ch6 & ch8

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ch6 & ch8
2014-01-31 16:29:10
bones and joints exam
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  1. skeletal cartilage
    • -water lends resiliency
    • -contains no blood vessels or nerves
    • -perichondrium surrounds : provides a dense connective tissue girdle
    •       -has nerves and blood vessels for
    •        nutrient delivery
    •       -resists outward expansion
  2. what do all the skeletal cartilages contain
    chondrocytes in lacunae and extracellular matrix
  3. what are the types of skeletal cartilages
    hyaline, elastic and fibro
  4. hyaline cartilage
    provides support and resiliency; collagen fibers only; most abundant type;

    articular, costal, respiratory, and nasal cartilage
  5. elastic cartilage
    similar to hyaline cartilage, but contains elastic fibers; 

    external ear and epiglottis
  6. fibrocartilage
    thick collage fibers, and has tensile strength

    menisci of the knee and vertebral discs
  7. what are the types of growth for cartilage
    appositional growth and interstitial growth and cartilage calcification
  8. appositional growth
    Cells secrete matrix against external face of existing cartilage
  9. interstitial growth
    Chondrocytes divide and secrete new matrix, expanding cartilage from within
  10. calcification of cartilage
    happens in both young and old people. occurs during normal bone growth; hardens but is not bone (i.e. fontanelle)
  11. what is the spot on the baby's head for cartilage forms to bone
    the fontanelle
  12. how are the 206 bones in the skeleton divided
    into axial and appendicular
  13. axial skeleton
    long axis of the body; skull, vertebral column, and rib cage
  14. appendicular skeleton
    bones of upper and lower limbs, girdles attaching limbs to axial skeleton; 

    pelvic and pectoral girdles attaching them
  15. what are the shapes that we classify bones by
    • long bones (femur)
    • short bones (metatarsals)
    • irregular bones (vertebral bones)
    • flat bone (skull)
  16. long bones
    • longer than they are wide
    • limb, wrist, and ankle bones
  17. short bones
    • cube-shaped bones (wrist and ankles)
    • sesamoid bones (patella)
    • vary in size and number in different individuals
  18. flat bones
    • thin, flat, and slightly curved
    • sternum, scapulae, most skull bones, ribs
  19. irregular bones
    • complicated shapes
    • vertebrae and coxal bones
  20. what are the seven important functions of bone
    • –Support: for body and soft organs
    • –Protection: for brain, spinal cord, vital organs
    • –Movement: levers for muscle action
    • –Mineral and growth factor storage:calcium and phosphorous reservoir
    • –Blood cell formation: hematopoeisis in red marrow cavities of certain bones
    • –Triglyceride (fat) storage: energy source
    • –Hormone production: osteocalcin
  21. what is osteocalcin
    bone hormone; regulates bone formation and protects against obesity, diabetes, glucose intolerance, etc.
  22. are bones organs
    • yes! they contain different tissue types:
    • osseous tissue
    • nervous tissue
    • muscle tissue
    • cartilage tissue
    • epithelial cells in blood vessels
  23. what are the three levels of structure of bone
    • gross anatomy
    • microscopic
    • chemical
  24. Gross Anatomy of bone
    • Bones Textures: compact and spongy bone
    • Compact: dense outer layer; smooth & solid
    • Spongy (cancellous or trabecular): Honeycomb of flat pieces of bone deep to compact called trabeculae
  25. structure of short, irregular, and flat bones
    • -Thin plates of spongy bone surrounded by compact bone
    • -Plates sandwiched between connective tissue membranes (periosteum and endosteum)
    • -No shaft or epiphyses
    • -Bone marrow throughout spongy bone; no marrow cavity
    • -Hyaline cartilage covers articular surfaces
  26. what is diploe
    another word for spongy bone tissue lining the short, irregular, and flat bones
  27. structure of typical long bone
    • Diaphysis:
    • -tubular shafts forms long axis;
    • -compact bone surrounding medullary cavity

