Summary: This study examines changes in bone density and strength in the spine over the year after hip fracture to see if there are differences in the changes between men and women. Results show losses in the spine that may increase the risk of subsequent vertebral fractures, particularly for women.
Purpose: Compare changes over the first year post-hip fracture in vertebral bone mineral density (BMD) and compressive strength, measured from quantitative computed tomography (QCT) scans of the spine (T12-L1), between women and men.
Methods: QCT scans were performed on 37 participants (21 men and 16 women) at 2 and 12 months post-hip fracture as part of an ancillary observational study of hip fracture recovery in older community-dwelling men and women. Vertebral BMD and compressive strength were calculated using VirtuOst® (O.N. Diagnostics, Berkeley, CA). Unpaired t-tests were used to compare men and women with respect to baseline demographics, measurements of BMD and bone strength for the whole vertebra and the cortical and trabecular compartments, and any changes in these parameters between months 2 and 12.
Results: At 2 months post-fracture, there were no significant sex differences in any measurements of vertebral strength or BMD. Between months 2 and 12, vertebral strength decreased significantly in women (− 3.8%, p < 0.05) but not in men (− 2.3%, p < 0.20), vertebral trabecular BMD decreased similarly in both sexes (− 5.7% women; − 6.0% men), but cortical BMD did not change for either sex.
Conclusion: Despite the small sample size, these findings suggest that appreciable loss of vertebral trabecular bone can occur for both sexes in the year following hip fracture, which may increase the risk of subsequent vertebral fracture, particularly for women.
|2014||Kopperdahl DL, Aspelund T, Hoffmann PF, Sigurdsson S, Siggeirsdottir K, Harris TB, Gudnason V, Keaveny TM. Assessment of incident spine and hip fractures in women and men using finite element analysis of CT scans. J Bone Miner Res. March 2014;29(3):570-580.|
|1985||Cann CE, Genant HK, Kolb FO, Ettinger B. Quantitative computed tomography for prediction of vertebral fracture risk. Bone. 1985;6(1):1-7.|
|2002||Kopperdahl DL, Morgan EF, Keaveny TM. Quantitative computed tomography estimates of the mechanical properties of human vertebral trabecular bone. J Orthop Res. July 2002;20(4):801-805.|
|2003||Crawford RP, Cann CE, Keaveny TM. Finite element models predict in vitro vertebral body compressive strength better than quantitative computed tomography. Bone. 2003;33(4):744-750.|
|2010||Keaveny TM. Biomechanical computed tomography: noninvasive bone strength analysis using clinical computed tomography scans. Annals NY Acad Sci. 2010;1192(1):57-65.|
|2014||Solomon DH, Johnston SS, Boytsov NN, McMorrow D, Lane JM, Krohn KD. Osteoporosis medication use after hip fracture in U.S. patients between 2002 and 2011. J Bone Miner Res. 2014;29(9):1929-1937.|
|2007||Bevill G, Easley SK, Keaveny TM. Side-artifact errors in yield strength and elastic modulus for human trabecular bone and their dependence on bone volume fraction and anatomic site. J Biomech. 2007;40(15):3381-3388.|