HTHS Mod 9

Card Set Information

HTHS Mod 9
2013-12-02 12:48:39
Skeletal system

Skeletal system
Show Answers:

  1. General functions of the skeletal system
    • support
    • protection
    • movement
    • mineral homeostasis
    • hematopoesis
    • fat (energy) storage
    • "Some Prick Moved My Horse Further South"
  2. how does skeletal system support
    structural framework, attachment for tendons and ligaments
  3. how does skeletal system protect
    protects internal organs
  4. What function does skeletal system play in mineral homeostasis
    keeps blood calcium and phosphate within normal limits by storing and releasing these minerals
  5. What function does skeletal system play in hematopoiesis?
    • Hemato = blood; -poiesis = creation
    • production of blood cells in red bone marrow
  6. How does skeletal system store energy
    triglycerides (fat) stored in yellow bone marrow
  7. What type of tissue is bone?
    connective tissue
  8. four types of bone cells
    • osteogenic cell
    • osteocyte
    • osteoblast
    • osteoclast
    • **Osteoblast and Osteoclast are regulated by hormones
  9. osteogenic cell
    • a bone stem cell
    • develops into an osteoblast
    • the precursor to all the other cell types
  10. Osteoblasts
    • dividing cells that make bone
    • responsible for laying down the organic and inorganic extracellular matrix of bone
    • follow behind osteoclasts, rebuilding bone
    • remember B in blasts: bone building blasts
  11. osteocytes
    • "bone cells"
    • maintain bone tissue
  12. Osteoclasts
    • constantly tunnel through bone, using acid to dissolve mineralized matrix and enzymes to dissolve organic matrix
    • followed by osteoblasts; in this way, bone is constantly renewed and can strengthen when needed
    • Bone-chewing
  13. Important role of osteoblasts and osteoclasts
    keeping blood calcium and phosphorus within normal limits, so they are controlled by hormones
  14. two components of bone
    inorganic and organic
  15. inorganic part of bone
    • primarily hydroxyapatite ~ Ca5(PO4)3(OH)
    • Is a compound of calcium, phosphate, and hydroxyl groups held together by ionic bonds
    • this forms the rigid, brittle inorganic matrix of bone
  16. Organic part of bone
    mostly made up of collagen type I along with several minor proteins
  17. Why do we need both mineral (inorganic) and organic (collagen) components of bone working together?
    • If theres too much mineral, bone becomes too brittle and fractures easily
    • If bone has too much collagen, bones are soft and pliable
  18. osteogenesis imperfecta
    • "brittle bone disease"
    • having too much mineral in the bone, which causes it to be brittle and fracture easily
  19. rickets
    • happens in children, when their bones have too much collagen making them soft and pliable, making characteristic bent bones
    • happens in absence of D vitamins, children are unable to absorb sufficient calcium to lay down the large amount of mineralized bone they need
    • in adults it's called osteomalacia
  20. osteomalacia
    • happens in adults, when their bones have too much collagen, making them soft and pliable
    • the failure to make mineralized bone is not usually due to Vit D deficiency, but metabolic disturbances, cancer, or chemotherapy for cancer which can cause problems with calcium homeostasis
    • In children, it's called rickets
  21. Two main types of bone
    • each has a different microscopic structure
    • compact and spongy
    • *most bones have both
  22. Compact bone
    • hard, dense tissue
    • provides structural support and strength
    • made up of osteon's
  23. osteon
    • the basic structural unit of compact bone
    • cylinders of bone that runs along length of bone
    • each consist of a series of concentric lamellae; center structure is a canal that runs the length of the bone, carrying blood and lymphatic vessels
    • *another, older, name is Haversian systems
  24. lamellae
    • the concentric rings that make up each osteon
    • singular: lamella
  25. central canal
    • the center structure of an osteon, runs the length of the bone, carrying blood and lymphatic vessels
    • *another, older, name are haversian canal
  26. lacunae
    • small spaces btwn the lamellae which contain the osteocytes
    • singular: lacuna
    • *think of lacunae = "cunt, get home", since they 'house' the osteocytes