    • Epiphyses:
    • -bone ends
    • -external compact bone internal spongy bone;
    • -articular cartilage covers articular surfaces;
    • -between is epiphyseal line
  28. epiphyseal line
    remnant of childhood bone growth at epiphyseal plate; if it is a line, the bone is from an adult, if it is cartilage, it is from a child
  29. the color of bone marrow in adults vs. children
    adults have yellow bone marrow and children have red bone marrow; adults bone marrow can change back to red through trauma, but mostly yellow
  30. what is a tell tale sign that you are looking at the head of a bone
    the presence of articular cartilage
  31. membranes: periosteum
    • -White double-layered membrane
    • -Covers external surfaces except joint surfaces
    • -Outer fibrous layer of dense irregular connective tissue
    •        -Sharpey's fibers secure to bone matrix
    • -Osteogenic layer abuts bone
    •        -contains primitive stem cells --
    •         osteogenic cells
    • -Many nerve fibers and and blood vessels
    • -Anchoring point for ligaments and tendons
  32. what is the articular cartilage made of
    hyaline cartilage
  33. membranes: endosteum
    • -Delicate connective tissue membrane covering internal bone surface
    • -Covers trabeculae of spongy bone
    • -Lines canals that pass through spongy bone
    • -Contains osteogenic cells that can differentiate into other cells
  34. Osteogenic cells produce what cells
    produce more cells; osteocytes, osteoclasts, osteoblasts
  35. osteoblast vs osteoclast vs osteocyte
    • osteoblast: builds bone
    • osteoclast: breaks down bone
    • osteocyte: bone cell
  36. hematopoietic tissue in bones: red marrow
    • -Found within trabecular cavities of long bones and diploe of flat bones (sternum)
    • -In medullary cavities and spongy bone of newborns
    • -Adult long bones have little red marrow
    •     -In the heads of the femur and humerus
    •       only
    • -Red marrow in diploe and some irregular bones is most active
    • -Yellow marrow can convert to red if necessary
  37. What are the types of bone markings
    • Sites of muscle, ligament, and tendon attachment on external surfaces
    • Joint surfaces
    • Conduits for blood vessels and nerves
    • Projections
    • Depressions
    • Openings
  38. Bone markings: Projection
    • Most indicate stresses created by muscle pull or joint modifications:
    •     -depressions and openings
    •     -usually allow nerves and blood vessels to
    •      pass
  39. tuberosity
    large rounded projection; may be roughened  (projection that are sites of ligament and muscle attachment)
  40. crest
    Narrow ridge of bone; usually prominent  (projection that are sites of ligament and muscle attachment)
  41. trochanter
    Very large, blunt, irregulary shaped process (the only examples are on the femur)  (projection that are sites of ligament and muscle attachment)
  42. line
    Narrow ridge of bone; less prominent than a crest  (projection that are sites of ligament and muscle attachment)
  43. tubercle
    Small rounded projection or process  (projection that are sites of ligament and muscle attachment)
  44. Epicondyle
    Raised area on or above a condyle  (projection that are sites of ligament and muscle attachment)
  45. Spine
    Sharp, slender, often pointed projection  (projection that are sites of ligament and muscle attachment)
  46. Process
    Any bony prominence (projection that are sites of ligament and muscle attachment)
  47. Head
    Bondy expansion carried on a narrow neck (projection that helps form joints)
  48. Facet
    Smooth, nearly flat articular surface (projection that helps form joints)
  49. condyle
    Rounded articualr projection (projection that helps form joints)
  50. ramus
    Armlike bar of bone (projection that helps form joints)
  51. Groove
    Furrow (for passage of blood vessels and nerves)
  52. Fissure
    Narrow, slit-like opening (for passage of blood vessels and nerves)
  53. Foramen
    Round or oval opening through a bone (for passage of blood vessels and nerves)
  54. Notch
    Indentation at the edge of a structure (for passage of blood vessels and nerves)
  55. Meatus
    Canal-like passageway (for passage of blood vessels and nerves)
  56. Sinus
    Cavity within a bone, filled with air and lined with mucous membrane (other)
  57. Fossa
    Shallow, basinlike depression in a bone, often serving as an articular surface (other)
  58. what are the five major cell types of bone tissue
    • osteogenic cells
    • osteoclast
    • osteoblast
    • osteocyte
    • bone lining cells

