Authors: (including presenting author): :
YT Lee (1), Cina SL Tong(1), James F Griffith(1)
Affiliation: :
Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong
Keyword 1: :
Occult hip fracture
Keyword 5: :
Aging population
Introduction: :
Hong Kong’s demographic shift towards an ageing population will most likely be accompanied by a substantial increase in the burden of fragility fractures of the proximal femur, with reported annual case numbers rising from approximately 6,800 in 2019 to over 7,500 in 2023, and projections suggesting a further marked increase by 2050(1). About 5% of proximal femoral fragility are radiographically occult i.e. not visible on radiographs. Radiographically occult femoral fractures are usually identified on MRI examination. Escalating demand prevents early MRI examination leading to delayed diagnosis and increased hospital costs . Dual-energy computed tomography (DECT) represents a potentially accurate and cost-effective alternative for rapid detection of clinically suspected fragility fractures
Objectives: :
To evaluate the accuracy of DECT in detecting proximal femoral, pubic rami, and sacral fractures in patients with clinically suspected occult hip fracture, compared to MRI as the reference standard.
Methodology: :
Retrospective study of 86 patients scheduled for MRI in Prince of Wales Hospital, from June to Dec 2025 with clinically suspected radiographically occult hip fracture. Pelvic DECT was performed immediately after MRI. DECT images were independently analyzed for bone marrow edema and fracture, using virtual non-calcium (VNCa) reconstructions. Using MRI as the reference standard, the sensitivity, specificity, and accuracy of DECT for fracture detection was calculated.
Result & Outcome: :
25 patients were excluded due to predominant hematopoietic marrow which limits conclusive DECT assessment, leaving 61 patients in the final analysis. MRI identified fractures in 32(53%) of these 61 patients: 21 proximal femur (8 femoral neck, 13 intertrochanteric), 23 pubic rami/sacral, and 1 other fracture. Compared to MRI, standard CT had an overall sensitivity of 69%, a specificity of 100%; and an accuracy of 97% for femoral neck fractures, 83% for intertrochanteric fractures, 91% for rami fractures, 94% for sacral fractures. DECT combined with CT, had an overall sensitivity 98% and specificity of 80% with an accuracy 100% for femoral neck and intertrochanteric fractures, 87% for rami, and 97% for sacral fractures. DECT improved detection particularly for proximal femoral fracture, which warrant timely operative management.