  27. canaliculi
    • small channels which join adjacent lacunae
    • "little canals"
    • (these were the "arm holes" they communicate with)
  28. Perforating canals
    • run radially in long bones to join adjacent central canals
    • *also called Volkmann canals
  29. spongy bone
    • made up of trabeculae
    • location of bone marrow
    • found in marrow cavity of long bones like femur and humerus
    • some bones (like the skull) are almost entirely made of spongy bone w just a thin shell of compact bone on outside
  30. structure of spongy bone
    • There are seveal loosely-organized rings, not as regular as lamellae of osteons, but still have lacunae containing osteocytes and with canaliculi containing the lacunae
    • Several of these loosely organized layers form trabeculae 
    • osteoclasts and osteoblasts are found around outside of trabeculae
  31. trabeculae
    • spiky projections in spongy bone
    • made from several loosely organized layers of lacunae with canaliculi
    • osteoclasts and osteoblasts lie along surface of each trabeulae
  32. cartilage
    • also makes up part of skeletal system
    • functions include: forming flexible skeletal structures, joining bones at synarthroses, lining joint surfaces in synovial joints, and forming scaffolding for new bone formation
    • *in fetuses and very young children, many of the future bones are completely cartilaginous
  33. three types of cartilage
    • hyaline cartilage
    • fibrocartilage
    • elastic cartilage
  34. hyaline cartilage
    • gets name from it's resemblance to glass: shiny and translucent
    • found lining joints and forms much of nose & ribs
    • has great deal of ground substance with no apparent structure
    • living cells (chondrocytes) that lay down cartilage are found in lacunae, here and there amongst the glassy ground
    • most cartilage in body is hyaline
  35. fibrocartilage
    • more fibrous in appearance and structure
    • chondrocytes found in lacunae, ground substance has collagen fibers 
    • found in disks btwn vertebrae, in pubic symphysis where two halves of pelvis are joined, and in meniscus of joints
  36. elastic cartilage
    • has elastin fibers in place of collagen fibers found in fibrocartilage, but otherwise similar structure
    • found in ear and epiglottis, which are two structures that need to be flexible and snap back into shape when moved and released
  37. role of dense regular connective tissues in skeletal system
    • represented by ligaments and tendons
    • striated appearance due to oriented collagen fibers
  38. ligaments
    • band-like structures that strap one bone to another
    • strong parallel orientation of collagen fibers give ligaments a striated appearance
  39. role of dense irregular connective tissue in skeletal system
    makes up very important structure = periosteum
  40. periosteum
    • a thin membrane made of dense irregular connective tissue that surrounds bone
    • has rich blood supply and plenty of nerve endings
    • connects tendons and ligaments to bones
    • also important in bone repair and remodeling
    • *it's source of both blood (swelling) and pain when you break a bone
  41. features of long bones
    • bones that are longer than they are wide
    • roughly cylindrical
    • Ex: femur, tibia and fibula, humerus, radius and ulna, and phalanges
  42. three natural parts of long bone
    epiphysis, diaphysis, metaphysis
  43. epiphysis
    • at either end of long bone
    • usually knobby ends of bone and form joint surfaces
    • where new bone develops in children
  44. diaphysis
    the shaft of a long bone
  45. metaphysis
    lays between the diaphysis and epiphysis, on either end of long bone
  46. epiphyseal plate
    • a specialized region inside the epiphysis, site of growth plate
    • under the control of hGH (human growth hormone)
    • therefore, when hGH is present, the epiphyseal plate continues to grow; when hGH levels drop, the plates "close" or become mineralized
  47. epiphyseal line
    • the remnant of the epiphyseal plate in adults who are done growing
    • possible to see as a landmark in conventional x-rays of bone
  48. Two strategies used to form bone
    • endochondral bone formation
    • intramembranous bone formation
  49. endochondral bone formation
    • bone formation using a cartilage "model" to shape the bone; cartilage is eventually replaced with compact or spongy bone