    (each are a specialized form of same basic cell type)
  59. osteogenic cells
    • Also called osteoprogenitor cells
    • Mitotically active stem cells in periosteum and endosteum
    • When stimulated differentiate into osteoblasts or bone lining cells
    •      -some persist as osteogenic cells
  60. osteoprogenitor cells
    another word for osteogenic cells
  61. osteoblast
    • Bone-forming cells
    • Secrete unmineralized bone matrix or osteoid
    •     -includes collagen and calcium-binding
    •      proteins (collagen=90% of bone protein)
    • Actively mitotic
  62. osteocyte
    • Mature bone cells in lacunae
    • Monitor and maintain bone matrix
    • Act as stress or strain sensors
    •    -Respond to and communicate mechanical
    •      stimuli to osteoblasts and osteoclasts so
    •      bone remodeling can occur
  63. Bone Lining Cells
    • Flat cells on bone surfaces believed to help maintain matrix
    • On external bone surface called periosteal cells
    • Lining internal surfaces called endosteal cells
  64. Osteoclasts
    • Derived from hematopoietic stem cells that become macrophages
    • Giant, multinucleate cells for bone resportion
    • When active rest in resorption bay and have ruffled border
    •      -ruffled border increases surface area for enzyme degradation of bone and seals off area from surround matrix
  65. Microscopic Anatomy of bone: compact bone
    • -Also called lamellar bone
    • -Osteon or haversian system
    •    -Structural unit of compact bone
    •    -Elongated cylinder parallel to long axis of
    •      bone
    •    -hollow tubes of bone matrix called lamellae
    •             -Collagen fibers in adjacent rings run
    •               in different directions to withstand
    •               stress and resist twisting

    • \ first ring
    • ///// second ring
    • \ third ring

    • -Canals and canaliculi
    •      -central (haversian) canal runs through
    •       core of osteon
    •               -contains blood vessels and nerve
    •                 fibers
    • -Perforating (volkmann's) canals
    •      -canals lined with endosteum at right angles
    •        to central canal
    •      -connect blood vessels and nerves of
    •        periosteum, medullary cavity, and central
    •         canal
    • -Lacunae: small cavities that contain osteocytes
    • -Canaliculi: hairlike canals that connect lacunae to each other and central canal
  66. Canaliculi formation
    • Osteoblasts secreting bone matrix maintain contact with each other and osteocytes via cell projections with gap junctions
    • When matrix hardens and cells are trapped the canaliculi form
    •      -allow communication
    •      -permit nutrients and wastes to be relayed
    •        from one osteocyte to another throughout
    •       osteon
  67. Lamellae
    • Interstitial lamellae
    •    -incomplete lamellae not part of complete
    •      osteon
    •    -fill gaps between forming osteons
    •    -remnants of osteons cut by bone remodeling

    • Circumferential lamellae
    •    -just deep to periosteum
    •    -superficial to endosteum
    •    -extend around entire surface of diaphysis
    •    -resist twisting of long bone
    •    -not part of the Haversian system they
    •     surround and separate
  68. Microscopic Anatomy of Bone: Spongy Bone
    • Appears poorly organized
    • Trabeculae
    •    -Align along lines of stress to help resist it
    •    -No osteons
    •    -Contain irregularly arranged lamellae and
    •      osteocytes interconnected by canaliculi
    •    -Capillaries in endosteum supply nutrients
  69. Chemical Composition of Bone: Organic Components
    • -Includes cells and osteoid
    •    -osteogenic cells, osteoblasts, osteocytes,
    •      bone-lining cells, and osteoclasts
    •    -Osteoid: is 1/3 organic bone matrix
    •                   secreted by osteoblasts
    •            *Made of ground substance
    •              (proteoglycans and glycoproteins)
    •            *Collagen fibers
    •            *Contributes to structure; provides
    •              tensile strength and flexibility

