This lab finishes the axial skeleton below the skull: the vertebral column, the sternum, the ribs, and the hyoid bone. On the lab practical you will be handed loose vertebrae, an articulated column, a rib, or a sternum and asked to name a part or decide which region a bone came from. This review teaches each structure with a "where it is / how to spot it" table, then drills it with numbered pins and a timed practical.
Your lab manual wins. Lab sections vary in which models, slides, and terms they use. If anything here differs from your lab handout or what your instructor emphasized, go with your lab material and tell your tutor so this review can be updated.
Vertebral Column
The adult vertebral column has 26 bones: 24 separate vertebrae (7 cervical, 12 thoracic, 5 lumbar) plus the sacrum and the coccyx. A memory trick for the counts: breakfast at 7, lunch at 12, dinner at 5. On the articulated model, read the column top to bottom and watch the bodies get bigger — they carry more weight the lower they sit.
| Region | Bones | Where | How to identify it |
|---|---|---|---|
| Cervical | 7 vertebrae (C1–C7) | Neck | Smallest bodies; a hole (transverse foramen) in each transverse process |
| Thoracic | 12 vertebrae (T1–T12) | Chest; one pair of ribs per vertebra | Costal facets for the ribs; long spinous processes |
| Lumbar | 5 vertebrae (L1–L5) | Lower back | Biggest, thickest bodies; no transverse foramina and no costal facets |
| Sacrum | 5 fused vertebrae (S1–S5) | Back of the pelvis, between the hip bones | Triangular bone with paired sacral foramina |
| Coccyx | 3–5 small fused vertebrae | Tip of the column (tailbone) | Tiny segments hanging from the apex of the sacrum |
Seen from the side, a healthy adult column is an S-shaped spring. The two primary curves (thoracic and sacral) are left over from the C-shaped spine of a fetus. The two secondary curves (cervical and lumbar) develop after birth as the baby lifts its head and later stands.
| Curvature | Which way it bows | Primary or secondary | When it appears |
|---|---|---|---|
| Cervical | Convex anteriorly (bows forward) | Secondary (compensation) curve | When an infant starts holding up the head (about 3–4 months) |
| Thoracic | Concave anteriorly (bows backward) | Primary (accommodation) curve | Present before birth |
| Lumbar | Convex anteriorly (bows forward) | Secondary (compensation) curve | When a child starts standing and walking (about 1 year) |
| Sacral | Concave anteriorly (bows backward) | Primary (accommodation) curve | Present before birth |
Intervertebral discs are pads of fibrocartilage between the bodies of neighboring vertebrae, from C2–C3 down to L5–S1 (there is no disc between C1 and C2). Each has a tough outer ring, the anulus fibrosus (many books spell it annulus; both are fine), around a soft, gel-like center, the nucleus pulposus. Discs absorb shock and let the column bend. Intervertebral foramina are the side openings between neighboring vertebrae, made by the notches above and below each pedicle; spinal nerves leave the column through them.
The sacrum is five vertebrae fused into one triangle. Its broad base faces up to meet L5; its narrow apex points down to the coccyx. Turn it over to tell the surfaces apart: the anterior (pelvic) surface is smooth and concave with large foramina, and the posterior surface is rough and bumpy with a midline crest.
| Structure | Where | How to identify it |
|---|---|---|
| Sacral promontory | Anterior edge of the base (top of S1) | The front lip of the sacrum that juts forward |
| Ala (plural alae) | Wing on each side of the base | Smooth, flared surface lateral to the promontory |
| Transverse lines | Anterior surface | Horizontal ridges where the five sacral vertebrae fused |
| Anterior sacral foramina | Anterior surface, 4 pairs | Larger holes at the ends of the transverse lines |
| Median sacral crest | Posterior midline | Bumpy ridge = fused spinous processes |
| Posterior sacral foramina | Posterior surface, 4 pairs | Smaller holes on either side of the median crest |
| Sacral canal | Inside the sacrum, opening at the base | Continuation of the vertebral canal |
| Sacral hiatus | Lower end of the posterior surface | Inverted-U gap where the canal opens at the bottom |
| Auricular surface | Upper lateral surface | Ear-shaped surface that forms the sacroiliac joint with the hip bone |
| Coccyx | Below the apex of the sacrum | 3–5 tiny fused vertebrae; the tailbone |
Label It · Column & sacrum
Click a numbered pin (or its row), choose the structure it points to, then press Check answers. Wrong answers show the correction in green.