    • happens of the epiphyseal plate and other locations of bone growth
  50. primary ossification center
    appears in center of forming bone, where the diaphysis will be
  51. What happens btwn primary ossification center to secondary ossification center?
    • In center of developing bone (cartilage) primary ossification develops, starts laying down nucleus of spongy bone, growing outward toward ends
    • Eventually end up with just cartilage in ends of bone, future epiphysis
    • Then secondary ossification center forms
    • left over wedge of cartilage is epiphyseal plate
  52. secondary ossification center
    • develops near joint surface in in epiphysis
    • as both ossification centers expand, the leftover region of cartilage btwn them is where the epiphyseal plate lies
  53. intramembranous bone formation
    • same as endochondral bone formation, the future bone begins as cartilaginous model
    • are multiple ossification centers that start as islands and then spread outward
    • as they spread, spongy bone is formed
    • along the outside of the bone, the spongy bone eventually remodels to a thin shell of compact bone w spongy remaining in center
    • In bones of skull and other flat bones
  54. Describe how balance btwn osteoblasts & osteoclasts is critical
    • If osteoblastic activity is greater than osteoclastic: calcium is deposited into inorganic matrix, bone becomes thicker and stronger
    • If osteoclastic activity is greater than osteoblastic activity: calcium is released from inorganic matrix into bloodstream, bone becomes thinner and weaker
    • The balance btwn the two osteo-cells controled by hormones
  55. Two hormones that control osteoclast and osteoblast activity
    • Parathyroid hormone (PTH)
    • Calcitonin (CT)
  56. Parathyroid hormone
    • if blood calcium gets too low, released from set of small pea-shaped glands next to thyroid
    • increases osteoclastic activity: which breaks down the mineralized portion of bone and calcium (and phosphate) is released into the bloodstream
    • body sees bones as calcium reservoir
    • inhibits osteoblasts, increases blood Ca++ , decreases bone formation
    • increased blood calcium levels trun hormonal switch "off"
  57. For every molecule of hydroxyapatite the body breaks down, how much calcium do you get?
    10 calcium atoms
  58. Negative feedback loop vs. positive feedback loop
    • negative is self controlling, cannot spin out of control if overstimulated. Ex: blood pressure
    • positive isn't self controlling, only shut down when system is depleted or prob. corrected. Ex: childbirth. rarely used
  59. Calcitonin
    • made by parafollicular cells (C cells) in the thyroid gland
    • released when calcium is high; stimulates osteoblasts, inhibits osteoclasts, decreases Ca++, increases bone formation
    • absorb calcium from the bloodstream and deposit it as hydroxyapatite in bone
    • *think  Calcitonin = theres a ton of calcium, too much!
  60. Summary of Low Blood Calcium levels
    Low blood Ca++ → parathyroid releases PTH → PTH stimulates osteoclasts → osteoclasts release calcium from bone → blood calcium returns to normal and PTH release stops
  61. Summary of high blood calcium levels
    High blood Ca++ → thyroid releases calcitonin → calcitonin stimulates osteoblasts → osteoblasts deposit calcium in bone → blood Ca++ returns to normal and calcitonin release stops
  62. calcitriol
    • a third hormone released from the kidneys when they detect low blood Ca++ 
    • works in digestive system to increase the absorption of calcium from foods
    • helps blood and PTH restore normal Ca++ levels
  63. Two D vitamins
    • Vit D2 (ergocalciferol) and Vit D3 (cholecalciferol)
    • are made in skin w help of UV-B light (natural sunlight)
    • important in management of calcium
    • help in intestinal absorption of calcium in foods
  64. process of constant bone remodeling
    a wedge of osteoclasts form a cutting cone; while a wedge of osteoblasts come along behind in a closing cone and seal up the cavity that is formed
  65. Bone growth/remodeling in Children
    • *remember that there is constant remodeling of bone throughout our life
    • children are influence by hGH (human growth hormone) and the formation of bone at ossification centers, at epiphyseal plates of long bones and at multiple ossification centers in flat bones
    • hGH levels are high in childhood; after puberty levels decrease and epiphyseal plates "close"
  66. osteoporosis
    • literally means "holes in bones", disease which weakens bone
    • happens with elderly who have very low levels of hGH and tend to have problems with calcium absorption and homeostasis
  67. if a tumor makes hGH in adults...
    endochondral ossification is impossible but membranous bone formation can continue
  68. how do bones respond to stress?
