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The Hounsfield value for cortical bone geometry in the proximal humerus—an in vitro study

Abstract

Introduction

Fractures of the proximal humerus represent a major osteoporotic burden. Recent developments in CT imaging have emphasized the importance of cortical bone thickness distribution in the prevention and management of fragility fractures. We aimed to experimentally define the CT density of cortical bone in the proximal humerus for building cortical geometry maps.

Methods

With ethical approval, we used ten fresh-frozen human proximal humeri. These were stripped of all soft tissue and high-resolution CT images were then taken. The humeral heads were then subsequently resected to allow access to the metaphyseal area. Using curettes, cancellous bone was removed down to hard cortical bone. Another set of CT images of the reamed specimen was then taken. Using CT imaging software and a CAD interface, we then compared cortical contours at different CT density thresholds to the reference inner cortical contour of our reamed specimens. Working with 3D model representations of these cortical maps, we were able to accurately make distance comparison analyses based on different CT thresholds.

Results

We could compute a single closest value at 700 HU. No difference was found in the HU-based contours generated along the 500–900 HU pixels (p = 1.000). The contours were significantly different from those generated at 300, 400, 1,000, and 1,100 HU.

Conclusions

A Hounsfield range of 500–900 HU can accurately depict cortical bone geometry in the proximal humerus. Thresholding outside this range leads to statistically significant inaccuracies. Our results concur with a similar range reported in the literature for the proximal femur. Knowledge of regional variations in cortical bone thickness has direct implications for basic science studies on osteoporosis and its treatment, but is also important for the orthopedic surgeon since our decision for treatment options is often guided by local bone quality.

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References

  1. Lippuner K, Johansson H, Kanis JA, Rizzoli R. Remaining lifetime and absolute 10-year probabilities of osteoporotic fracture in Swiss men and women. Osteoporos Int. 2009;20(7):1131–40.

    PubMed  Article  CAS  Google Scholar 

  2. Griffith JF, Engelke K, Genant HK. Looking beyond bone mineral density: imaging assessment of bone quality. Ann N Y Acad Sci. 2010;1192(1):45–56.

    PubMed  Article  Google Scholar 

  3. Ito M, Wakao N, Hida T, Matsui Y, Abe Y, Aoyagi K, et al. Analysis of hip geometry by clinical CT for the assessment of hip fracture risk in elderly Japanese women. Bone. 2010;46(2):453–7.

    PubMed  Article  Google Scholar 

  4. Verhulp E, van Rietbergen B, Huiskes R. Load distribution in the healthy and osteoporotic human proximal femur during a fall to the side. Bone. 2008;42(1):30–5.

    PubMed  Article  CAS  Google Scholar 

  5. de Bakker PM, Manske SL, Ebacher V, Oxland TR, Cripton PA, Guy P. During sideways falls proximal femur fractures initiate in the superolateral cortex: evidence from high-speed video of simulated fractures. J Biomech. 2009;42(12):1917–25.

    PubMed  Article  Google Scholar 

  6. Mayhew PM, Thomas CD, Clement JG, Loveridge N, Beck TJ, Bonfield W, et al. Relation between age, femoral neck cortical stability, and hip fracture risk. Lancet. 2005;366(9480):129–35.

    PubMed  Article  Google Scholar 

  7. Carpenter RD, Beaupre GS, Lang TF, Orwoll ES, Carter DR. New QCT analysis approach shows the importance of fall orientation on femoral neck strength. J Bone Miner Res. 2005;20(9):1533–42.

    PubMed  Article  Google Scholar 

  8. Thiele OC, Eckhardt C, Linke B, Schneider E, Lill CA. Factors affecting the stability of screws in human cortical osteoporotic bone: a cadaver study. J Bone Joint Surg Br. 2007;89(5):701–5.

    PubMed  Article  CAS  Google Scholar 

  9. Boileau P, Walch G. The three-dimensional geometry of the proximal humerus. Implications for surgical technique and prosthetic design. J Bone Joint Surg Br. 1997;79(5):857–65.

    PubMed  Article  CAS  Google Scholar 

  10. Robertson DD, Yuan J, Bigliani LU, Flatow EL, Yamaguchi K. Three-dimensional analysis of the proximal part of the humerus: relevance to arthroplasty. J Bone Joint Surg Am. 2000;82-A(11):1594–602.

    PubMed  CAS  Google Scholar 

  11. Neer 2nd CS. Displaced proximal humeral fractures. I. Classification and evaluation. J Bone Joint Surg Am. 1970;52(6):1077–89.

    PubMed  Google Scholar 

  12. Koval KJ, Blair B, Takei R, Kummer FJ, Zuckerman JD. Surgical neck fractures of the proximal humerus: a laboratory evaluation of ten fixation techniques. J Trauma. 1996;40(5):778–83.

    PubMed  Article  CAS  Google Scholar 

  13. Williams Jr GR, Copley LA, Iannotti JP, Lisser SP. The influence of intramedullary fixation on figure-of-eight wiring for surgical neck fractures of the proximal humerus: a biomechanical comparison. J Shoulder Elbow Surg. 1997;6(5):423–8.

