Human Osteology notes

Vocabulary flashcards covering directional terms, skull anatomy, vertebral column, ribs, sternum, pelvis, and the upper and lower limbs.

Osteology

The study of bones and the skeleton, central to biological anthropology.

Bone as living tissue

Bone is alive and dynamic, responding to stress, muscle action, disease, trauma, and nutrition.

Superior (cranial)

Toward the top of the body; the upper part.

Inferior (caudal)

Toward the bottom; the lower part.

Anterior (ventral)

Toward the front of the body.

Posterior (dorsal)

Toward the back of the body.

Medial

Toward the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Nearest to the torso or origin of a limb.

Distal

Farthest from the torso or origin of a limb.

Cranial

Relating to the skull.

Cranium

The skull; the bones of the head including the braincase.

Calvarium

The skull cap; the upper portion of the skull forming the brain case.

Mandible

The lower jaw; in humans formed by fused left and right dentary bones.

Maxilla

The upper jaw bone bearing the upper teeth; articulates with other facial bones.

Incisors

Front teeth used for cutting; two per quadrant in adults.

Canines

Pointed teeth next to incisors used for tearing; one per quadrant in adults.

Premolars

Teeth behind canines; typically two per quadrant in adults.

Molars

Back teeth used for grinding; three per quadrant in humans.

Dental formula

Shorthand notation for tooth types per mouth quadrant; humans: 2 incisors, 1 canine, 2 premolars, 3 molars (2:1:2:3).

Foramen

A hole in a bone; plural is foramina.

Sutures

Lines where cranial bones meet; they fuse with age.

Coronal suture

Suture between the frontal bone and the parietal bones.

Sagittal suture

Suture between the two parietal bones.

Lambdoidal suture

Suture between the occipital and parietal bones.

Squamosal suture

Suture between the temporal bone and the parietal bone.

Hyoid bone

A U-shaped bone in the neck that floats and serves as an origin for tongue muscles; does not articulate with other bones.

Postcranial

All bones of the skeleton except the skull.

Axial skeleton

The central axis: vertebral column, ribs, and sternum.

Appendicular skeleton

The limbs and girdles (pectoral and pelvic).

Vertebral column

The backbone; vertebrae supported by discs that protects the spinal cord.

Atlas (C1)

First cervical vertebra; supports the skull and lacks a true body.

Axis (C2)

Second cervical vertebra; bears the dens for rotation of the head.

Dens

Odontoid process of the axis; acts as a pivot for the atlas.

Transverse foramen

Opening in cervical vertebrae for the vertebral artery.

Cervical vertebrae

Neck vertebrae (C1–C7) with transverse foramina.

Thoracic vertebrae

Vertebrae that articulate with ribs via rib facets.

Lumbar vertebrae

Lower back vertebrae; large bodies, short spinous processes; no rib facets.

Sacrum

Five fused sacral vertebrae; articulates with the pelvis.

Coccyx

Small tail-like bone formed by fused coccygeal vertebrae.

Ribs

Twelve pairs of ribs articulating with thoracic vertebrae; connected to sternum by costal cartilage.

Costal cartilage

Cartilage connecting ribs to the sternum, providing flexible articulation.

Floating ribs

Ribs 11–12 that do not attach to the sternum.

Sternum

Flat breastbone consisting of manubrium, body, and xiphoid process.

Manubrium

Superior segment of the sternum.

Body (sternum)

Central portion of the sternum.

Xiphoid process

Inferior end of the sternum; often fuses with the body in adults.

Innominate (pelvis)

Hip bone formed by ilium, pubis, and ischium; fused in adulthood.

Ilium

Broad, blade-like superior part of the innominate; palpable at the hip.

Pubis

Anterior portion of the innominate; meets the opposite side.

Ischium

Posterior inferior portion of the innominate; you sit on it.

Acetabulum

Hip socket where the femoral head articulates.

Pelvic girdle

Ring of bones comprising the pelvis that supports the trunk and attaches to the legs.

Femur

The thigh bone; largest bone in the body; ball-and-socket hip joint.

Femoral head

Rounded proximal end of the femur that fits into the acetabulum.

Linea aspera

Ridge along the posterior femur; origin for the hamstring muscles.

Lesser trochanter

Proximal medial projection on the femur for muscle attachment.

Patella

Kneecap; sesamoid bone within the quadriceps tendon that enhances knee leverage.

Tibia

Large medial bone of the lower leg; articulates with femur and fibula.

Tibial plateau

Proximal articulation surface of the tibia with the femur.

Tibial tuberosity

Roughened area where the quadriceps tendon attaches.

Anterior crest

Prominent ridge along the front of the tibia.

Medial malleolus

Medial ankle projection formed by the distal tibia.

Fibula

Long, slender lateral bone of the lower leg; stabilizes the ankle.

Lateral malleolus

Distal end of the fibula forming the outer ankle bump.

Tarsals

Seven bones of the ankle that form the tarsus; includes the calcaneus.

Calcaneus

Heel bone; largest tarsal.

Metatarsals

Five long bones in the sole of the foot; numbered 1–5.

Phalanges (toes)

Toe bones; the big toe has two phalanges; digits 2–5 have three.

Glenoid fossa

Articular surface of the scapula that contacts the humeral head.

Scapular spine

Raised ridge on the posterior surface of the scapula.

Acromion process

Projection of the scapula forming part of the shoulder; articulates with the clavicle.

Coracoid process

Hook-like projection on the scapula for muscle attachment.

Scapula

Shoulder blade; flat, triangular bone on the back of the thorax.

Clavicle

S-shaped collarbone connecting the sternum to the scapula; strong ligaments make it rarely dislocated.

Deltoid tuberosity

Roughened area on the humerus where the deltoid muscle attaches.

Olecranon fossa

Posterior depression on the humerus where the ulna fits during elbow extension.

Medial epicondyle

Medial bump on the distal humerus; attachment for forearm muscles.

Trochlea

Pulley-like distal articular surface of the humerus that articulates with the ulna.

Capitulum

Rounded distal articular surface of the humerus that articulates with the radius.

Radius

Lateral forearm bone; allows forearm rotation; has a rounded proximal head.

Radial notch

Medial concave surface on the ulna that accommodates the radial head.

Ulnar notch

Distal concave surface on the radius that articulates with the ulna.

Pronation

Rotation that crosses the radius over the ulna; palm faces downward.

Supination

Returning the forearm to the anatomical position; radius uncrosses.

Carpal bones

Eight small wrist bones forming the carpus.

Metacarpals

Five long bones in the palm; numbered 1–5 from thumb to little finger.

Phalanges (hands)

Finger bones; each finger has proximal, middle, and distal phalanges; thumb lacks a middle phalanx.