a complete description of levels of evidence.