    All bones respond to stress; in children, bones are less responsive to weight-bearing exercise, but in adults, moderate stress thickens bone and promotes formation of bone
  69. Good vs. bad stress for bones
    • stress on bones increases bone formation
    • Good stress: in adults, weight-bearing exercise increases bone thickness (not length) - increases blood supply in periosteum, which surrounds blood vessels and forms new osteons
    • Bad stress: friction in joints causes formation of bone spicules
  70. drugs used to treat osteoporosis:
    • Bisphosphonates = stabilize hydroxyapatite and make it more difficult for osteoclasts to break down mineralized bone (Fosamax, Actonel, Didronel)-(Did Fox Act?)
    • Taking oral calcium to ensure calcium absorption from digestive tract is maximal
    • *easier to inhibit osteoclast than to stimulate osteoblast
  71. Why do some pts on glucocorticoid therapy and some diabetes drugs have osteoporosis as a side effect?
    these drugs inhibit osteoblasts, and create an imbalance where osteoclasts are working faster than osteoblasts
  72. axial skeleton
    • axial = central
    • consists of those bones that are in the center of the body, from head to coccyx
    • skull, vertebrae, ribs and sternum
  73. appendicular skeleton
    • appendicular = "attached"
    • bones that form the structure of upper and lower extremities
    • in upper extremities include scapula & clavicle (cause they stabilize the shoulder girdle), bones of arm, forearm, wrist and hand
    • in lower extremities, includes bones of thigh, leg, ankle, foot, and pelvis (which is actually 3 bones joined together, is included cause stabilized lower extremity and forms socket of hip joint)
  74. short bones
    • are about as long as they are wide
    • includes carpal bones and tarsal bones
  75. flat bones
    • the bone equivalent of squamous cells; are wide and thin
    • includes sternum
  76. irregular bones
    • garbage category for bones that don't have any definable shape
    • includes vertebrae
  77. sesamoid bone
    • only normal sesamoid bone is patella
    • "like a sesame seed"
    • small, round, flat bone that can arise as the result of trauma to muscle as isolated small bones
  78. 4 large flat bones of skull
    frontal, parietal, temporal, occiptal
  79. lacrimal bone
    • in orbit of eye
    • "lacrimal" refers to structures associated with tears (crying)
  80. maxilla
    the upper jawbone
  81. mandible
    lower jawbone
  82. zygomatic bone
    has prominent zygomatic arch, forms the high cheekbones
  83. ethmoid bone
    • forms the interior upper ceiling of nasal sinuses
    • nerves carrying smell information pass through olfactory foramina in the sponge-like cribriform pate
  84. hyoid bone
    a horseshoe-shaped, "floating" bone in the neck
  85. nasal bone
    a small bone that forms the bridge of nose
  86. palatine bone
    forming roof of mouth (palate)
  87. sphenoid bone
    • "batwing" shaped bone that cowboy rides
    • contains optic foramen, hypophyseal fossa
    • also has an oval-shaped hole (foramen ovale) which allows the passage of several nerves and blood vessels
  88. optic foramen
    • found in sphenoid bone, forms a hole for optic nerve to pass from eye to brain
    • The foramen right in front of cowboy; could be used for "sight holes" to see while riding his bat
  89. hypophyseal fossa
    • in sphenoid bone, forms a ditch that holds the pituitary gland (hypophysis)
    • Where the cowboys saddle seat is
  90. vomer
    bone btwn ethmoid, maxilla and palatine
  91. olfactory foramina
    foramina which nerves for smelling pass through ethmoid bone
  92. cribriform plate
    sponge-like part of ethmoid bone which contains the olfactory foramina
  93. foramen magnum
    of the occipital bone, a huge hole which allows the spinal cord to exit the skull
  94. vertebral column
    • 5 regions:
    • Cervix = neck, 7 cervical vertebrae
    • Thorax = chest, 12 thoracic vertebrae
    • Lumbar = loin, 5 lumbar vertebrae
    • Sacral = "holy", 5 sacral vertebrae, fused
    • Coccyx = several coccygeal vertebra (# varies per individual), fused
  95. structures of the vertebrae
    • Largest part is the body
    • Joint btwn 2 adjacent bodies is filled w disk of fibrocartilage, called intervertebral disc
    • Two transverse processes extend laterally; a pedicle connects each of these to body
    • along midline is a spinous process which protrudes posteriorly; is joined to transverse processes by laminae
    • These parts form a vertebral foramen that contains spinal cord
    • *different vertebra vary
  96. atlas
    • C1 vertebrae
    • recall that Atlas in Greek mythology held up the earth