    • -Resilience of bone due to sacrificial bonds in
    •    or between collagen molecules
    •     -stretch and break easily on impact to
    •       dissipate energy and prevent fracture
    •     -if not addition trauma, bonds re-form
  70. Chemical Composition of Bone: Inorganic components
    • Hydroxyapatites (mineral salts)
    •    -65% of bone by mass
    •    -mainly of tiny calcium phosphate crystals in
    •      and around collagen fibers
    •    -responsible for hardness and resistance to  
    •      compressions
  71. Describe the strength of bone
    • Half as strong as steel in resisting
    • As strong as steel in resisting tension
    • Last long after death because of mineral composition
    •     -reveals information about ancient people
    •     - can display growth arrest lines
    •             -horizontal lines on bones
    •             - proof of illness -when bones stop
    •               growing so nutrients can help fight
    •               disease
  72. Ossification
    • (Osteogenesis)
    • Process of bone tissue formation
    • Formation of bony skeleton
    •    -begins in 2nd month of development
    • Postnatal bone growth
    •    -under early adulthood
    • Bone remodeling and repair
    •    -lifelong
  73. What are the two types of ossification
    endochondral ossification and intramembranous ossification
  74. Endochondral Ossification
    • Bone forms by replacing hyaline cartilage
    • Requires breakdown of hyaline cartilage prior to ossification
    • Bones called cartilage (endochondral) bones
    • Forms most of skeleton inferior to skull (except
    •    clavicles)
  75. Intramembranous Ossification
    • Bone develops from fibrous membrane
    • Bones called membrane bones
    • Forms flat bones e.g. clavicles and cranial bones
  76. Endochondral Ossification Process
    • Begins at primary ossification center in center of shaft
    •    -blood vessel infiltration of perichondrium
    •     converts it to periosteum --> underlying cells
    •     change to osteoblasts
    • Bone collar forms around diaphysis of cartilage model
    • Central cartilage in diaphysis calcifies, then develops cavities
    • Periosteal bud invades cavities --> formation of spongy bone
    • Diaphysis elongates and medullary cavity forms
    • Epiphyses ossify
  77. Intramembranous Ossification
    • Forms frontal, partietal, occipital, temporal bones, and clavicles
    • Begins with fibrous connective tissue membranes formed by mesenchymal cells
    • Ossification centers appear
    • Osteoid is secreted
    • Woven bone and periosteum form
    • Lamellar bone replaces woven bone and red marrow appears
  78. Postnatal Bone Growth
    • Interstitial (longitudinal) Growth
    •   -increase in length of long bones
    • Appositional Growth
    •   -increase in bone thickness
  79. Interstitial Growth
    • Requires presence of epiphyseal cartilage
    • Epiphyseal plate maintains constant thickness
    •    -rate of cartilage growth on one side
    •     balanced by bone replacement on other
    • Concurrent remodeling of epiphyseal ends to maintain proportion
    • Result of five zones within cartilage
  80. what are the five zones within cartilage
    • Resting (quiescent) zone
    • Proliferation (growth) zone
    • Hypertrophic zone
    • Calcification zone
    • Ossification (osteogenic) zone
  81. Growth in Long Bones: Resting (quiescent) Zone:
    • Cartilage on epiphyseal side of epiphyseal plate
    • Relatively inactive
  82. Growth in Long Bones: Proliferation (growth) zone
    • Cartilage on diaphysis side of epiphyseal plate
    • Rapidly divide pushing epiphysis away from diaphysis (lengthening)
  83. Growth in Long Bones:: Hypertrophic zone
    Older chondrocytes closer to diaphysis and their lacunae enlarge and erode --> interconnecting spaces
  84. Growth in Long Bones: Calcification zone
    Surrounding cartilage matrix calcifies, chondrocytes die and deteriorate
  85. Growth in Long Bones: Ossification zone
    • Chondrocyte deterioration leaves long spicules of calcified cartilage at epiphysis-diaphysis junction
    • Spicules eroded by osteoclasts
    • Covered with new bone by osteoblasts
    • Ultimately replaced with spongy bone
  86. Epiphyseal Plate Closure
    • Bone lengthening ceases
    •   -requires presence of cartilage
    • Bone of epiphysis and diaphysis fuses
    • Females -18 years Males-21 years

