Lecture Notes on Joint Classifications and Movements

Introduction

• Discussion of free movements and structural joints.
• Emphasis on understanding joint classification and movement for specific questions.
• Use of color coding (red, green, yellow) to enhance learning through visual associations.

Types of Joints

Structural Joints

• Fibrous Joints: Held together by fibers, no synovial cavity.

  • May be synarthritic (immovable) depending on age and location.
  • Types:
    • Sutures: Found in the skull.
    • Syndesmosis: Found between tibia and fibula; includes gomphoses (teeth).
    • Interosseous Membrane: Found between paired bones like tibia and fibula.

• Cartilaginous Joints: Held together by cartilage, no synovial cavity.

  • Types:
    • Synchondrosis: Held by hyaline cartilage, found in epiphyseal plates, first rib.
    • Symphysis: Held by fibrocartilage, found in intervertebral discs, pubic symphysis.

• Synovial Joints: Have synovial cavity, diarthrosis (freely movable).

  • Characteristics:
    • Articular cartilage (hyaline).
    • Synovial cavity: Joint capsule with fibrous and synovial layers.
    • Synovial fluid: Lubricates joints, provides nutrients.

Accessory Structures of Synovial Joints

• Menisci: Fibrocartilage discs, absorb shock, present in knee, TMJ.
• Bursa: Fluid-filled sacs, reduce friction, located outside synovial joints.
• Tendon Sheaths: Elongated bursa, wrap around tendons to reduce friction.

Joint Movements

• Movement types depend on joint shape.
• Synovial Joint Types:
  • Ball and socket (shoulder, hip).
  • Examples of movements: flexion, extension, rotation.

Major Synovial Joints

• Glenohumeral Joint (Shoulder):

  • Most freely movable, most unstable.
  • Ball and socket, prone to dislocation.

• Coxal Joint (Hip):

  • Ball and socket, more stable due to deeper socket and stronger ligaments.
  • Allows similar movements to the shoulder.

• Tibiofemoral Joint (Knee):

  • Largest and most complex, three joints in one cavity.
  • Modified hinge joint, allows flexion, extension, and slight rotation.

Examination and Review

• Importance of vocabulary, structure, and definition comprehension.
• Use of quizzes and tests to reinforce learning.
• Suggestion to practice and review materials thoroughly before exams.