    • no body, minimal spinous process
    • holds up the head
  97. atlanto-occipital joint
    • the joint btwn the occipital bone of skull and atlas
    • allows us to nod up and down, saying yes
  98. axis
    • C2 vertebrae; small body
    • articulates (forms a joint) with the atlas that allows for head rotation
    • has dens which is a tooth-like "peg" which projects superiorly into the vertebral foramen of atlas
  99. transverse ligament
    attached to C1, wraps around dens to hold in place but allows for head rotation, shaking head in "no"
  100. cervical vertebrae
    • C3 - C7 are more "typical"
    • a unique feature of C3 - C7 is they are bifid (two-pronged) spinous process
  101. vertebra prominens
    • C7, the last of the cervical vertebrae
    • called such because it's prominent
    • can feel when palpate back, right below neck
  102. thoracic vertebrae
    only ones that articulate with ribs (12 thoracic vertebrae articulate -make joints- with 12 ribs)
  103. two points at which each rib (left and right) touches a vertebra
    the transverse process of a vertebra touches the tubercle of a rib

    The body of the vertebra touches the head of a rib
  104. where do thoracic vertebrae make joints with each other?
    at the inferior articular facet and superior articular facet
  105. Lumbar vertebrae
    • designed to carry a large amount of weight; therefore have thick, strong body
    • gives them the appearance of a "scotty dog" in lateral medial x-ray views
  106. sacrum & coccygeal vertebrae
    • Sacrum is made up of 5 fused vertebrae (S1 - S5)
    • Coccyx is made up of 3-4 fused vertebrae (# varies)
  107. transitional vertebrae
    • a relatively common anatomical variation
    • includes lumbarization of S1 and sacralization of L5
  108. lumbarization
    • of S1 vertebrae
    • In 10% of humans, there is an "extra" joint btwn S1 and S2, then S2-S5 are fused.
    • Because S1 is acting like a lumbar vertebra, it's called lumbarization of the S1 vertebra
  109. sacralization
    • of L5
    • In 14% of people (ex: 1 in 7), the L5 vertebrae is fused w the S1-S5 stack to form six fused vertebrae.
    • Because L5 is "acting" like a sacral vertebra, it's called sacralization of L5 vertebra
  110. Thorax
    • the chest
    • thoracic skeleton is made up of sternum + 12 pairs of ribs
  111. naming of ribs
    T1 articulates with the first rib, T2 articulated with the 2nd rib... hence, ribs are numbered superior to inferior
  112. costal cartilage
    • a type of hyaline cartilage
    • make the connection btwn true ribs (1-7) and the sternum
  113. false ribs
    • ribs 8-10
    • called false cause the use rib 7 to articulate with sternum, rather than making connection directly
    • again, it's hyaline costal cartilage that makes the connection
  114. glenoid fossa
    the socket for the head of the humerus; on scapula
  115. what bones support the shoulder (pectoral) girdle
    the clavicle and scapula; together forming the glenoid fossa
  116. "arm" vs. "forearm"
    • Arm is the structures btwn the shoulder joint and elbow joint
    • Forearm includes structures btwn the elbow and wrist
  117. bones of forearm
    • radius and ulna, articulate with distal humerus at elbow joint
    • *Radius is Rad...(thumbs up) is on thumb side
    • Ulna associated with pinky
  118. thumb
  119. pelvis
    • supports the lower extremity
    • has 3 bones on each side (6 total): ilium, ischium, pubis
    • depression forming a large socket for head of femur is called acetabulum
  120. ilium
    • one of 3 bones of pelvis
    • forms a large, flat, curved, flared bone laterally (flank)
  121. ischium
  122. pubis
  123. sacroiliac joint
    the joint that joints ilium and sacrum
  124. pubic symphysis
    where the two halves of pubis come together
  125. specific terms for lower extrmity
    • btwn hip and knee is the thigh
    • btwn knee and ankle is leg
  126. great toe
  127. bone shapes
    reflect points of attachment by tendons or ligaments
  128. condyle
    • meaning knuckle
    • common name of bone shape
    • Ex: lateral and medial condyles of tibia
  129. epicondyle
    • on top of a condyle, "next to knuckles"
    • common name of bone shape
    • Ex: the medial and lateral epicondyles of femur at knee joint
  130. foramen
    • "window" or hole; for passage of nerves or blood vessels
    • common name of bone shape
    • Ex: optic foramina
  131. fossa
    • "ditch"; describes a shallow dish-like depression or groove
    • common name of bone shape
  132. process
    • projection or spike of bone (ex: xiphoid process)
    • common name of bone shape
  133. spine