    *When epiphyseal plate is done growing, it becomes epiphyseal line*
  87. Appositional Growth
    • Allows lengthening bone to widen
    • Occurs throughout life
    • Osteoblasts beneath periosteum secrete bone matrix on external bone
    • Osteoclasts remove bone on endosteal surface
    • Usually more building up than breaking down
    •   -thicker, stronger bone but not too heavy
  88. Hormones that regulate bone growth
    Growth hormone, thyroid hormone and testosterone (males) and estrogen (females)

    *excesses or deficits of any cause abnormal skeletal growth*
  89. Growth Hormone
    Most important in stimulating epiphyseal plate activity in infancy and childhood
  90. Thyroid hormone
    • Moderates activity of growth hormone
    • Ensures proper proportions
  91. Testosterone & Estrogen
    • Promote adolescent growth spurts
    • End growth by inducing epiphyseal plate closure
  92. Bone homeostasis
    • Recycle 5-7% of bone mass each week
    •    -spongy bone replaced every 3-4 years
    •    -compact bone replaced every 10 years
    • Older bone becomes more brittle
    •    -calcium salts crystallize
    •    -fractures more easily
    • Consists of bone remodeling and bone repair
  93. Bone Remodeling
    • Consists of bone deposit and bone resorption
    • Occurs at surfaces of both periosteum and endosteum
    • Remodeling units
    •     -adjacent osteoblasts and osteoclasts
  94. Bone Deposit
    • Evidence of new matrix deposit by osteoblasts
    •   -osteoid seam: unmineralized band of bone
    •     matrix
    •   -calcification front: abrupt transition zone
    •     between osteoid seam and older mineralized
    •     bone
    • Trigger not confirmed
    •   -mechanical signals involved
    •   -matrix proteins bind and concentrate calcium
    •   -enzyme alkaline phosphatase for
    •     mineralization
  95. Bone Resorption
    • Is function of osteoclasts
    •    -dig depressions or grooves as break down
    •     matrix
    •    -secrete lysosomal enzymes that digest
    •     matrix and protons (H+)
    •    -acidity converts calcium salts to soluble
    •     forms
    • Osteoclasts also phagocytize demineralized matrix and dead osteocytes.  Once resorption is complete, osteoclasts undergo apoptosis
    • Osteoclast activation involves PTH and T cell-secreted proteins
  96. What is PTH
    parathyroid hormone
  97. what is apoptosis
    controlled cell suicide
  98. Control of Remodeling
    • Occurs continuously but regulated by genetic factors and two control loops
    •    -Negative feedback hormonal loop for Ca2+
    •     homeostasis
    •            -controls blood Ca2+ levels; not bone
    •             integrity
    •    -Responses to mechanical and gravitational
    •     forces
  99. Main functions for which calcium is important
    • Nerve impulse transmission
    • Muscle Contraction
    • Blood coagulation
    • Secretion by glands and nerve cells
    • Cell division
  100. Calcium in the Body
    • 1200-1400 grams
    • 99% as bone minerals
    • Amount in blood in tightly regulated
    • Intestinal resorption requires Vitamin D metabolites
    • Dietary intake required
  101. Hormonal Control of Ca2+
    PTH: produced by parathyroid glands and removes calcium form bone regardless of bone integrity