A Typical Vertebra
Every movable vertebra below C1 follows the same plan, so learn it once. The body carries weight. Behind it, the vertebral arch (two pedicles + two laminae) wraps around the vertebral foramen, where the spinal cord runs. Seven processes stick out of the arch: one spinous process, two transverse processes, two superior articular processes, and two inferior articular processes. The articular processes link each vertebra to the ones above and below.
| Part | Where | How to identify it |
|---|---|---|
| Body | Anterior, weight-bearing part | Thick drum or disc of bone; discs sit on its upper and lower surfaces |
| Pedicle (×2) | Short bar from the back of the body | The "foot" of the arch; its notches form the intervertebral foramen |
| Lamina (×2) | From the pedicle to the midline | Flat plate; the two laminae meet to form the roof of the arch |
| Vertebral arch | Behind the body | Pedicles + laminae together; it encloses the vertebral foramen |
| Vertebral foramen | Between body and arch | Big hole for the spinal cord; stacked foramina form the vertebral canal |
| Transverse process (×2) | Projects laterally at the pedicle–lamina junction | Side "arms" for muscle and (thoracic) rib attachment |
| Spinous process | Projects posteriorly from where the laminae meet | The single midline "spine" you feel down your back |
| Superior articular process (×2) | Points upward from the arch | Its facet faces backward (posteriorly) in thoracic vertebrae |
| Inferior articular process (×2) | Points downward from the arch | Its facet faces forward to meet the vertebra below |
| Inferior vertebral notch | Below the pedicle | Deep notch; with the superior notch of the vertebra below it makes the intervertebral foramen |
Model tip: to orient a loose vertebra, put the body toward you (anterior) and the spinous process away from you, then look down from above. Pedicles are the short "legs" from the body; laminae are the plates that meet at the spinous process. In a lateral view, the deep notch under the pedicle is the inferior vertebral notch — stack two vertebrae and you will see it become an intervertebral foramen.
Label It · Vertebra parts
Click a numbered pin (or its row), choose the structure it points to, then press Check answers. Wrong answers show the correction in green.
Regional Features
On the practical you will often get one loose vertebra and a single question: which region? Work through three checks in order: (1) Is there a hole in each transverse process? → cervical. (2) Are there smooth costal facets on the body and transverse processes? → thoracic. (3) Neither, and the body is huge? → lumbar. Then look for the special vertebrae: the atlas, the axis, and C7.
| Vertebra | Body | Vertebral foramen | Spinous process | Giveaway features |
|---|---|---|---|---|
| Typical cervical (C3–C6) | Small, oval | Large, triangular | Short, bifid (forked) | Transverse foramen in each transverse process (for the vertebral artery) |
| Atlas (C1) | None | Very large ring | None (small posterior tubercle) | Anterior and posterior arches; large superior articular facets hold the occipital condyles (nodding "yes") |
| Axis (C2) | Body topped by the dens | Large | Large, bifid | The dens (odontoid process) is the pivot the atlas turns around (shaking "no") |
| C7 (vertebra prominens) | Small | Triangular | Long, not bifid | The bump you feel at the base of your neck |
| Thoracic | Medium, heart-shaped | Small, round | Long, slender, slants sharply down | Costal facets on the body (superior and inferior demifacets) and on the transverse processes (T1–T10) |
| Lumbar | Largest, kidney-shaped | Triangular | Short, thick, hatchet-shaped | No transverse foramina, no costal facets; massive body |
Atlas vs. axis on the model: the atlas is a ring with no body and no spinous process; its kidney-shaped superior facets cradle the occipital condyles. The axis is the one with the upright tooth, the dens (odontoid process), which fits into the front of the atlas ring. Together they form the atlantoaxial joint you use to shake your head "no."
