Age related changes in the bone microstructure in patients with femoral neck fractures

J M Sanchez-Siles; I Tamimi-Mariño; A R G Cortes; J L Ackerman; D González-Quevedo; E Guerado; A García; F Yaghoubi; M N Abdallah; H Eimar; M Laurenti; A Al-Subaie; F Tamimi

doi:10.1016/j.injury.2020.02.014

Age related changes in the bone microstructure in patients with femoral neck fractures

Injury. 2020 Apr:51 Suppl 1:S12-S18. doi: 10.1016/j.injury.2020.02.014. Epub 2020 Feb 16.

Authors

J M Sanchez-Siles¹, I Tamimi-Mariño², A R G Cortes³, J L Ackerman⁴, D González-Quevedo², E Guerado⁵, A García², F Yaghoubi⁶, M N Abdallah⁷, H Eimar⁸, M Laurenti⁹, A Al-Subaie¹⁰, F Tamimi¹¹

Affiliations

¹ Faculty of Medicine, Department of Surgery, University of Málaga, Bulevar Louis Pasteur, 32, 29010 Málaga, Spain; Hospital Regional Universitario de Malaga, Avenida Carlos Haya SN, Malaga, 29010, Spain. Electronic address: juanm.sanchez.siles.sspa@juntadeandalucia.es.
² Hospital Regional Universitario de Malaga, Avenida Carlos Haya SN, Malaga, 29010, Spain.
³ Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA. Department of Radiology, Harvard Medical School, Boston, MA, USA; Faculty of Dental Surgery, Department of Dental Surgery, University of Malta (Msida, MALTA).
⁴ Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA. Department of Radiology, Harvard Medical School, Boston, MA, USA. Electronic address: jerry@nmr.mgh.harvard.edu.
⁵ Faculty of Medicine, Department of Surgery, University of Málaga, Bulevar Louis Pasteur, 32, 29010 Málaga, Spain. Electronic address: eguerado@uma.es.
⁶ Faculty of Dentistry, McGill University, 3640 University Street, Montreal, Canada, H3A 2B2.
⁷ Faculty of Dentistry, McGill University, 3640 University Street, Montreal, Canada, H3A 2B2. Electronic address: mohamed.abdallah@mail.mcgill.ca.
⁸ Faculty of Medicine and Dentistry, University of Alberta, 2J2.00 WC Mackenzie Health Sciences Centre 8440 112 St. NW Edmonton, Alberta, Canada T6G 2R7. Electronic address: eimar@ualberta.ca.
⁹ Facultad de Farmacia Departamento de Química en Ciencias Farmacéuticas, Universidad Complutense de Madrid, Spain.
¹⁰ Faculty of Dentistry, McGill University, 3640 University Street, Montreal, Canada, H3A 2B2. Electronic address: ahmed.alsubaie@mail.mcgill.ca.
¹¹ Faculty of Dentistry, McGill University, 3640 University Street, Montreal, Canada, H3A 2B2. Electronic address: faleh.tamimimarino@mcgill.ca.

PMID: 32115206
DOI: 10.1016/j.injury.2020.02.014

Abstract

Background: The risk of femoral neck fracture progressively increases with age. However, the reasons behind this consistent increase in the fracture risk can't be completely justified by the decrease in the bone mineral density. The objective of this study was to analyze the correlation between various bone structural features and age.

Study design & methods: A total of 29 consecutive patients who suffered an intracapsular hip fracture and underwent joint replacement surgery between May 2012 and March 2013 were included in this study. A 2 cm × 1 cm Ø cylindrical trabecular bone sample was collected from the femoral heads and preserved in formaldehyde. Bone mineral density (BMD), microarchitecture, organic content and crystallography were analyzed using a Dual-energy X-ray absorptiometry scan, micro-CT scan, and high resolution magic-angle-spinning-nuclear magnetic resonance (MAS-NMR), respectively. Statistical correlations were made using Spearman´s or Pearson´s correlation tests depending on the distribution of the continuous variables.

Results: The mean patient age was 79.83 ± 9.31 years. A moderate negative correlation was observed between age and the hydrogen content in bone (¹H), which is an indirect estimate to quantify the organic matrix (r = -0.512, p = 0.005). No correlations were observed between BMD, trabecular number, trabecular thickness, phosphorous content, apatite crystal size, and age (r = 0.06, p = 0.755; r = -0.008, p = 0.967; r = -0.046, p = 0.812; r = -0.152, p = 0.430, respectively). A weak positive correlation was observed between Charlson´s comorbidity index (CCI) and c-axis of the hydroxiapatite (HA) crystals (r = -0.400, p = 0.035).

Conclusion: The femoral head relative protein content progressively decreases with age. BMD was not correlated with other structural bone parameters and age. Patients with higher comorbidity scores had larger HA crystals. The present results suggest that the progressive increase in the hip fracture risk in elderly patients could be partially explained by the lower bone protein content in this age group.

Keywords: Bone aging; Collagen; Femoral head bone fractures; Hydroxyapatite crystal; Micro-computed tomography; Osteoporosis.

MeSH terms

Absorptiometry, Photon
Aged
Aged, 80 and over
Aging / physiology*
Bone Density / physiology*
Cross-Sectional Studies
Female
Femoral Neck Fractures / diagnostic imaging*
Femoral Neck Fractures / physiopathology
Femur Head / pathology*
Humans
Male
Osteoporotic Fractures / diagnostic imaging*
Osteoporotic Fractures / physiopathology
X-Ray Microtomography