Joint Types

Fibrous Joints - articulating bones are united by dense irregular connective tissue; immovable to slightly moveable; no cartilage

Cartilaginous Joints - a solid piece of hyaline cartilage or fibrous cartilage that unites the articulating bones; immovable to slightly moveable; ex) intervertebral disk

Synovial joints - two-layered articular capsule that unites the articulating bones and surrounds a lubricated space called an articular cavity; slightly moveable to freely moveable; most of the joints in your body; diarthrosis

Functional Classifications

• Synarthroses

  • allow no movement

  • ex. suture, epiphyseal plate

• Amphiarthroses

  • Allow little movement

  • Ex. Pubic symphysis, intervertebral discs, interosseous membrane

• Diarthroses

  • Freely moveable

  • commonly covered by fluid filled capsule

  • Ex. hip, knee, shoulder, elbow

Fibrous Joint Subtypes

Sutures - fibrous joint composed of a thin layer of dense irregular connective tissue; sutures occur only between bones of the skull; covered by a layer of osteogenic cells (cambial layer) overlaid by a capsular lamella of fibrous tissue which is continuous with the periosteum

Synostosis - complete fusion of two separate bones into one; present during growth, replaced by bone as an adult

Frontal suture - a suture persisting past age 6 that is immovable

Syndesmosis (& interosseous membranes) - fibrous joint that consists of bundles of dense connective tissue fibers (collagen) that connect the bones; synarthroses or amphiarthrosis

Cartilaginous Joints Subtypes

Synchondrosis - cartilaginous joint in which the connecting material is a solid piece of cartilage that allows little or no movement (synarthroses); articulating bones are lightly connected by hyaline cartilage or fibrous cartilage; ex) first rib and the manubrium of the sternum, epiphyseal cartilages; adjacent bone tends to undergo synostosis (fusion) when growth is complete

Symphysis - cartilaginous joint in which the ends of the articulating bones are covered with hyaline cartilage and a broad flat disc of fibrous cartilage connects the bones; amphiarthrosis and present in the midline joints

Synovial Joints Subtypes

Plane Joint - flat or slightly curved surfaces that are primarily back and forth and side to side movements, but may rotate; biaxial, ex) 2nd and 3rd cuneiforms of tarsus in foot

Hinge joints - convex surface of one bone into a concave surface of another; angular, opening and closing motion (flexion-extension movement), uniaxial, ex) elbow

Pivot Joints - rounded or pointed surface of one bone articulates with a ring formed by bone and ligament; uniaxial with rotation around its longitudal axis; ex) radioulnar joints

Condylar Joint - oval shaped projection/depression pairing, movement around 2 axes (restricted rotation), biaxial (abduction-adduction, flexion-extension); radius and scaphoid bones of wrist

Saddle Joint - saddle-shaped surface pairing with biaxial movements, ex) Sternoclavicular joint; between trapezium of wrist and metacarpal of thumb

Ball-and-Socket Joints - triaxial movements, ex) acetabulum of hip bone and femur head