Label It · Vertebra ID
Click a numbered pin (or its row), choose the structure it points to, then press Check answers. Wrong answers show the correction in green.
Sternum, Ribs & Hyoid
The thoracic cage is the thoracic vertebrae behind, the sternum in front, and 12 pairs of ribs with their costal cartilages in between. Left and right are always the specimen's: in an anterior view, the ribs on your left side of the picture are the body's right ribs.
| Structure | Where | How to identify it |
|---|---|---|
| Manubrium | Top part of the sternum | Widest part; shaped like a necktie knot |
| Jugular (suprasternal) notch | Top center of the manubrium | The dip you feel at the base of your throat |
| Clavicular notch (×2) | Upper lateral corners of the manubrium | Shallow notches where the clavicles articulate |
| Sternal angle | Junction of manubrium and body | Horizontal ridge at the level of rib 2 — start counting ribs here |
| Body | Middle, longest part | Long flat blade with notches for the cartilages of ribs 2–7 |
| Xiphoid process | Bottom tip | Small pointed tip; cartilage that ossifies with age |
| Group | Ribs | Anterior attachment |
|---|---|---|
| True ribs (vertebrosternal) | 1–7 | Each has its own costal cartilage that reaches the sternum |
| False ribs (vertebrochondral) | 8–10 | Cartilages join the cartilage of the rib above (costal margin), not the sternum directly |
| Floating ribs (vertebral) | 11–12 | No anterior attachment at all |
Two naming conventions. Many courses (and the KCE week 9 study guide) list true ribs 1–7, false ribs 8–10, and floating ribs 11–12. The Martini textbook calls all of ribs 8–12 false ribs, with 11–12 as the floating subgroup. Both are correct. If a station asks "true, false, or floating?" for rib 11 or 12, "floating" is the most specific answer.
| Structure | Where | How to identify it |
|---|---|---|
| Head | Posterior (vertebral) end | Wedge with two small facets; articulates with the bodies of thoracic vertebrae |
| Neck | Just lateral to the head | Short narrow stretch between head and tubercle |
| Tubercle | Neck–shaft junction, posterior surface | Small knob with a facet for the transverse costal facet |
| Angle | Just lateral to the tubercle | Where the shaft bends sharply forward |
| Shaft (body) | Most of the rib | Long, thin, curved, flattened blade |
| Costal groove | Inferior border of the shaft, inner surface | Channel that shelters the intercostal nerve, artery, and vein |
| Costal cartilage | Anterior end of the rib | Hyaline cartilage bar linking the rib toward the sternum |
The hyoid is a U-shaped bone in the front of the neck, between the mandible and the larynx. It is the only bone in the body that does not articulate with another bone; it hangs from the styloid processes of the temporal bones by ligaments and anchors muscles of the tongue and throat.
| Structure | Where | How to identify it |
|---|---|---|
| Body | Front of the U | Curved central bar, in the neck just above the larynx |
| Greater horns (cornua) | Extending back from each end of the body | Long, tapering arms |
| Lesser horns (cornua) | Where the body meets each greater horn | Small cones pointing upward (attach the stylohyoid ligaments) |
Label It · Sternum & ribs
Click a numbered pin (or its row), choose the structure it points to, then press Check answers. Reminder: this is an anterior view, so the ribs on your left are the specimen's right ribs.
Label It · Rib & hyoid
Click a numbered pin (or its row), choose the structure it points to, then press Check answers. Wrong answers show the correction in green.
Check Yourself
Rapid Recall
Say the answer out loud, then tap the card to check. Shuffle and go again until every card is automatic.
Practical Simulation
This runs like a real lab practical: one pinned structure or question per station, a timer, and you type the answer — no word bank. Each attempt draws 25 stations at random from a pool of 69 covering the column, every vertebra type, the sacrum, the sternum, the ribs, and the hyoid. Spell names fully; common synonyms (e.g., "odontoid process," "suprasternal notch," "annulus fibrosus," "cornu") are accepted.
