Osteoporosis International

, Volume 17, Issue 10, pp 1539–1545

Femoral neck cortical geometry measured with magnetic resonance imaging is associated with proximal femur strength

Authors

  • S. L. Manske
    • Department of OrthopaedicsUniversity of British Columbia
  • T. Liu-Ambrose
    • Department of OrthopaedicsUniversity of British Columbia
    • School of Rehabilitation SciencesUniversity of British Columbia
  • P. M. de Bakker
    • Department of OrthopaedicsUniversity of British Columbia
    • Department of Mechanical EngineeringUniversity of British Columbia
  • D. Liu
    • Department of OrthopaedicsUniversity of British Columbia
  • S. Kontulainen
    • Department of OrthopaedicsUniversity of British Columbia
  • P. Guy
    • Department of OrthopaedicsUniversity of British Columbia
  • T. R. Oxland
    • Department of OrthopaedicsUniversity of British Columbia
    • Department of Mechanical EngineeringUniversity of British Columbia
    • Department of Family PracticeUniversity of British Columbia
    • Department of OrthopaedicsUniversity of British Columbia
Original Article

DOI: 10.1007/s00198-006-0162-6

Cite this article as:
Manske, S.L., Liu-Ambrose, T., de Bakker, P.M. et al. Osteoporos Int (2006) 17: 1539. doi:10.1007/s00198-006-0162-6

Abstract

Introduction

Magnetic resonance imaging (MRI) is a promising medical imaging technique that we used to assess femoral neck cortical geometry.

Objectives

Our primary objective was to assess whether cortical bone in the femoral neck assessed by MRI was associated with failure load in a simulated sideways fall, with and without adjustment for total bone size. Our secondary objective was to assess the reliability of the MRI measurements.

Materials and methods

We imaged 34 human cadaveric proximal femora using MRI and dual-energy X-ray absorptiometry (DXA). MRI measurements of cross-sectional geometry at the femoral neck were the cortical cross-sectional area (CoCSAMRI), second area moment of inertia (x axis; IxMRI), and section modulus (x axis; ZxMRI). DXA images were analyzed with the standard Hologic protocol. From DXA, we report the areal bone mineral density (aBMDDXA) in the femoral neck and trochanteric subregions of interest. The femora were loaded to failure at 100 mm/s in a sideways fall configuration (15° internal rotation, 10° adduction).

Results and observations

Failure load (N) was the primary outcome. We observed that the femoral neck CoCSAMRI and IxMRI were strongly associated with failure load (r2=0.46 and 0.48, respectively). These associations were similar to those between femoral neck aBMD and failure load (r2=0.40), but lower than the associations between trochanteric aBMD and failure load (r2=0.70).

Conclusion

We report that MRI holds considerable promise for measuring cortical bone geometry in the femoral neck and for predicting strength at the proximal femur.

Keywords

Cortical boneCross-sectional geometryDXAFailure loadHip fractureMRI

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2006