Related Experiment Video
Updated: May 23, 2026

Measurement of Healthy and Injured Triceps Surae Morphology
Published on: October 27, 2023
Age and sex differences in tibia morphology in healthy adult Caucasians
Vanessa D Sherk1, Debra A Bemben, Michael G Bemben
1Department of Health and Exercise Science, University of Oklahoma, Norman, OK, USA. vanessa.sherk@ucdenver.edu
Unlabelled:
Variability in peripheral Quantitative Computed Tomography (pQCT) measurement sites limits direct comparisons of results between studies. Further, it is unclear what estimates of bone strength are most indicative of changes due to aging, disease, or interventions. The purpose of this study was to examine age group and sex differences in tibia morphology. Additional purposes of this study were to determine which tibia site or sites are most sensitive for detecting age and sex differences.
Methods:
Self-identifying Caucasian men (n=55) and women (n=59) ages 20-59 years and separated by decades had their non-dominant tibias measured with pQCT (Stratec XCT 3000) at every 10% of the limb length from 5% to 85% (distal to proximal). Volumetric BMD and BMC of the total, cortical and trabecular bone were determined, as well as periosteal (PeriC) and endosteal (EndoC) circumferences, and cortical thickness (CTh).
Results:
There were significant (p<0.01) site effects for all BMC, vBMD, PeriC and EndoC measures. Large sex differences (men>women) in Tot.BMC (21-28%) were paralleled by differences in Cort.BMC (21-25%) (p<0.01). Site∗sex interaction effects were significant (p<0.05) for BMC (peak sex difference: 5%, 15%, 25%, 85% sites) and circumference (peak sex difference: 65% site) variables. CTh and total vBMD were lowest (p<0.05) in 50-59 year group, and EndoC was highest in the 50-59 year group. Site∗age interactions existed for Cort.vBMD, Tot.BMC (85% site), and EndoC (25%, 35%, 55%-85% sites). Correcting for bone free lean body mass (BFLBM) greatly reduced sex differences, eliminating sex∗site interaction effects, but sex main effects remained significant. Correcting for BFLBM did not eliminate age effects.
Conclusion:
The magnitude of age and sex differences in tibia variables varied by measurement site demonstrating the need for standardization of measurement sites.
Related Concept Videos
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Bones of the Lower Limb: Tibia and Fibula
Introduction to the Skeletal System
Components of the Skeletal System
Bone, or osseous tissue, is a hard connective tissue that forms an internal support structure for the human body. Bones shield vulnerable organs and soft tissue from external forces. For example, the vertebral bones protect and support the spinal cord.
Cartilage, a semi-rigid connective tissue found in regions such as...
Bones of the Lower Limb: Femur and Patella
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Classification of Bones
Long and Short Bones
The appendicular skeleton, particularly the upper and lower limbs, is primarily made of long and short bones. The long...