    Calcitonin may be involved: produced by parafollicular cells of thyroid gland and in high doses lowers blood calcium levels temporarily
  102. Hypercalcemia
    • Sustained high blood calcium levels
    • Deposits of calcium salts in blood vessels, kidneys can interfere with function
  103. Reponse to Mechanical stress
    -Bones reflect stresses they encounter (long bonds are thickest midway along diaphysis where bending stresses greatest)

    -Bones stressed when weight bears on them or muscles pull on them (bending compresses on one side and stretches on other)
  104. Wolff's Law
    Bones grow or remodel in response to demands placed on it

    • -Handedness (right or left handed) results in
    •    thicker and stronger bone of that upper limb
    • -Curved bones thickest where most likely to
    •    buckle
    • -Trabeculae form trusses along lines of stress
    • -Large, bony projections occur where heavy,
    •    active muscles attach
    • -Bones of fetus and bedridden featureless
  105. How does mechanical stress cause remodeling
    Electrical signals produced by deforming bone may cause remodeling
  106. Hormonal vs Mechanical Influences
    Hormonal controls determine whether and when remodeling occurs to changing blood calcium levels

    Mechanical stress determines where remodeling occurs
  107. Leading cause of fractures in youth and adults
    • Youth: mostly from trauma
    • Adult: mostly from weakness from bone thinning
  108. What are the three either/or fracture classifications
    • 1) Position of bone ends after fracture
    • Nondisplaced: ends retain normal position
    • Displaced: ends out of normal alignment

    • 2) Completeness of break
    • Complete: broken all the way through
    • Incomplete: not broken all the way through

    • 3) Whether skin is penetrated
    • Open (compound): skin is penetrated
    • Closed (simple): skin is not penetrated

    *Also described by location of fracture, external appearance, and nature of break*
  109. Fracture Treatment
    Reduction: realignment of bone ends, closed reduction (physician manipulates to correct position), open reduction (surgical pins or wires secure ends)

    Immobilization: by cast or traction for healing (depends on break severity, bone broken, and age of patient)
  110. Stages of Bone Repair
    • 1) Hematoma forms: torn blood vessels hemorrhage, clot forms, swells and is painful
    • 2) Fibrocartilaginous Callus forms: capillaries grow into hematoma, phagocytic cells clear debris, fibroclasts secrete collagen fibers to span break and connect broken ends, fibroclasts, cartilage, and osteogenic cells begin reconstruction of bone (osteoblasts form spongy bone within matrix), mass of repair tissue called fibrocartilaginous callus
    • 3) Bony Callus forms: within one week new trabeculae appear in fibrocartilaginous callus, callus converted to bony callus of spongy bone, 2 months later firm union forms
    • 4) Bone modeling occurs: beings during body callus formation, continues for several months, excess material on diaphysis exterior and within medullary cavity removed, compact bone laid down to reconstruct shaft walls, final structure resembles original because they respond to the same mechanical stressors
  111. Osteoporosis
    • Group of diseases
    • Bone resorption outpaces deposit
    • Spongy bone of spine and neck of femur most susceptible (vertebral and hip fractures common)

    • Most common in aged postmenopausal women
    • Men to a lesser degree

    • Additional risks:
    • Petite body form
    • Insufficient exercise to stress bones
    • Poor diet in calcium and protein
    • Smoking
    • Immobility
    • Hormone-related conditions

    • Treatment:
    • Calcium, Vitamin D supplements, weight-bearing exercise, hormone replacement therapy
  112. Joints and its functions
    Articulation: site where two or more bones meet

    Gives skeleton mobility & holds skeleton together
  113. what are the two classifications of joints
    Functional & Structural
  114. How are functional joints determined and what are the three classifications
    Based on the amount of movement the joint allows

    • Synarthroses: immovable joints
    • Amphiarthroses: slightly moveable joints
    • Diarthroses: freely moveable joints
  115. How are the structural joints determined and what are the three classifications
    Based on the material binding bones together and the presence/absence of joint cavity

