PHOENIX (Picking up Hidden Osteoporosis Effectively during Normal CT Imaging without additional X-rays): protocol for a randomised, multicentre feasibility study.

INTRODUCTION: Two million out of the UK's 5 million routine diagnostic CT scans performed each year incorporate the thoracolumbar spine or pelvic region. Up to one-third reveal undiagnosed osteoporosis or vertebral fractures. We developed an intervention, Picking up Hidden Osteoporosis Effectively during Normal CT Imaging without additional X-rays ('PHOENIX'), to facilitate early detection and management of osteoporosis in people attending hospitals for CT scans. METHODS AND ANALYSIS: A multicentre, randomised, pragmatic feasibility study. From the general CT-attending population, women aged ≥65 years and men aged ≥75 years attending for CT scans are invited to participate, via a novel consent form incorporating Fracture Risk Assessment (FRAX) questions. Those at increased 10-year risk (within the amber or red zones of the UK FRAX graphical outputs for further action) are block randomised (1:1:1) to (1) PHOENIX intervention, (2) active control or (3) usual care. The PHOENIX intervention comprises (i) retrieving the CT scans using the NHS Image Exchange Portal, (ii) Mindways QCT Pro software analysis of CT hip and spine none density with CT vertebral fracture assessment, (iii) sending the participants' general practitioner (GP) a clinical report including diagnosis, necessary investigations and recommended treatment. Baseline CT scans from groups 2 and 3 are assessed with the PHOENIX intervention only at study end. Assuming 25% attrition, the study is powered to find a predicted superior osteoporosis treatment rate with PHOENIX (20%) vs 16% among patients whose GPs were sent the FRAX questionnaire only (active control) and 5% in the usual care group. Five hospitals are participating to determine feasibility. The co-primary feasibility outcome measures are (a) ability to randomise 375 patients within 10 months and (b) retention of 75% of survivors, completing their 1-year bone health outcome questionnaire. Secondary 1-year outcomes include osteoporosis/vertebral fracture identification rates and osteoporosis treatment rates. Stakeholder acceptability and economic aspects are evaluated. ETHICS AND DISSEMINATION: Approved by committee (National Research Ethics Service) East of England (EE) as REF/19/EE/0176. Dissemination will be through the Royal Osteoporosis Society (to patients and public) as well as to clinician peers via national and international bone/rheumatology scientific and clinical meetings. TRIAL REGISTRATION NUMBER: ISRCTN14722819.

Focal osteoporosis defects play a key role in hip fracture.

BACKGROUND: Hip fractures are mainly caused by accidental falls and trips, which magnify forces in well-defined areas of the proximal femur. Unfortunately, the same areas are at risk of rapid bone loss with ageing, since they are relatively stress-shielded during walking and sitting. Focal osteoporosis in those areas may contribute to fracture, and targeted 3D measurements might enhance hip fracture prediction. In the FEMCO case-control clinical study, Cortical Bone Mapping (CBM) was applied to clinical computed tomography (CT) scans to define 3D cortical and trabecular bone defects in patients with acute hip fracture compared to controls. Direct measurements of trabecular bone volume were then made in biopsies of target regions removed at operation. METHODS: The sample consisted of CT scans from 313 female and 40 male volunteers (158 with proximal femoral fracture, 145 age-matched controls and 50 fallers without hip fracture). Detailed Cortical Bone Maps (c.5580 measurement points on the unfractured hip) were created before registering each hip to an average femur shape to facilitate statistical parametric mapping (SPM). Areas where cortical and trabecular bone differed from controls were visualised in 3D for location, magnitude and statistical significance. Measures from the novel regions created by the SPM process were then tested for their ability to classify fracture versus control by comparison with traditional CT measures of areal Bone Mineral Density (aBMD). In women we used the surgical classification of fracture location ('femoral neck' or 'trochanteric') to discover whether focal osteoporosis was specific to fracture type. To explore whether the focal areas were osteoporotic by histological criteria, we used micro CT to measure trabecular bone parameters in targeted biopsies taken from the femoral heads of 14 cases. RESULTS: Hip fracture patients had distinct patterns of focal osteoporosis that determined fracture type, and CBM measures classified fracture type better than aBMD parameters. CBM measures however improved only minimally on aBMD for predicting any hip fracture and depended on the inclusion of trabecular bone measures alongside cortical regions. Focal osteoporosis was confirmed on biopsy as reduced sub-cortical trabecular bone volume. CONCLUSION: Using 3D imaging methods and targeted bone biopsy, we discovered focal osteoporosis affecting trabecular and cortical bone of the proximal femur, among men and women with hip fracture.

Novel assessment of the sternoclavicular joint with computed tomography for planning interventional approach.

OBJECTIVES: To describe the plane of the sternoclavicular joint (SCJ) to aid planning of instrument orientation during invasive procedures. METHODS: Computed tomography (CT) images of 80 consecutive patients aged 25 to 40 years with appropriate chest imaging series were retrospectively reviewed. Patients with a previous median sternotomy, fused manubriosternal joint or fracture were excluded. The medial clavicle was found to vary greatly in its anatomy such that a representative morphology could not be described. The manubrium was found to be a more consistent structure and was examined in more detail. The angulation of the SCJ was measured in three orthogonal planes using CT multiplanar reformats. Each SCJ (160 in total) was assessed for transverse, coronal, and sagittal angulation of the central manubrial articular surface in respect to the long axis of the manubrial body using a newly devised measurement technique. RESULTS: The mean angles (± standard deviation) of the SCJs were 62.4 ± 9.7° to the transverse plane, 149.3 ± 7.3° to the coronal plane and 69.8 ± 7.5 to the sagittal plane. There was no significant difference in transverse (p = 0.41) or sagittal (p = 0.60) angulation between sides, however there was a significant difference for the coronal plane (p = 0.04). No significant differences were noted between the sexes in any plane. CONCLUSIONS: Increasing use of invasive diagnostic and treatment techniques dictate that a safe approach to the joint should be used to reduce the risk of iatrogenic injury. This study adds to existing knowledge of SCJ anatomy and its variation within the population. Understanding this can minimize the risk to adjacent structures when approaching the SCJ with injection needles or arthroscopic instruments.