    • like process but pointy
    • common name of bone shape
    • Ex: spinous process or ischial spine of pelvis
  134. trochanter
    • attachment point for large muscles of hip
    • means "runner"
    • common name of bone shape
    • Ex: femur has greater and lesser trochanters
  135. trochlea
    • pulley
    • common name of bone shape
    • Ex: one in elbow and one in eye socket
  136. tubercle
    • "tuber" means potato
    • means little potato
    • common name of bone shape
    • Ex: greater and lesser tubercles of humerus
  137. tuberosity
    • "tuber" means potato, so potato like bump
    • common name of bone shape
    • Ex: tibial, radial, and ischial tuberosities
  138. fontanels
    • areas in the fetus and newborn where there are bands of fibrocartilage btw the developing bones of the skull 
    • this arrangement allows the head to fit through birth canal and also allows for some continued growth of brain after birth
  139. Anterior fontanel
    • place where the two (L & R) frontal bones join the two (L & R) parietal bones
    • the big soft spot on top of head
  140. anterolateral fontanel
    where the temporal, parietal, and frontal bones are joined
  141. posterior fontanel
    along midline btwn the parietal and occipital bones
  142. posterolateral fontanel
    where the parietal, occipital, and temporal bones meet
  143. sutures
    • zig-zag lines that hold the bones of the skull together tightly
    • what remains after the first few months of life when the fontanels fuse and become bone
  144. only movable joint in the adult skull
    the temporomandibular joint
  145. pelvis differences in female vs. male skeleton
    • pelvis is one of few bony structures that is substantially different btwn males and females
    • Females have a wider pubic arch and pelvic brim
  146. pubic arch
    • the angle btwn the ischial tuberosities
    • In females, usually greater than 90°
    • In males, usually less than 90°
  147. pelvic brim
    • also called pelvic inlet; the oval region defined by medial aspect of ilia
    • is larger in females
  148. greater sciatic notch
    • notch in pelvis for sciatic nerve
    • in females, the coccyx projects further posteriorly, making the notch larger in females
  149. two systems for classifying joints
    • functional classification
    • anatomical classification
  150. functional classification of joints
    • based on movement
    • synarthrotic - You've sinned, your not moving
    • amphiarthrotic
    • diarthrotic
  151. synarthrotic joints
    • not capable of functional movement
    • Ex: joints in the skull
  152. amphiarthrotic joints
    • slightly moveable
    • Ex: ribs, pubic symphysis (during childbirth)
  153. diarthrotic joints
    • fully moveable
    • Ex: shoulder, elbow, hip, etc.
  154. anatomical classification of joints
    • also called structural, based on how the bones at the joint are held together
    • Fibrous, cartilaginous, and synovial
  155. fibrous joint
    • band of dense irregular connective tissue connects two bones, or bone & tooth
    • Ex: what holds the bones of the skull together, what holds teeth in place
  156. gomphosis
    • *Technically, since teeth are not bones, not actually a fibrous joint. But because teeth and bones are so similar, most people would classify this as a fibrous joint
    • is a joint that isn't moveable, but can move a little bit at a time
  157. cartilaginous joint
    • where bones are held together by cartilage, no synovial cavity
    • Ex: btwn true ribs and sternum
  158. synovial joint
    • a synovial cavity is present and filled with synovial fluid
    • articular cartilage covers the bones where they are in contact
    • entire structure is contained by joint capsule
  159. functional vs. anatomical classification of joints
    • Some joints are easy to classify using both schemes
    • Ex: joints btwn bones of skull are clearly synarthroses in functional classification and fibrous joints in the anatomical classification
  160. synovial joints
    • typically diarthroses in functional classification
    • structures of synovial joint are specialized to allow freedom of movement w/o friction or strain
    • Key features: bones, articular cartilage, joint capsule, bursa
  161. articular cartilage
    • both reduces friction and provides a cushion at the joint
    • provides a slightly elastic but strong tissue at the place where joint motion occurs
  162. joint capsule
    • set of membranes which hold the bones in correct position and also encloses the fluid portion of the joint
    • Made up of strong outer fibrous capsule, and inner synovial membrane that secretes synovial fluid
