How the body comes apart.
Anatomy Studio takes the open Z-Anatomy model, 2,270 named pieces across ten systems, and separates it the way an engineering exploded view separates a machine: the skeleton stays put as the axis, and every other system moves outward by layer. Eighteen structures can be opened on their own. The studio opens in X-ray, with the skeleton solid and every other system translucent; switch to Realistic, Colour-coded or Clay in the Finish panel.
Ten systems, one frame
Every piece belongs to one asset file, loaded in three stages. The core stage (skeleton, ligaments and discs, viscera, heart, brain and sense organs) loads first; the muscles follow; vessels, nerves, lymphatics and skin regions load last. Phones stop after the core stage and offer a button for the rest.
| System | Pieces | What is individual | What is merged |
|---|---|---|---|
| Skeleton | 277 | Every bone, tooth, sesamoid, costal, laryngeal, nasal and ear cartilage | Nothing |
| Ligaments & discs | 146 | 23 intervertebral discs (annulus + nucleus), spinal ligaments, knee menisci and cruciates, articular discs | Other ligaments of a joint into that joint, per side |
| Viscera | 118 | Every organ, lung lobe, lobar and segmental bronchus, gland and duct | Nothing |
| Heart | 40 | Four chambers, nine valve leaflets, papillary muscles, coronary arteries and cardiac veins, great vessels | Nothing |
| Brain & senses | 178 | Gyri and lobules, deep nuclei, ventricles, commissures, brainstem parts, cerebellar lobules, meninges, eye and inner-ear parts | Cortical sulci per hemisphere, brainstem nuclei per side, lacrimal apparatus, outer and middle ear |
| Muscles | 522 | Every muscle and named muscle head or part | Fasciae, bursae and tendon sheaths into their regional group, per side |
| Arteries & veins | 623 | Named vessels to the seventh level of the vascular tree | Deeper twigs into their parent vessel |
| Nerves & cord | 234 | Cranial nerves, plexus trunks and named nerves to the sixth level | Branches into their parent nerve; spinal tracts into white and grey matter |
| Lymphatics | 67 | Spleen, thymus, tonsils, larger node groups | Individual nodes into regional groups |
| Female reproductive · schematic | 10 | Uterus, cervix, vagina, uterine tubes, ovaries, female urethra, mammary glands (built for the studio, not from the source model) | Nothing |
| Surface regions | 65 | Regional groups of skin, rendered translucent | Sub-regions into their group, per side |
Piece counts come from manifest.json and are regenerated by the build. Names follow Terminologia Anatomica as used by Z-Anatomy; a side in brackets marks left and right pieces.
The exploded view
The slider moves every piece along a fixed vector, so any position between assembled and fully separated is a legitimate view, and reassembly is exact. Each system has its own rule so the separation reads anatomically rather than as a random scatter.
Skeleton stays as the axis
Bones, discs and ligaments move only a few centimetres. Everything else is measured outward from the trunk axis, or from the axis of the limb the piece belongs to.
Muscles by depth
Each muscle moves radially away from its axis; superficial muscles travel farther than deep ones, so the layers open like a dissection. Limb muscles also move away from the trunk.
Viscera forward, brain up
Organs of the thorax and abdomen move forward and slightly down; the heart sits in front of the lungs. The brain lifts out of the skull; the eyes come forward and outward.
Vessels, nerves, lymph, skin
Arteries move laterally and forward, veins laterally and back, nerves back and outward, lymphatics forward. Skin regions travel farthest, as a translucent outer shell. Over the last part of the slider a gentle fan de-clumps the small pieces.
Eighteen nested studies
Each study hides everything except its members and replaces the whole-body vectors with its own. Labels appear once the structure is open, and “Label every piece” names all of them. If the studio is in X-ray, a study renders in the realistic finish and returns to X-ray when you leave it. The eye, hand, knee, shoulder and foot studies have a Left / Right toggle (also ?side=R in the link). Press the same button, Esc or Return to the body to reassemble.
Heart · 40 pieces
Chambers part along the septa: atria lift, ventricles drop. The nine valve leaflets hang in the gaps they seal, papillary muscles follow their ventricle, coronary arteries pull forward and cardiac veins pull back as two cages, and the great vessels extend along their course.
Open the heart →Lungs · 56 pieces
Two lobes on the left and three on the right fan away from the mediastinum. The trachea and the full bronchial tree stay, with each lobar and segmental bronchus nudged toward its lobe. The pleura lifts clear as a translucent envelope; pulmonary vessels follow their lobe.
Open the lungs →Spine · 62 pieces
Atlas to coccyx stack apart along the column's own curve with widening gaps, each disc held between its vertebrae. The anterior longitudinal ligament peels forward, the posterior ligaments back, and the spinal cord, its grey matter, central canal and dural sac slide out behind the canal.
Open the spine →Brain · 147 pieces
The cortex opens outward as a shell of named gyri, lobe by lobe, leaving white matter, deep nuclei and the ventricles at the centre. The corpus callosum lifts, the cerebellum drops back, and the brainstem descends as midbrain, pons and medulla. Dura goes translucent.
Open the brain →Skull · 70 pieces
The vault lifts away bone by bone with the sphenoid left at the centre as the keystone. Facial bones and nasal cartilages come forward, the maxillae carry the upper teeth, the mandible drops with the lower teeth and hyoid, and the ossicles pull out of each temporal bone.
