Joints = Articulations
- Where 2 bones come together
- Functions of joints
- Allow for mobility
- Ways joints are classified
- Functionally
- Structurally
Structural Classification of Joints
Special Movements - at specific joints:
Functional Classification of Joints
- Fibrous joints
- Generally immovable = Synarthroses
- Cartilaginous joints
- Immovable = Synarthroses
- Slightly movable = Amphiarthrosis
- Synovial joints
- Freely movable = Diarthroses
- Synarthroses – immovable joints
- Ex. Skull sutures, teeth
- Amphiarthroses – slightly moveable joints
- Ex. Between vertebrae, at disc
- Diarthroses – freely moveable joints
- Ex. knee, elbow, wrist
- Elevation/depression: Pectoral Girdle
- Eversion/inversion: Ankle/ Tarsals
- Dorsiflexion/plantar flexion: Metatarsals
- Opposition of thumb: Mecarpals
- Supination/pronation: Ankle/ Tarsals
- Protraction/retraction: Pectoral Girdle
Synovial Joints
Types of Movement
Structures Associated with Synovial Joints
- Articulating bones are separated by a joint cavity
- Synovial fluid is found in the joint cavity
- Features Associated with Synovial Joints
- Articular cartilage (hyaline cartilage) covers the ends of bones
- Joint surfaces are enclosed by a fibrous articular capsule
- Have a joint cavity filled with synovial fluid
- Ligaments reinforce the joint
Fibrous and Cartilaginous Joints
- Bursae – flattened fibrous sacs
- Lined with synovial membranes
- Filled with synovial fluid
- Not actually part of the joint
- Tendon sheath
- Elongated bursa that wraps around a tendon
- Flexion: bending
- Extension: straightening
- Abduction: movement away from midline
- Adduction: movement toward the midline
- Pronation: rotation of the forearm with palms down
- Supination: rotation of the forearm with palms up (anatomical position)
- Rotation: movement of a structure about the long axis
- Fibrous Joints
- Bones united by fibrous CT
- Sutures
- Cartilaginous Joints
- Bones connected by cartilage
- Pubic symphysis
- Intervertebral joint
Types of Joints