Skeletal System Exam

Axial Skeleton

Consists of the bones that lie around the longitudinal axis of the human body.

Appendicular Skeleton

Consists of the bones of the upper and lower limbs (extremities), plus the bones forming the girdles that connect the limbs to the axial skeleton.

Long Bones

Greater length than width; slightly curved for strength; compact bone in diaphysis & spongy bone in epiphyses.

Short Bones

Cube shaped; equal in length and width; spongy bone with compact on outer surface.

Flat Bones

Thin, composed of two nearly parallel plates of compact bone with a layer of spongy in between; protection and muscle attachment site.

Irregular Bones

Complex shaped; vary in the amount of spongy and compact bone.

Sesamoid Bones

Develop in certain tendons where there is considerable friction, tension, and physical stress.

Bone Surface Markings

Structural features adapted for specific functions; not present at birth - develop from tension and force.

Depressions & Openings

Allow the passage of soft tissues or form joints.

Processes

Projections or outgrowths that either help form a joint or serve as attachment sites.

Fissure

Narrow slit between adjacent parts of bones through which blood vessels and nerves pass.

Foramen

Opening through which blood vessels, nerves, or ligaments pass.

Fossa

Shallow depression.

Sulcus

Furrow along bone surface that accommodates blood vessels, nerves, or tendons.

Meatus

Tube-like opening.

Condyle

Large, round protuberance with smooth articular surface at the end of the bone.

Facet

Smooth, flat, slightly concave or convex articular surface.

Head

Usually rounded articular projection supported on neck (constricted portion) of bone.

Crest

Prominent ridge or elongated projection.

Epicondyle

Typically roughened projection above condyle.

Line

Long, narrow ridge or border (less prominent than crest).

Spinous Process

Sharp, slender projection.

Spine

A sharp, pointed, narrow process.

Trochanter

Very large projection.

Tubercle

Variably sized rounded projection.

Tuberosity

Variable sized projection that has a rough, bumpy surface.