Chapter 8 Joints FC

Joints: Overview

• Articulation: Site where two or more bones meet.

• Functions of Joints:

  • Provide skeleton mobility.

  • Hold skeleton together.

Functional Classification of Joints

• Classifications Based on Movement:

  • Synarthroses: Immovable joints.

  • Amphiarthroses: Slightly movable joints.

  • Diarthroses: Freely movable joints.

Structural Classification of Joints

• Based on Material Binding Bones Together:

  • Fibrous Joints: No joint cavity, connected by dense connective tissue.

  • Cartilaginous Joints: Bones united by cartilage, no joint cavity present.

  • Synovial Joints: Have a joint cavity and are diarthrotic (freely movable).

Fibrous Joints

• Characteristics:

  • Bones joined by dense fibrous connective tissue without a joint cavity.

  • Most are synarthrotic (immovable).

• Types of Fibrous Joints:

  • Sutures: Rigid, interlocking joints with short connective tissue fibers, allowing for growth during youth.

  • Syndesmoses: Bones connected by ligaments; movement can be limited to slightly movable.

    • Example: Synarthrotic distal tibiofibular joint, diarthrotic interosseous connection between radius and ulna.

  • Gomphoses: Peg-in-socket joints, as in teeth in alveolar sockets; fibrous connection is the periodontal ligament.

Cartilaginous Joints

• Characteristics:

  • Bones united by cartilage without a joint cavity.

• Types of Cartilaginous Joints:

  • Synchondroses: Hyaline cartilage unites bones, all are synarthrotic; example includes the connection between the first rib and sternum.

  • Symphyses: Hyaline cartilage covers articulating surfaces with fibrous cartilage in between; strong, slightly movable (amphiarthroses).

    • Example: Intervertebral discs, pubic symphysis.

Synovial Joints

• Characteristics:

  • All are diarthrotic (freely movable).

  • Include all limb joints and most joints in the body.

• Distinguishing Features:

  • Articular Cartilage: Hyaline cartilage covering bone surfaces.

  • Joint (Synovial) Cavity: Small