Joints-lecture part 1

  1. Define articulation
    site where two or more bones meet
  2. Functions of joints
    • -Give skeleton mobility
    • -hold skeleton together (sometimes protective)
  3. How are joints functionally classified?
    Based on the amount of movement allowed by the joint
  4. What are the functional classification of joints

    Amphiarthroses--slightly movable

    Diarthroses--freely movable
  5. How are joints classified by structure?
    Based on the material binding bones together and whether or not a joint cavity is preent
  6. What are the structural classifications for joints?
    • 1. Fibrous
    • 2. Cartilaginous
    • 3. Synovial
  7. Fibrous Joints
    • -Most are synarthtrotic
    • -No joint cavity
    • - Bones are joined by a dense fibrous connective tissue
    • -amount of movement determined by the length of the connective tissue uniting the bones
    • -3 types:
    • Sutures
    • Syndesmoses
    • Gomphoses
  8. Fibrous Joints
    Only found in the skull

    • -rigid interlocking joints containing short connective tisue fibers
    • -allow for growth during youth
    • -In middle age, sutures ossify and are called synotoses
  9. Fibrous Joints
    -bones connected by ligaments (bands of fibrous tissue)

    -movement varies from immovable to slightly movable

    examples: synarthrotic distal tibiofibular joint, diarthrotic interosseous connection between radius and ulna
  10. Fibrous Joints
    -Peg in socken joints of teeth in alveolar sockets

    -fibrous connection is the periodontal ligament
  11. Carilaginous Joints
    • - joints untied by cartilage
    • -no joint cavity
    • -two types:
    • 1. synchondroses
    • 2. Symphyses
  12. Cartilaginous Joints
    • - a bar or plate of hylaine cartilage unites the bones
    • - all are synarthrotic

    examples: epiphyseal plate in long bones of children, joint between the first rib and sternum
  13. Cartilagious Joints:
    • - hyaline cartilage covers articulating surfaces and is fused to an intervening pad of fibrocartilage
    • -strong, flexible
    • -amphiarthroses

    examples: intervertebral discs and pubic symphesis
  14. Synovial Joints
    • -All are diarthrotic
    • -Include all limb joints; most joints of the body
  15. Synovial Joints
    Distinguising features
    • 1. Articular cartilage: hyaline cartilage
    • -covers opposing bone surfaces

    • 2. Joint (synovial) cavity: small potential space
    • -contains a small amount of synovial fluid

    • 3. Articular (joint) capsule: encloses joint cavity
    • -outer fibrous capsule of dense irregular connective tissue that's contiunous with the periosteua of articulating bones
    • -inner synovial membrane of loose connective tissue that covers all internal joint surfaces not covered with hyaline cartilage

    • 4. Synovial Fluid: occupies free space in joints
    • -viscous slippery fi;trate of plasma and hyaluronic acid
    • -lubricates and noursishes the articular cartilage
    • -reduces friction between cartilages

    • 5. 3 Different types of reinforcing ligaments
    • a. Capsular (instrinsic)- part of the fibrous caspsule
    • b. Exatrcapsular- outside the capsule
    • c. Intracapsular- deep to the capsule; covered by synovial membrane

    • 6. Rich nerve and blood vessel supply
    • -nerve fibers detect pain, monitor joint position and stretch
    • -capillary beds produce filtrate for synovial fluid
  16. Synovial Joints: friction-reducing structures
    • -flattened, fibrous sacs lined with synovial membranes
    • -contain synovial fluid
    • -commonly act as ball-bearins where ligaments, muscles, skin, tendons, or bones rub together
  17. Synovial Joints: friction-reducing structures
    Tendon Sheath
    • -enlongated bursae that wraps completely around a tendon
    • -common where seeveral tendons are crowded together in narrow canals, like in the wrist
  18. Difference between a ligament and a tendon
    ligaments: bone to bone

    tendons: bone to muscle
  19. Stablizing Factors of synovial joints
    • 1. Shapes of the articular surface
    • -minor role
    • -help to determine what kind of movement, but some shallow sockets don't really help at all

    • 2.Ligmanet number and location
    • -limited role
    • -prevents excessive and undesireable motion, however the joint is not very stable when ligaments are the major means. They only stretch to about 6% before they snap

    • 3. Muscle tone
    • -keeps tendons that cross joints taught
    • -extremely important in reinforcing shoulder and knee joints and arches of the foot
  20. Synovial Joints: Movement
    • Muscles attach acrosss a joint:
    • 1. origin-attachments to the immovable bone
    • 2. insertion- attachment to the movable bone

    • -muscle contraction cases the insertion to move toward the origin
    • -movements occur along transverse, frontal, or sagittal planes
  21. Synovial Joints: range of motion
    • 1. Nonaxial- slipping movements only
    • 2. Uniaxial- movement in one plane
    • 3. Biaxial- movement in two planes
    • 4. Multiaxial- movement in or around all 3 planes
  22. Movements of Synovial Joints
    • -simplest joint movement
    • -when one flat or nearly flat bone glides over another at no angle
    • exmaples: intercarpal joints, intertarsal joints, between articular processes of vertebrae
    • Image Upload 1
  23. Movements of Synovial Joints
    Angular Movements
    • movements occur along the sagittal plane:
    • Flexion- decreases angle
    • Extension- increases angle
    • Hyperextension- increases angle beyond anatomical position
    • Image Upload 2
    • movements that occur along the frontal plane:
    • Abduction- moving away from the medial body
    • Adduction- moving towards the medial body
    • Image Upload 3
    • Circumduction- cone shape movement
  24. Movements of Synovial Joints
    Lateral and Medial rotations

    • -the turning of a bone around its own long axis
    • example: c1 and c2 vertebrae, rotation of humerous and femur
  25. Movements of Synovial Joints
    Supination and Pronation
    Image Upload 4
  26. Movements of Synovial Joints
    Dorsiflextion and plantar flexion
    Image Upload 5
  27. Movements of Synovial Joints
    Inversion and eversion
    Image Upload 6
  28. Movements of Synovial Joints
    protraction and retraction
    -movements ina transverse plane
  29. Movements of Synovial Joints
    elevation and depression
    Image Upload 7
  30. Movements of Synovial Joints
    • movement in the saddle joint so that the thumb touches the tips of the other fingers
    • Image Upload 8
  31. Classification of Synovial Joints
    Based on the shape of the articular surface
  32. Classification of Synovial Joints
    Plane Joint
    • -non axial joint
    • -flat articular surfaces
    • -short gliding movements (gliding is the only example of a plane joint)
  33. Classification of Synovial Joints
    Hinge Joints
    • -Uniaxial joints
    • -motion along a simple plane
    • -flexion and extension only
    • Image Upload 9
  34. Classification of Synovial Joints
    Pivot joints
    • -Rounded one end of bone conforms to a "sleeve" or "ring" of another bone
    • -Uniaxial movement only
    • Example: C1 and C2 allow you to say no
    • Image Upload 10
  35. Classification of Synovial Joints
    Condyloid (Ellipsoidal) Joint
    • -Biaxial Joints
    • -Both articular surfaces are oval (one oval fits into the depression of another)
    • - Permit all angular movements
    • Image Upload 11
  36. Classification of Synovial Joints
    Saddle Joints
    • -Biaxial
    • -allow greater freedom of movement than condyloid joints
    • -Each articular surface has both concave and convex areas
    • Image Upload 12
  37. Classification of Synovial Joints
    Ball and Socket Joint
    • -Multiaxial joint
    • -the most freely moving synovial joints
    • Image Upload 13
Card Set
Joints-lecture part 1
joints chapter for a and p lecture part 1, types of joints