CT-based evaluation of volumetric bone density in fragility fractures of the pelvis—a matched case-control analysis

摘要

Abstract Summary This matched case-control study compared the computed tomography (CT)-based regional bone density of patients with fragility fractures of the sacrum to a control without fracture. Patients with a sacral fracture demonstrated a significantly lower regional bone density of the sacrum, the sacral bone density not being correlated with the BMD by DXA of the spine. Introduction The aim of this study is to compare the computed tomography-based regional bone density measured by Hounsfield units (HUs) in patients with and without fragility fractures of the sacrum. Methods Patients aged ≥?50?years with a fragility fracture of the sacrum were compared to patients of similar age and gender who had a fall from standing height without fracture ( n ?=?46). A matched case-control analysis was conducted by retrospective chart review and assessment of areal bone mineral density by lumbar DXA and by volumetric regional HU measurements in uncalibrated CT scans of the sacrum. Results Patients with a sacral fracture (age 74?±?11?years) showed a lower bone density in the body of S1 (HU 85?±?22) when compared to the matched control group without fracture (age 73?±?10?years, HU 125?±?37, p ? r ?=?0.223, p ?=?0.136), and lumbar spine T-scores did not differ between the groups (??2.0?±?1.3 vs. ??1.9?±?1.2, p ?=?0.786). All measurements are based on uncalibrated scans, and absolute HU values are restricted to scans made on Siemens SOMATOM Force or SOMATOM Edge scanners. Conclusions Patients with fragility fractures of the sacrum demonstrated a lower regional volumetric bone density of the sacrum when compared to a cohort without a fracture. Local sacral volumetric bone density as measured by CT seems to be independent from the areal BMD as measured by DXA of the lumbar spine. Level of evidence: level III.