    • Fibrous joints
    • Cartilaginous joint
    • Synovial joints
  116. Fibrous joints
    • Bones joined by dense fibrous connective tissue
    • No joint cavity
    • Most synarthrotic (depends on length of connective tissue fibers)
    • Three types: Sutures, syndesmoses, gomphoses
  117. Sutures
    • Fibrous joint
    • Rigid, interlocking joints
    • Immovable joints for protection of brain
    • Contain short connective tissue fibers
    • Allow for growth during youth
    • In middle age, sutures ossify and fuse called Synostoses
  118. Synostoses
    Occurs during middle age when sutures ossify
  119. Syndesmoses
    • Fibrous joint
    • Bones connected by ligaments
    • Fiber length varies so movement varies
    •    -little to no movement at distal tibiofibular    
    •     joint
    •    -large amount of movement at interosseous
    •     membrane connecting radius and ulna
  120. Gomphoses
    • Fibrous joint
    • Peg-in-socket joints of teeth in alveolar sockets
    • Fibrous connection is the periodontal ligament
  121. Cartilaginous joints
    • Bones united by cartilage
    • No joint cavity
    • Not highly movable
    • Two types: Synchondroses and Symphyses
  122. Synchondroses
    • Cartilaginous joint
    • Bar/plate of hyaline cartilage unites bones
    •      e.g. temporary epiphyseal plate joints
    • All are synarthrotic
  123. Symphyses
    • Cartilaginous joint
    • Fibrocartilage unites bone 
    •    -hyaline still present as articular cartilage
    • Strong, flexible amphiarthoses 
  124. Synovial joints
    • Bones separated by fluid-filled joint cavity
    • All are diarthrotic
    • include all limb joints, most joints of the body
  125. What are the six distinguishing features of synovial joints
    • 1) Articular cartilage: hyaline cartilage; prevents crushing of bone ends
    • 2) Joint (synovial) cavity: small, fluid-filled potential space
    • 3) Articular (joint) capsule: has two layers; external fibrous layer (dense irregular connective tissue) internal synovial membrane (loose connective tissue and makes synovial fluid)
    • 4) Synovial fluid: viscous slippery filtrate of plasma and hyaluronic acid, lubricates and nourish articular cartilage, contains phagocytic cells to remove microbes and debris
    • 5) Different types of reinforcing ligaments: Capsular: thickened part of fibrous layer Extracapsular: outside the capsule Intracapsular: deep to capsule covered by synovial membrane
    • 6) Nerves and Blood vessels: nerve fibers detect pain, monitor joint position and stretch, capillary beds supply filtrate for synovial fluid
  126. Name other features of some synovial joints
    Fatty pads: for cushioning between fibrous layer and synovial membrane or bone

    Articular discs (menisci): fibrocartilage separates articular surfaces to improve fit of bone ends, stabilize joint, and reduce wear and tear
  127. What are the structures associated with synovial joints
    Bursae: sacs lined with synovial membrane (contain synovial fluid); reduce friction where ligaments, muscles, skin, tendons, or bones rub together

    Tendon Sheaths: elongated bursa wrapped completely around tendon subjected to friction
  128. What are the three stabling factors of synovial joints
    • 1) Shapes of articular surfaces (minor role)
    • 2) Ligament number and location (limited role)
    • 3) Muscle tendons that cross joint (most important) muscle tone keeps tendons taut and is extremely important in reinforcing shoulder and knee joints and arches of the foot
  129. Where and to what are all muscles attached
    All muscles attach to bone or connective tissue at no fewer than two points
  130. Origin
    Attachment to immovable bone
  131. Insertion
    Attachment to movable bone
  132. What are the six types of synovial joints and how are they decided
    Based on shape of articular surfaces

    • 1.Plane: between carpals
    • 2.Hinge: humerus and ulna (elbow)
    • 3.Pivot: ulna and radius
    • 4.Condylar: between metacarpals and phalanges
    • 5.Saddle: thumb
    • 6.Ball and Socket: shoulder and hip joints
  133. where is red marrow located in adults
    in the heads of the femur and humerus ONLY!