Lab 4 Review (Chapters 10 and 12)

3 Main Types of Joints

Fibrous: connective cartilage fibers between 2 bones → little movement

Cartilaginous: cartilage between 2 bones → generally more moveable, but some not at all

Synovial: joint capsule, inner membrane, and synovial fluid → most movable

Suture, Gomphosis, Syndesmosis

All Fibrous Joint Types

Suture: binds bones tightly together

Gomphosis: peg in a socket (like teeth)

Syndesmosis: long fibers connecting

What is Synostosis

When 2 bones completely fuse together

Types of Cartilaginous Joints

Synchondroses: can be movable or immovable depending on how long the cartilage is

Symphysis: cartilage pad that joins 2 bones (like intervertebral discs)

Synarthroses vs Amphiarthroses vs Diarthroses

Syn → no movement

Amphi → little movement

Di → free movement

Synovial Joint Capsule Parts

Fibrous Capsule: outer layer

Synovial Membrane: inner layer

Synovial Membrane

Excretes synovial fluid (friction reducing liquid) into the synovial cavity

Synovial Cavity

Where synovial fluid and the ends of bone wrapped in articular cartilage are housed

Nonaxial vs Uniaxial vs Biaxial vs Multiaxial

Also Joint Types for Each

Nonaxial: no movement on an axis, just sliding
- plane

Uniaxial: movement on 1 axis
- hinge
- pivot

Biaxial: movement on 2 axis
- condylar
- saddle

Multiaxial: free movement
- ball and socket (only shoulder and hip)

Adduction and Abduction

Adduction: towards the midline

Abduction: away from the midline

Flexion and Extension

Flexion: decreasing the joint angle from anatomical position

Extension: returning to anatomical position

Hyperextension: extending beyone anatomical position

Medial and Lateral Rotation

Medial: rotating towards midline

Lateral: rotating away from midline

Pronation and Supination

Pronation: thumb from lateral → medial

Supination: thumb from medial → lateral (anatomical position is supinated)

Inversion and Eversion

Inversion: turning ankle laterally (supination of the foot)

Eversion: turning ankle medially (pronation of the foot)