Chapter 8 – Joints (Articulations)

A set of vocabulary flashcards covering the structural and functional classifications of joints, specific examples of fibrous and cartilaginous joints, types of synovial joints, and anatomical movement terms.

Fibrous Joints

Joints held together by dense connective tissue containing many collagen fibers; found in bones in close contact.

Cartilaginous Joints

Joints held together by hyaline cartilage or fibrocartilage.

Synovial Joints

Joints that have a complex structure including a joint capsule and synovial cavity; they allow the most movement.

Synarthrotic

A functional classification for joints that are immovable.

Amphiarthrotic

A functional classification for joints that are slightly movable.

Diarthrotic

A functional classification for joints that are freely movable.

Syndesmosis

A fibrous joint where bones are bound by a sheet or bundle of dense connective tissue (interosseous membrane or ligament); amphiarthrotic.

Suture

A fibrous joint where a thin layer of sutural ligament connects flat bones of the skull; synarthrotic.

Gomphosis

A fibrous joint consisting of a cone-shaped bony process in a socket, such as a tooth root in the maxilla or mandible; synarthrotic.

Synchondrosis

A cartilaginous joint where bands of hyaline cartilage unite bones; examples include the epiphyseal plate and the joint between the manubrium and the first rib.

Symphysis

A cartilaginous joint with a pad of fibrocartilage between bones and articular surfaces covered by hyaline cartilage; amphiarthrotic.

Articular Cartilage

Hyaline cartilage located on the ends of the articulating surfaces of bones.

Joint Capsule

An envelope consisting of a thick outer fibrous capsule of ligaments and an inner synovial membrane.

Synovial Fluid

Fluid that moistens and lubricates the joint, reduces friction, and provides nutrients to the cartilage.

Meniscus

A fibrocartilage pad found in knee joints (-i plural).

Bursa

Fluid-filled sacs found in some joints that help reduce friction (-ae plural).

Ball-and-Socket Joint

A synovial joint with a round head in a cup-shaped cavity; multiaxial and provides the widest range of motion (e.g., hip and shoulder).

Condylar Joint

A biaxial synovial joint allowing back-and-forth and side-to-side movement but no rotation (e.g., joints between metacarpals and phalanges).

Plane Joint

Also called a gliding joint, this synovial joint is almost flat or slightly curved; allows back-and-forth and twisting movements.

Hinge Joint

A synovial joint that allows uniaxial movement in $1$ plane (e.g., elbow or joints between phalanges).

Pivot Joint

A synovial joint limited to rotation only, such as the joint between the atlas ($C1$) and the dens of the axis ($C2$).

Saddle Joint

A biaxial synovial joint allowing movement in $2$ planes (e.g., between the carpal and metacarpal of the thumb).

Flexion

Bending of parts at a joint.

Extension

Straightening of parts at a joint.

Hyperextension

Extension of parts beyond the normal anatomical position.

Abduction

Moving a part of the body away from the midline.

Adduction

Moving a part of the body toward the midline.

Dorsiflexion

Ankle movement which points the toes upward toward the shin.

Plantar Flexion

Ankle movement which points the toes downward away from the shin.

Circumduction

Movement of a part of the body in a circular path.

Rotation

Moving a part of the body around an axis.

Supination

Forearm rotation so the palm faces upward or forward, or lying down face up.

Pronation

Forearm rotation so the palm faces downward or backward, or lying down face down.

Inversion

Turning of the foot so the plantar surface faces the midline.

Eversion

Turning of the foot so the plantar surface faces away from the midline.

Protraction

Movement of a bone in a joint forward.

Retraction

Movement of a bone in a joint backward.

Elevation

Raising a bone in a joint, such as the scapula.