25 stations · 60 seconds each · stations come in random order every attempt.
| # | Station | Your answer | Correct |
|---|
Watch Out
| The mistake | The fix |
|---|---|
| Calling the vertebral foramen the "intervertebral foramen" (or the reverse). | Vertebral foramen = the big hole in ONE vertebra for the spinal cord. Intervertebral foramen = the side gap BETWEEN two vertebrae for a spinal nerve. |
| Mixing up the transverse foramen with the transverse costal facet. | Foramen = a hole (cervical). Facet = a smooth joint surface (thoracic, for the rib tubercle). |
| Calling a big thoracic vertebra "lumbar." | Check for costal facets first. Any facet on the body = thoracic, no matter the size. |
| Swapping pedicle and lamina. | Pedicles attach to the body (think "foot"); laminae are the plates that meet behind at the spinous process. |
| Swapping atlas and axis. | Atlas = ring, no body. Axis = the one with the dens sticking up. |
| Reading the sacrum upside down or backward. | The wide base goes up. The smooth concave side with big foramina is anterior; the bumpy crest is posterior. |
| Calling the sternal angle the "xiphoid" or the jugular notch the "sternal angle." | Jugular notch = top of the manubrium. Sternal angle = manubrium–body ridge (rib 2). Xiphoid = bottom tip. |
| Mixing up the rib's head and tubercle. | Head = the very end, meets the vertebral body. Tubercle = the knob a little farther out, meets the transverse process. |
| Reading left and right from your own point of view. | Left and right always mean the specimen's. In an anterior view the specimen's right is on your left. |
Cheat Sheet
Print it or screenshot it for a last look before the lab.
| Topic | Know this |
|---|---|
| Column totals | 26 bones: 7 C, 12 T, 5 L, sacrum (5 fused), coccyx (3–5 fused) |
| Curvatures | Cervical and lumbar = secondary, convex anteriorly. Thoracic and sacral = primary, concave anteriorly |
| Discs | Fibrocartilage between bodies, C2–C3 to L5–S1; anulus fibrosus + nucleus pulposus; none between C1 and C2 |
| Typical vertebra | Body; vertebral arch (pedicles + laminae); vertebral foramen; spinous, transverse, superior and inferior articular processes |
| Intervertebral foramen | Inferior vertebral notch + superior vertebral notch of the next vertebra; spinal nerves exit |
| Cervical | Transverse foramina (vertebral arteries); bifid spinous C2–C6; large triangular vertebral foramen |
| C1 / C2 / C7 | Atlas: no body, no spinous, anterior and posterior arches. Axis: dens. C7: vertebra prominens |
| Thoracic | Heart-shaped body; costal facets (body) + transverse costal facets; long spinous process slanting down |
| Lumbar | Massive body; short hatchet spinous process; no foramina, no costal facets |
| Sacrum, anterior | Promontory, alae, transverse lines, anterior sacral foramina |
| Sacrum, posterior/lateral | Median sacral crest, posterior sacral foramina, sacral canal, sacral hiatus; auricular surface (sacroiliac joint) |
| Sternum | Manubrium (jugular notch, clavicular notches) → sternal angle (rib 2) → body → xiphoid process |
| Rib groups | True 1–7 (vertebrosternal); false 8–10 (vertebrochondral); floating 11–12 (vertebral) |
| Rib parts | Head, neck, tubercle, angle, shaft, costal groove (inferior border), costal cartilage |
| Hyoid | Body, greater horns, lesser horns; articulates with no other bone |
Debrief
You have now covered the vertebral column, the sternum, the ribs, and the hyoid. Next, Lab 6 moves to the appendicular skeleton with the pectoral girdle and upper limb. Lab Exam 2 follows Labs 4–7.
💭 Before the real thing: run the practical simulation until you score 90% or better twice in a row. Then do it once with the timer on.