  163. bursae
    • fluid-filled sacs near joint that help reduce friction btwn tendons and bone
    • found at points where tendons and ligaments move across bone
  164. One "feature" of synovial joints since they must allow for free movement...
    they are often structurally imperfect and subject to damage
  165. temporomandibular joint
    • btwn the temporal bone and the mandible; has articular disc
    • *has double barreled synovial cavity.. so has 2 compartments filled with synovial fluid, articular disc inbetween
    • freely movable joint which has all the usual features of a diarthrosis (functionally) and a synovial joint (anatomically): 2 bones, & joint capsule filled w fluid
  166. articular disk
    • mostly made of type I collagen, halfway btwn the cartilaginous surfaces
    • divides the synovial cavity into two parts: superior and inferior compartment
    • Ex: temporomandibular (TMJ), if it becomes inflamed, causes pain
  167. Movements at Synovial Joints
    • gliding movements
    • angular movements
  168. gliding movements
    • referring to synovial joint
    • are side to side and do not change the angle of the joint
    • Ex: intercarpal and intertarsal joints
  169. angular movements
    • referring to synovial joint
    • change the angle of a joint
    • Flexion/extension/hyperextension
    • adduction/abduction
    • lateral flexion
    • circumduction
  170. flexion
    movements that decrease the angle of a joint
  171. extension
    movements that increase the angle of a joint
  172. hyperextenstion
    when an extension movement (increasing the angle of a joint) reaches the anatomical position and keeps going
  173. lateral flexion
    possible for the back only, bending sideways
  174. abduction
    • a motion that takes a body part away from the midline
    • *think "if someone comes into your house and abducts you, they are taking you away"
  175. adduction
    a motion that brings a body part closer to the midline
  176. movements of the radioulnar joint
  177. pronation
    • moving the radioulnar joint so that the palm faces posteriorly
    • *remember anatomical position
  178. supination
    • moving the radioulnar joint so the palm faces anteriorly
    • *scooping up soup
  179. circumduction
    • a circular/rotational movement with the shoulder or hip joint
    • *neither flexion/extension, neither adduction/abduction
  180. six types of synovial joints
    • Planar
    • hinge
    • pivot
    • condyloid
    • saddle
    • ball-and-socket
    • "Please Pasture Hank Cause he's Slightly Boney"
  181. example of planar joint
    • btwn navicular and 2 & 3rd cuneiform bones in tarsus
    • would make gliding movements
  182. hinge joint
    duh... ex: joint btw humerus and ulna at elbow
  183. pivot joint
    • Ex: radius and ulna
    • rotates
  184. condyloid joint
    Ex: btw radius and lunate & scaphoid
  185. saddle joint
    Ex: trapezium and metacarpal thumb
  186. ball and socket joint
    duh... head of femur and hip bone
  187. 3 common problems with aging joints
    • osteoarthritis
    • bursitis
    • sprains
  188. osteoarthritis
    • lose of synovial fluid & breakdown in articular cartilage - causing inflammation
    • some degree is inevitable with aging, part just become warn and direct contact btwn bones produce osteophytes
  189. osteophytes
    • little spikes produced by remodeling in response to bone rubbing on bone
    • cause further damage to joint, and process spirals downward
  190. bursitis
    inflammation of bursa which allows tendons and ligaments to slide past bones at joints.
  191. sprains
    • microscopic tears in ligament or tendon
    • obvious tears, where collagen fibers completely separate from each other, are also called sprains
    • Orthopedic surgeons use a grading system (1-3) to grade degree of tearing, with 1 describing microscopic tears and 3 describing total ripping apart of ligament
  192. strain
    tears in a muscle of the tendon that connects muscle to bone