Precise 3D Localisation of Cortical Defects Associated with Subcapital, Trans-cervical and Trochanteric Hip Fractures in Life
Bone Biomechanics and Quality (Clinical)
Osteoporosis - Pathophysiology
Osteoporosis - Assessment
Oral Poster Session, Presentation Number: MO0301
Session: Oral Poster Presentations: Clinical
Monday, October 7, 2013 11:10 AM - 11:15 AM, Baltimore Convention Center, Hall A
Poster Sessions, Presentation Number: MO0301
Session: Poster Session III & Poster Tours
Monday, October 7, 2013 12:00 PM - 2:00 PM, Baltimore Convention Center, Discovery Hall-Hall C
* , UNITED KINGDOM, , UNITED KINGDOM, Karen Blesic, University of Cambridge, , UNITED KINGDOM, Thomas Turmezei, University of Cambridge, , UNITED STATES, Madhavi Vindlacheruvu, University of Cambridge, Simon Donell, University of East Anglia, Jan Vaculik, Charles University Prague, Pavel Dungl, Charles University Prague, Martin Horak, Homolka Hospital,, , CZECH REPUBLIC, Andrew Gee, University of Cambridge
The precise distribution of cortical bone is likely to determine the location and type of hip fracture sustained during a trip, stumble or fall. Since osteoporosis medications and exercise also enhance cortical bone in key areas (Poole et al 2011), each person may need a tailored hip fracture prevention strategy depending on their existing bone structure. We applied 3D cortical bone mapping to ordinary clinical CT scans in order to identify average focal bone defects in women with the three commonest types of acute hip fracture versus healthy controls without fracture. By extending recruitment to our case-control studies in England and the Czech Republic, we could pinpoint systematic differences and visualise the magnitude of the differences in cortical bone between each fracture type and controls with a colour map displayed on an average femur model.
We analysed Siemens or GE CT scans from 144 older women volunteers with acute fracture and 124 age-matched controls from both the Prague Study of Hip Joint in Trauma and the UK FEMCO study. Fractures were diagnosed using the Muller AO classification of fractures into trochanteric (code AO31-A, n=53), transcervical (AO31-B2, n=37) or sub-capital (AO31-B1,B3, n=54) before creating cortical thickness maps of the unfractured contralateral hip. After non-rigid registration to an average femur shape and statistical parametric mapping (SPM), we were able to pinpoint statistically significant foci of lower cortical mass and thickness associated with each fracture type. The generalised linear SPM model allowed for age, weight and country.
The major finding was a marked difference between women with trochanteric fractures, who had an extensive trochanteric cortical defect (fig. 1a) compared with controls, and those with intracapsular fractures (fig 1b & 1c) who had cortical defects located on the superior femoral neck. Closer examination of the two intracapsular fracture types reveals a subtler difference in that the principal cortical defect in transcervical fractures is mostly confined to the upper neck, whereas the defect in subcapital fractures spreads across the anterior femur.
Alongside recent evidence that osteoporosis treatments and exercise have focal effects on the proximal femoral cortex, these results suggest that hip fracture prevention strategies may need to be tailored to improve the focal cortical deficits which are characteristic of each fracture type.
K. Poole, Patent - GB0917524.1 : Other. G. Treece, Patent- GB0917524.1 : Other.
* Presenting Authors(s):
, UNITED KINGDOM