Age and gender as determinants of the bone quality of the greater tuberosity: A HR-pQCT cadaver study
1 Department of Trauma Surgery, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaningerstrasse 22, D-81675, Munich, Germany
2 Department of Surgery-Campus Innenstadt, Ludwig-Maximilians-Universitaet Muenchen, Nussbaumstrasse 20, D-80336, Munich, Germany
3 AO Research Institute, AO Foundation, Clavadelerstrasse 8, CH-7270, Davos, Switzerland
4 Department of Anatomy, Ludwig-Maximilians-Universitaet Muenchen, Pettenkoferstrasse 11, D-80336, Munich, Germany
5 Institute of Clinical Radiology - Campus Innenstadt, Ludwig-Maximilians-Universitaet Muenchen, Nussbaumstrasse 20, D-80336, Munich, Germany
6 Institute of Forensic Medicine - Campus Innenstadt, Ludwig-Maximilians-Universitaet Muenchen, Nussbaumstrasse 7, D-80336, Munich, Germany
7 Department of Orthopedic Surgery and Orthopedic Sports Surgery, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaningerstrasse 22, D-81675, Munich, Germany
BMC Musculoskeletal Disorders 2012, 13:221 doi:10.1186/1471-2474-13-221Published: 13 November 2012
Age-dependent trabecular changes of the humeral head might weaken the fixation of suture anchors used for rotator cuff (RC) repair. This might lead to suture anchor loosening and thus compromise the integrity of the repair. The aim of this study was to analyze whether the trabecular microstructure within the RC footprint is influenced by age, gender or handedness.
Axial HR-pQCT scans (Scanco Medical) of 64 freshly frozen cadaveric human humeral head specimens (age 72.3 ± 17.4 years) were analyzed to determine the bone volume-to-total volume ratio (BV/TV), trabecular thickness (Trab Th), trabecular number (Trab N) and connectivity density (Conn Dens). Within the RC footprint, 2 volumes of interest (VOI), posteromedial (PM) and anterolateral (AL) and one control VOI in the subarticular bone (SC) were set.
The highest BV/TV was found in SC: 0.22 ± 0.06% vs. PM: 0.04 ± 0.05% vs. AL: 0.02 ± 0.04%; p < 0.05. Trab Th accounted for 0.26 ± 0.05 μm in SC, 0.23 ± 0.09 μm in AL and 0.21 ± 0.05 μm in PM. In parallel, Trab N and Conn Dens were found to be the highest in SC. Gender analysis yielded higher values for BV/TV, Trab Th, Trab N and Conn Dens for PM in males compared to females (p < 0.05). There were no significant findings when comparing both sides. We furthermore found a strong inverse correlation between age and BV/TV, which was more pronounced in the female specimens (r = −0.72, p < 0.00001).
The presented microarchitectural data allow for future subtle biomechanical testing comprising knowledge on age- and sex-related changes of the tuberosities of the humeral head. Furthermore, the insights on the trabecular structure of the humeral head of the elderly may lead to the development of new fixation materials in bone with inferior bone quality.