Arthrology: Study of Joints

Arthrology: Study of Joints

• Joint: Point of contact between two bones

• Joint Classification (Structurally): Categorized based on anatomical characteristics

  • Fibrous Joints: Lack cartilage, held together by fibrous tissue
    • Sutures: Immovable (found in skull)
    • Syndesmoses: Slightly movable (e.g., distal tibiofibular joint)
    • Gomphoses: Immovable (e.g., tooth in jaw socket)
  • Cartilaginous Joints: Connected by cartilage
    • Synchondroses: Immovable (e.g., epiphyseal plates)
    • Symphyses: Slightly movable (e.g., pubic symphysis, intervertebral discs)
  • Synovial Joints: Freely movable, contain synovial fluid
    • Specific types of synovial joints exist with different movement types (discussed further)

• Joint Classification (Functionally): Categorized by degree of movement

  • Synarthroses: Immovable
  • Amphiarthroses: Slightly movable
  • Diarthroses: Freely movable

Types of Synovial Joints

• Plane Joint: Flat surfaces, biaxial (e.g., intercarpal, intertarsal joints)
• Hinge Joint: Convex surface fits into concave surface, uniaxial (e.g., elbow, knee, interphalangeal joints)
• Pivot Joint: Projection of bone fits into notch, uniaxial (e.g., atlanto-axial, proximal/distal radioulnar joints)
• Condyloid Joint: Oval projection fits into oval depression, biaxial (e.g., wrist, metacarpophalangeal joints)
• Saddle Joint: Saddle-shaped surfaces, biaxial (e.g., carpometacarpal joint of thumb)
• Ball-and-Socket Joint: Ball-like end fits into cup, triaxial (e.g., hip, shoulder joints)

Joint Movements

• Angular Movements: Increase or decrease in the angle between bones
  • Flexion: Decreases the angle
  • Extension: Increases the angle
  • Hyperextension: Extension beyond normal range.
  • Abduction: Movement away from midline
  • Adduction: Movement towards midline
• Circumduction: Circular movement of a limb
• Rotation: Bone revolves around its longitudinal axis
• Special Movements: Specific to certain joints (e.g., inversion, eversion, protraction, retraction)
• Gliding: Flat bone surfaces move back and forth
• Supination/Pronation: Movement of the forearm rotating the palm
• Dorsiflexion/Plantar Flexion: Flexion and extension movements of the foot
• Protraction/Retraction: Anterior-Posterior movement of a body part

Explore the fascinating world of joints in the study of arthrology. This quiz covers joint classifications including fibrous, cartilaginous, and synovial types, as well as their structural and functional characteristics. Test your knowledge on how these joints connect bones and facilitate movement.