Articulations Study Guide

Flashcards on Articulations based on lecture notes.

Articulation

A point where bones meet.

Arthrology

The study of joints.

Kinesiology

The mechanics of body movement.

Range of Motion (ROM)

The extent of movement a joint can achieve.

Synarthrosis

Immovable joint.

Amphiarthrosis

Slightly movable joint.

Diarthrosis

Freely movable joint.

Fibrous Joint

Joint held together by collagen fibers; lacks a synovial cavity.

Suture

Immovable joint in the skull connected by a thin layer of dense connective tissue.

Synostosis

Bony joint formed when sutures ossify.

Gomphosis

Peg-and-socket joint; example is tooth/socket.

Syndesmosis

Slightly movable joint connected by a ligament; example is tibia/fibula.

Cartilaginous Joint

Joint held together by cartilage; lacks a synovial cavity.

Synchondrosis

Immovable joint made of hyaline cartilage; example is the first rib and manubrium.

Symphysis

Slightly movable joint connected by fibrocartilage; examples are pubic symphysis and intervertebral discs.

Synovial Joint

Freely movable joint with a synovial cavity.

Fibrous Layer

Outer layer of the articular capsule, continuous with the periosteum of adjacent bones.

Synovial Membrane

Inner layer of the articular capsule, produces synovial fluid.

Synovial Cavity

Area within the articular capsule, filled with synovial fluid.

Synovial Fluid

Fluid that lubricates, nourishes, and provides shock absorption within a joint.

Articular Cartilage

Covers articulating bone surfaces in synovial joints.

Intrinsic (Capsular) Ligaments

Thickened areas of the joint capsule.

Extrinsic Ligaments

Ligaments outside and separate from the joint capsule.

Intracapsular Ligament

Ligament running through the capsule

Extracapsular ligament

Ligament that stays outside the capsule

Articular Menisci (Meniscus)

Structures between articulating bones that attach to the joint capsule and direct synovial fluid flow.

Bursae

Synovial fluid-filled sacs for cushioning in an articulation.

Tendon Sheath

Tube-like bursa that surrounds tendons moving through a synovial cavity.

Lever

The 'handle' that moves in a lever system.

Fulcrum

The fixed point a lever moves around.

First Class Lever

Fulcrum is between load and force

Second Class Lever

Fulcrum is at one end, load is in the middle

Third Class Lever

Fulcrum is at one end, load is at the other end

Gliding

Movement where surfaces slide or glide over each other.

Flexion

Decreases the angle of the joint.

Extension

Increases the angle of the joint.

Hyperextension

Extension beyond the anatomical position.

Abduction

Movement away from the midline.

Adduction

Movement toward the midline.

Circumduction

Circular movement combining flexion, extension, abduction, and adduction.

Rotation

Pivoting movement around a longitudinal axis.

lateral rotation (external)

Turning anterior surface laterally

medial rotation (internal)

Turning anterior surface medially

Dorsiflexion

Lifting the foot so that its superior surface approaches the shin.

Plantar Flexion

Depressing the foot (pointing the toes).

Inversion

Turning the sole of the foot medially.

Eversion

Turning the sole of the foot laterally.

Supination

Rotating the forearm laterally so that the palm faces anteriorly or superiorly.

Pronation

Rotating the forearm medially so that the palm faces posteriorly or inferiorly.

Radial Flexion

Lateral movement of the hand at the wrist.

Ulnar Flexion

Medial movement of the hand at the wrist.

Protraction

Moving the mandible anteriorly.

Retraction

Moving the mandible posteriorly.

Elevation

Lifting a body part superiorly.

Depression

Moving a body part inferiorly.

Planar (Gliding) Joint

Joint where articulating surfaces are flat or slightly curved, allowing gliding movements.

Hinge Joint

Joint allowing movement in one plane (flexion and extension).

Pivot Joint

Joint allowing uniaxial rotation.

Condyloid (Ellipsoidal) Joint

Joint with an oval convex surface fitting into a complementary concave surface.

Saddle Joint

Joint with both concave and convex articulating surfaces.

Ball and Socket Joint

Joint where a spherical head articulates with a cup-like socket; allows multiaxial movement.

Glenohumeral Joint

Shoulder joint between the scapula and humerus.

Acromioclavicular Joint

Shoulder joint between the scapula and clavicle.

Glenoid Labrum

Ring of fibrocartilage that deepens the glenoid cavity.

Humeroulnar Joint

Elbow joint between humerus and ulna.

Humeroradial Joint

Elbow joint between humerus and radius.

Radioulnar Joint

Elbow joint between radius and ulna.

Acetabulofemoral Joint

Hip joint between the acetabulum of the coxal bone and the femur.

Knee

Large joint in the body involving the femur, tibia, and patella.

Anulus Fibrosis

Outer portion of the intervertebral disc, made of fibrocartilage.

Nucleus Pulposis

Inner portion of the intervertebral disc, a soft gelatinous core.