loading the skeleton — 779,000 triangles from a real scan · 0%

ACT 01 · SKELETON — 206 bones, from a real scan

An adult skeleton has 206 bones. A newborn has around 270 to 300 pieces of bone and cartilage; many of them fuse as you grow — the five sacral vertebrae into one sacrum, the three parts of each hip bone into one. This skeleton is a real scan of one adult man (BodyParts3D), every triangle of it, not a model someone sculpted. The bone lit in gold is the femur, the longest and strongest bone in the body: about a quarter of your height, and at every step it carries more than twice your weight through the head of the hip.

  • SCAN BodyParts3D 4.0 (DBCLS): one adult male, every bone in its measured position. 779,000 triangles, drawn as they are — nothing decimated for this page.
  • FACT 206 bones in a typical adult (Gray's Anatomy). Counts vary a little between people: extra sesamoid bones, an extra rib or a fused vertebra are common.
sources
  • BodyParts3D 4.0, © The Database Center for Life Science (DBCLS), CC BY-SA 2.1 Japan — the skeleton and femur geometry.
  • Gray's Anatomy: The Anatomical Basis of Clinical Practice, 42nd ed. (Standring, ed.), 2020 — bone counts by region; fusion of bones during growth.
  • Feldesman MR, Kleckner JG, Lundy JK. Femur/stature ratio and estimates of stature in mid- and late-Pleistocene fossil hominids. Am J Phys Anthropol 1990;83:359–372 — femur ≈ 26.7 % of stature.
  • Reilly DT, Burstein AH. The elastic and ultimate properties of compact bone tissue. J Biomech 1975;8:393–405 — cortical bone ~205 MPa in compression, ~135 MPa in tension.
  • Bergmann G et al. Hip contact forces and gait patterns from routine activities. J Biomech 2001;34:859–871 — 238 % BW walking, 251 % stairs up, 260 % stairs down.
  • Bergmann G, Graichen F, Rohlmann A. Hip joint loading during walking and running, measured in two patients. J Biomech 1993;26:969–990 — stumbling 720 % and 870 % BW.
  • Courtney AC, Wachtel EF, Myers ER, Hayes WC. Age-related reductions in the strength of the femur tested in a fall-loading configuration. J Bone Joint Surg Am 1995;77:387–395.
  • Koch JC. The laws of bone architecture. Am J Anat 1917;21:177–298; Wolff J. Das Gesetz der Transformation der Knochen, 1892; Culmann & von Meyer, 1866–67 — trabeculae along stress trajectories.
  • Frost HM. Bone "mass" and the "mechanostat": a proposal. Anat Rec 1987;219:1–9 — bone adapts to the strains it sees.
  • Pauwels F. Gesammelte Abhandlungen zur funktionellen Anatomie des Bewegungsapparates, 1965 — the hip joint and abductor force directions in single-leg stance.
  • Currey JD. Bones: Structure and Mechanics. Princeton, 2002; Ross MH, Pawlina W. Histology, 8th ed. — osteon and lamella dimensions; cortical vs trabecular bone.
  • Parfitt AM. Osteonal and hemi-osteonal remodeling: the spatial and temporal framework for signal traffic in adult human bone. J Cell Biochem 1994;55:273–286 — cutting and closing cones; turnover ~4 %/yr cortical, ~28 %/yr trabecular (via BioNumbers 109908).
  • US Department of Health and Human Services. Bone Health and Osteoporosis: A Report of the Surgeon General, 2004 — the adult skeleton is replaced about every 10 years.
  • Hedges REM, Clement JG, Thomas CDL, O'Connell TC. Collagen turnover in the adult femoral mid-shaft: modeled from anthropogenic radiocarbon tracer measurements. Am J Phys Anthropol 2007;133:808–816.
  • Manolagas SC. Birth and death of bone cells. Endocr Rev 2000;21:115–137 — BMU size and lifespan; osteoclast and osteoblast lifespans.
  • Buenzli PR, Pivonka P, Smith DW. Spatio-temporal structure of cell distribution in cortical bone multicellular units: a mathematical model. Bone 2011;48:918–926 — cutting cone 20–40 µm/day.
  • Buenzli PR, Sims NA. Quantifying the osteocyte network in the human skeleton. Bone 2015;75:144–150 — 42 billion osteocytes, 3.7 trillion projections, 23 trillion connections, 175,000 km.
  • Bonewald LF. The amazing osteocyte. J Bone Miner Res 2011;26:229–238 — osteocytes are 90–95 % of bone cells and can live for decades.
  • Weinbaum S, Cowin SC, Zeng Y. A model for the excitation of osteocytes by mechanical loading-induced bone fluid shear stresses. J Biomech 1994;27:339–360.
  • Hodge AJ, Petruska JA. Recent studies with the electron microscope on ordered aggregates of the tropocollagen molecule, 1963 — the 67 nm D-period and the gap/overlap zones.
  • Weiner S, Wagner HD. The material bone: structure–mechanical function relations. Annu Rev Mater Sci 1998;28:271–298 — platelet size and orientation.
  • Hughes JM, Cameron M, Crowley KD. Structural variations in natural F, OH and Cl apatites. Am Mineral 1989;74:870–876, via the Crystallography Open Database, entry 9001233 (public domain) — the lattice.
  • Shannon RD. Revised effective ionic radii. Acta Cryst A 1976;32:751–767 — Ca²⁺ radii.
  • Slater JC. Atomic shielding constants. Phys Rev 1930;36:57–64 — the orbital approximation used for the electron clouds.
  • Angeli I, Marinova KP. Table of experimental nuclear ground state charge radii. At Data Nucl Data Tables 2013;99:69–95 — ⁴⁰Ca 3.478 fm.
  • NIH Office of Dietary Supplements. Calcium — Health Professional Fact Sheet — 99 % of body calcium in bones and teeth.
  • Einhorn TA, Gerstenfeld LC. Fracture healing: mechanisms and interventions. Nat Rev Rheumatol 2015;11:45–54; Marsell R, Einhorn TA. The biology of fracture healing. Injury 2011;42:551–555 — the stages.
  • Einhorn TA. Enhancement of fracture-healing. J Bone Joint Surg Am 1995;77:940–956 — 5–10 % of fractures delayed or impaired.
  • Scolaro JA, Schenker ML, Yannascoli S et al. Cigarette smoking increases complications following fracture: a systematic review. J Bone Joint Surg Am 2014;96:674–681.

Act 01's bone atlas (71 entries, all 206 bones) draws on 124 sources — Gray's Anatomy (42nd ed.), Moore's Clinically Oriented Anatomy (8th ed.), OpenStax Anatomy & Physiology 2e (CC BY 4.0), Wikipedia (CC BY-SA 4.0), Radiopaedia (CC BY-NC-SA 3.0) and the papers named — each listed on its bone's card. Which triangle is which bone comes from the BodyParts3D element names; the thumbs' proximal and distal phalanges and the naviculars are added from the same source. The ear ossicles and the coccyx are not in this scan and are not drawn.

Skeleton and femur geometry: BodyParts3D, © The Database Center for Life Science, licensed CC BY-SA 2.1 Japan; the derived meshes are re-shared under the same licence. Apatite atom positions: Crystallography Open Database entry 9001233, public domain.

EDUCATION ONLY This page explains how bones work. It is not medical advice and cannot assess anyone's bones, injury or treatment — for a suspected fracture, bone pain or questions about bone health, see a doctor.Not medical advice — for an injury or bone pain, see a doctor.