Articulations

Articulations (Joints) Articulations – wherever 2 bones meet Classified by function –Synarthrosis (Immovable) –Amphiarthrosis (slightly movable) –Diarthrosis - (synovial or freely movable joints)

Synathrosis (no movement) Sutures –Bones of the skull Gomphosis –Ligament bonds tooth w/in bony socket

Amphiarthroses (Slightly Movable) Fibrous joint connected by ligament –Ex. Distal articulation between tibia and fibula Symphysis –Bones joined by disk of fibrocartilage –Ex. Vertebrae, between pubic bones Cartilaginous –Connection between rib and sternum

Angular Movements of Diarthrotic Synovial Joints –Angular Motion Flexion – reduces angle between articulating elements Extension - increases angle between articulating elements Adduction – moving towards midline Abduction – moving away from midline Circumduction – loop motion

Rotational Movements of Diarthrotic Synovial Joints Rotational

Special Movements –Inversion- turns sole of foot inward (opp-eversion) –Dorsiflexion- ankle flexion (plantar flexion pointed toe) –Opposition – grasping (thumb/fingers toward hand) –Protraction - move anterior across horizontal plane (opp retraction) –Elevation – move superior (opp depression)

Structural Classification of Synovial Joints Gliding – flat surfaces slide past one another –Ends of clavicles –Between carpals & tarsals –Between vertebrae Hinge – angular movement in a single direction –Occipital bone and atlas –Elbow, knee, ankle –Interphalangeal joints Pivot – permit rotation only –Atlas and axis –Proximal radius and ulna Ellipsodial – angular motion occurs in 2 planes –Radius w/proximal carpals –Phalanges w/metacarpals (and metatarsals) Saddle- permits angular motion but prevents rotation –thumb Ball and socket - round head rests within depression –Shoulder and hips

Double Jointed?

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