Cartilaginous joints

Adjoining bones united by cartilage with no joint cavity. Joints are either synarthrotic or amphiarthrotic.

Examples: Intervertebral discs, Pubic symphysis (fibrocartilage)

Synovial joints

Most common type of joint in body; joints are freely movable. Remember, slick as snot

Several defining structural characteristics:

a. Joint cavity (filled with synovial fluid)

b. Articular cartilage (hyaline cartilage covering ends of bones forming joint)

c. Articular capsule (two layers enclosing joint cavity. Fibrous layer (dense irregular connective tissue) and inner layer (synovial membrane))

d. Synovial fluid (viscous fluid acting as lubricant)

e. Reinforcing ligaments

f. Nerves and blood vessels (sensory nerve fibers to detect pain and joint stretching, blood vessels supply synovial membrane)

g. Articular discs

h. Bursa and tendon sheath

Examples: Elbow joint, shoulder joint, hip joint, etc

Types of synovial joints: Plane

non-axial (gliding); between flat or slightly curved bones

examples: intertarsal, intercarpal joints

Types of synovial joints: Hinge

Uniaxial (flexion and extension); a rounded or cylindrical bone fits into a concave surface on the other bone

examples: elbow, interphalangeal joints, knee

Types of synovial joints: Pivot

Uniaxial (rotation); A rounded bone fits into a sleeve (a concave bone plus a ligament)

examples: proximal radioulnar, atlantoaxial joint

Types of synovial joints: Condylar

Biaxial (flexion, extension, adduction, abduction); An oval condyle fits into an oval depression on the other bone

examples: metacarpophalangeal (knuckle) and radiocarpal joints; metacarpal/carpal joints

Types of synovial joints: Saddle

Biaxial (flexion, extension, adduction, abduction); Articulating surfaces are saddle shaped; one surface is concave, the other is convex

examples: carpometacarpal joint of the thumb (this is mostly where this joint is)

Types of synovial joints: Ball-and-socket

Multiaxial (flexion, extension, abduction, adduction, rotation); the ball-shaped head of one bone fits into the cuplike depression of the other bone

examples: shoulder, hip joints

Origin

stationary, immovable, or less movable attachment of muscle to bone; anchor for part of body that moves

Insertion

More movable attachment site of muscle to bone; part of body that moves

Flexion

Movement (usually in sagittal plane) that decreases the angle of the joint and reduces the distance between two bones (example bending knee or elbow)

Extension

Movement that increases the angle of the joint and the distance between two bones or parts of body; opposite of flexion.

Abduction

Movement of a limb away from the midline of the body, along the frontal plan, or the fanning movement of fingers or toes when they are spread apart. REMEMBER: Children are abducted from their parents...they are taken away

Adduction

Movement of a limb towards the midline of the body or drawing the fingers or toes together; opposite of abduction.

Rotation

Movement of a bone around its longitudinal axis without lateral or medial displacement. Also describes movement of atlas around dens of axis.

Circumduction

A combination of flexion, extension, abduction, and adduction commonly observed in ball and socket joints like the shoulder. The limb as a whole outlines a cone.

Pronation

Movement of the palm of the hand from an anterior or upward-facing position to a posterior or downward facing position. The distal end of radius rotates over the ulna.

Supination

Movement of the palm from a posterior position to an anterior position. Radius and ulna are parallel.

Dorsiflexion

Movement of ankle joint that lifts foot so that its superior surface approaches the shin

Plantar flexion

Movement of ankle joint in which foot flexes downward as if standing on one's toes or pointing the toes

Inversion

Movement that turns sole of the foot medially

Eversion

Movement that turns sole of foot laterally

Ligamentum teres

ligament in hip running from the fovea capitis on the femur head to the acetabulum, also called ligament of the head of the femur

Ligaments of the knee

patellar, medial, lateral patellar (merged with articular capsule)

fibular and tibial collateral ligaments (prevent rotation during extension)

oblique popliteal and arcuate popliteal ligaments (reinforce knee)

posterior and anterior cruciate ligaments (intracapsular and prevent overflexion and hyperextension)

Glenohumeral joint

Shoulder joint