Dr. Michael P. Gillespie

The adult human skeleton consists of 206 named bones. Infants have more bones because not all bones have fused. Axial skeleton – 80 bones Longitudinal axis (center of the body) Bones arranged along the axis: skull bones, auditory ossicles, hyoid bone, ribs, breastbone, and backbone Appendicular skeleton – 126 bones Upper and lower limbs (extremities), girdles (connect limbs to axial skeleton)

Skull Cranium8 Face14 Hyoid1 Auditory Ossicles6 Vertebral Column26 Thorax Sternum1 Ribs24 Total80

Pectoral (Shoulder) girdles Clavicle2 Scapula2 Upper limbs (extremities) Humerus2 Ulna2 Radius2 Carpals16 Metacarpals10 Phalanges28

Pelvic (hip) girdle Hip, pelvic, or coxal bones2 Lower limbs (extremities) Femur2 Fibula2 Tibia2 Patella2 Tarsals14 Metatarsals10 Phalanges28 Total126

Long Bones Short Bones Flat Bones Irregular Bones Sesamoid Bones Sutural

Depressions and Openings Sites allowing the passage of soft tissue (nerves, blood vessels, ligaments, tendons) or formation of joints. Processes Projections or outgrowths on bone that form joints or attachment points for connective tissue, such as ligaments and tendons).

Fissure – narrow slit Foramen – opening (hole) Fossa – shallow depression (trench) Sulcus – furrow (groove) Meatus – tubelike opening (passageway)

Processes that form joints Condyle – Large, round protuberance at the end of a bone (knuckle) Facet – smooth, flat articular surface Head – rounded articular projection supported on the neck of a bone

Processes that form attachment points Crest – prominent ridge or elongated projection Epicondyle – projection above a condyle Line – long narrow ridge or border Spinous process – sharp, slender projection Trochanter – very large projection Tubercle – small, rounded projection Tuberosity – large, rounded projection

Carotid Hypoglossal Infraorbital Jugular Lacerum Magnum Mandibular

Mastoid Mental Olfactory Optic Ovale Rotundum Stylomastoid Supraorbital

Membrane-filles spaces between the cranial bones “soft spots” Allow the skull to change shape as it passes through the birth canal

Anterior fontanel Between the parietal bones and the frontal bone Posterior fontanel Between the parietal bones and the occipital bone Anterolateral fontanels Between the frontal, parietal, temporal, and sphenoid bones Posterolateral fontanels Between the parietal, occipital, and temporal bones

Kyphosis – exaggeration of the thoracic curve Lordosis – an exaggeration of the lumbar curve or cervical curve Lumbar spine stenosis – narrowing of the spinal canal Scoliosis – lateral bending of the vertebral column