Open the skull →Eye · 11 pieces
Either eye opens along its optic axis: cornea, anterior chamber, iris and lens step forward, the vitreous stays, and the retina and sclera fall back. The lacrimal apparatus sits off to the side.
Open the eye →Hand · 39 pieces
Eight carpals fan from the wrist, the metacarpals and phalanges stretch down each digit in steps, the thumb swings out, and the thenar, hypothenar, interosseous and lumbrical muscles peel off the palm.
Open the hand →Knee · 18 pieces
Femur up, tibia and fibula down, patella forward. The menisci slide apart, the cruciates separate front and back, the collateral ligaments swing outward, and the capsule stays as a translucent envelope.
Open the knee →Rib cage · 47 pieces
Twelve pairs of ribs swing outward from the spine, upper ribs rising and lower ribs dropping, with the costal cartilages carried forward and the sternum lifted clear in front.
Open the rib cage →Digestive tract · 44 pieces
Mouth and salivary glands up, pharynx and oesophagus back, stomach left, small intestine forward, colon around the outside. The liver opens into its eight segments; the pancreas and its ducts drop behind the stomach.
Open the digestive tract →Urinary system · 10 pieces
Kidneys apart with the adrenals lifted off their poles, renal pelvis drawn out of each hilum, ureters down to the bladder, bladder and urethra forward out of the pelvis.
Open the urinary system →Face · 36 pieces
Muscles of expression lift off in the layers they occupy, scalp up, eye and nose forward, mouth forward and down; temporalis, masseter and the pterygoids swing out to the sides. The skull stays as reference.
Open the face →Aorta · 74 pieces
The aorta stays as the trunk while every branch pulls away toward what it serves: renal arteries out, coeliac and mesenteric trees forward, segmental arteries back, the iliac system down into the pelvis.
Open the aorta →Pelvis · 12 pieces
Hip bones swing outward from the sacrum, which lifts back with the coccyx; the pubic symphysis drops forward and the pelvic ligaments lift clear.
Open the pelvis →Shoulder · 16 pieces
Humerus out of the glenoid, clavicle up, the four rotator-cuff muscles in the directions they act, the three parts of the deltoid open as a cap. Left or right.
Open the shoulder →Larynx · 33 pieces
Hyoid and epiglottis up, thyroid cartilage forward, cricoid down, arytenoids back; the vocal muscles fan out with the membranes translucent between them; the thyroid gland drops forward.
Open the larynx →Foot · 42 pieces
Talus off the calcaneus, the midfoot spread in the arch, metatarsals and toes forward in steps, extensors up off the dorsum and the plantar layers down. Left or right.
Open the foot →Female reproductive system · 10 pieces · schematic
Z-Anatomy ships a single base body with a male reproductive system and no female geometry, so this study is a reconstruction built for the studio from textbook dimensions: uterus, cervix, vagina, uterine tubes with fimbriae, ovaries and a female urethra in the pelvis, plus mammary glands on the chest. The Reproductive system switch (Male / Female) swaps the two sets; skeleton, muscles, vessels, nerves and skin are the same shared body in both.
Open the female reproductive system →Inspecting pieces
Click any piece, or search the list by name, system, region or hierarchy. The inspector shows the Z-Anatomy description (from Wikipedia, trimmed), the hierarchy path, the bounding size, the triangle count and, for merged pieces, the structures that were folded in. Isolate frames the piece alone; the all-parts board shows every loaded piece individually scaled on one non-overlapping grid.
Descriptions are matched by name with fallbacks (dropping side, qualifier or the “of …” clause, then the parent structure). About 89 % of pieces match a specific article; the rest show their parent's or system's text. Treat all text as teaching material, not clinical guidance.
How it was built
Z-Anatomy ships one FBX file per system, exported from Blender with a naming convention: .l/.r sides, .g group empties for the hierarchy, and small placeholder meshes for labels. A headless Blender 4.5 script imports each file, drops the placeholders and muscle-attachment overlays, joins small structures into their parent, decimates each system to a triangle budget, centres each piece on its bounds and exports one GLB per system with the anatomical metadata as glTF extras. A gltf-transform step welds, quantises and meshopt-compresses the files and writes the manifest. Total: about 4.6 million triangles in 32 MB, with vessels and nerves kept individual to the seventh and sixth levels of their trees. Rendering adds ground-truth ambient occlusion on desktop and procedural surface detail (bone grain, muscle fibres, organ vasculature, skin pores) generated in the browser. A second, undecimated tier of the same pieces (8.4 million triangles, 55 MB across ten files) streams in per system whenever a piece grows large on screen, so the closer you zoom, the finer every piece becomes; the Zoom detail toggle controls it.
The runtime is plain ES modules on three.js 0.180 with no build step, the same engine family as the Model S Studio. A Playwright suite checks the piece counts, explosion and exact reassembly, each nested study, the board layout, the mobile layout and reduced motion.
Credits & licence
Model and descriptions: Z-Anatomy by Gauthier Kervyn, Lluís Vinent Juanico and contributors, CC BY-SA 4.0. The adapted 3D assets, manifest and description text on this site are shared under the same licence; see ASSET-LICENSE.txt. Studio code: jez237-site on GitHub. three.js is MIT licensed.