PDHPE - Synovial joints

Structure

• Articular Capsule

• Articular Cartilage

• Synovial fluid

• Bursa

Articular capsule

A capsule that encloses the joint cavity

Articular cartilage

A connective tissue covering the surface of articulating bones

Synovial fluid

a secretion that lubricates and nourishes the articular cartilage

Bursa

Small sac containing synovial fluid, located at friction sites between bones and tendons.

What connects the synovial joints?

• Ligaments

• Tendons

• Articular cartilage

Ligaments

Connects bones to bones

Tendons

connects muscles to bones

Articular cartilage - connecting joint

provides smooth, lubricated surface for articulating bones.

Types of synovial joints

• Pivot

• Hinge

• Saddle

• Gliding

• Condyloid

• Ball and socket

Pivot Joint function

Allows for rotation of one bone around another

Examples of pivot joint

atlas and axis

Hinge joint function

allows flexion and extension

Examples of hinge joint

elbow, knee

Saddle joint function

Allows for flexion, extension, adduction, abduction and circumduction

Examples of saddle joint

thumb joint

Plane/Gliding joint function

allows for gliding movements

Examples of gliding joint

joints between carpals, joints between tarsals.

Function of condyloid joint

Allows for flexion, extension, adduction, abduction and circumduction

Condyloid joint examples

joints between the radius and carpal bones of the wrist

Ball and socket joint function

Allows for flexion, extension, adduction, abduction, and internal and external rotation.

Ball and socket examples

Shoulder, hip

Joint actions

Flexion, extension, adduction, abduction, Dorsiflexion, plantar flexion, pronation, supination

Flexion

Decreasing angle at the joint

Extension

Increasing angle at the joint

Abduction

moving away from midline

Adduction

moving towards the midline

Dorsiflexion

the action of raising the foot upward toward the shin

Plantar flexion

the movement of the foot in a downward motion away from the body

Supination

when the hand rotates to being palm up

Pronation

when the hand rotates to being palm down