    PubMed  Article  Google Scholar 

  14. Tingart MJ, Apreleva M, von Stechow D, Zurakowski D, Warner JJ. The cortical thickness of the proximal humeral diaphysis predicts bone mineral density of the proximal humerus. J Bone Joint Surg Br. 2003;85(4):611–7.

    PubMed  Article  Google Scholar 

  15. Nho SJ, Brophy RH, Barker JU, Cornell CN, MacGillivray JD. Innovations in the management of displaced proximal humerus fractures. J Am Acad Orthop Surg. 2007;15(1):12–26.

    PubMed  Google Scholar 

  16. Hepp P, Lill H, Bail H, Korner J, Niederhagen M, Haas NP, et al. Where should implants be anchored in the humeral head? Clin Orthop Relat Res. 2003;415:139–47.

    PubMed  Article  Google Scholar 

  17. Liew AS, Johnson JA, Patterson SD, King GJ, Chess DG. Effect of screw placement on fixation in the humeral head. J Shoulder Elbow Surg. 2000;9(5):423–6.

    PubMed  Article  Google Scholar 

  18. Tingart MJ, Lehtinen J, Zurakowski D, Warner JJ, Apreleva M. Proximal humeral fractures: regional differences in bone mineral density of the humeral head affect the fixation strength of cancellous screws. J Shoulder Elbow Surg. 2006;15(5):620–4.

    PubMed  Article  Google Scholar 

  19. Yamada M, Briot J, Pedrono A, Sans N, Mansat P, Mansat M, et al. Age- and gender-related distribution of bone tissue of osteoporotic humeral head using computed tomography. J Shoulder Elbow Surg. 2007;16(5):596–602.

    PubMed  Article  Google Scholar 

  20. Park SH, Kim SJ, Park BC, Suh KJ, Lee JY, Park CW, Shin IH, Jeon IH. Threedimensional osseous micro-acrchitecture of the distal humerus: implications for internal fixation of osteoporotic fracture. J Shoulder Elbow Surg. 2010;19(2):244–50.

    Google Scholar 

  21. Hangartner TN, Short DF. Accurate quantification of width and density of bone structures by computed tomography. Med Phys. 2007;34(10):3777–84.

    PubMed  Article  Google Scholar 

  22. Poole KES, Rose CM, Mayhew PM, Brown J, Clement JG, Thomas C, Reeve J, Loveridge N. Thresholds for the measurement of cortical thickness in-vivo using computed tomography (the 100 women study), Calcif. Tissue Int. 2008;83(1):33.

  23. Kang Y, Engelke K, Kalender WA. A new accurate and precise 3-D segmentation method for skeletal structures in volumetric CT data. IEEE Trans Med Imaging. 2003;22(5):586–98.

    PubMed  Article  Google Scholar 

  24. Muraru L, Van Lierde C, Naert I, Vander Sloten J, Jaecques SVN. Three-dimensional finite element models based on in vivo microfocus computed tomography: elimination of metal artefacts in a small laboratory animal model by registration with artefact-free reference images. Adv Eng Softw. 2009;40(11):1207–10.

    Article  Google Scholar 

  25. Wang J, Ye M, Liu Z, Wang C. Precision of cortical bone reconstruction based on 3D CT scans. Comput Med Imaging Graph. 2009;33(3):235–41.

    PubMed  Article  Google Scholar 

  26. Treece GM, Gee AH, Mayhew PM, Poole KE. High-resolution cortical bone thickness measurement from clinical CT data. Med Image Anal. 2010;14(3):276–90.

    PubMed  Article  CAS  Google Scholar 

  27. Garg A, Deland J, Walker PS. Design of intramedullary femoral stems using computer graphics. Eng Med. 1985;14(2):89–93.

    PubMed  Article  CAS  Google Scholar 

  28. Reuben JD, Chang CH, Akin JE, Lionberger DR. A knowledge-based computer-aided design and manufacturing system for total hip replacement. Clin Orthop Relat Res. 1992;285:48–56.

    PubMed  Google Scholar 

  29. Hua J, Mai S, Walker PS. Determination of the Hounsfield unit in CT-scan for designing custom femoral stems. Proc ISSCP Amelia Island, Fl, 1993:11–2.

  30. Adam F, Hammer DS, Pape D, Kohn D. Femoral anatomy, computed tomography and computer-aided design of prosthetic implants. Arch Orthop Trauma Surg. 2002;122(5):262–8.

    PubMed  Article  Google Scholar 

  31. Aamodt A, Kvistad KA, Andersen E, Lund-Larsen J, Eine J, Benum P, et al. Determination of Hounsfield value for CT-based design of custom femoral stems. J Bone Joint Surg Br. 1999;81(1):143–7.

    PubMed  Article  CAS  Google Scholar 

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The authors declare that they have no conflicts of interest.

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Correspondence to Daren Lim Fat.

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Lim Fat, D., Kennedy, J., Galvin, R. et al. The Hounsfield value for cortical bone geometry in the proximal humerus—an in vitro study. Skeletal Radiol 41, 557–568 (2012). https://doi.org/10.1007/s00256-011-1255-7

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  • DOI: https://doi.org/10.1007/s00256-011-1255-7

Keywords

  • Osteoporosis
  • Quantitative CT
  • Cortical bone geometry
  • Proximal humerus fracture
  • Image segmentation