Please enable JavaScript.

Coggle requires JavaScript to display documents.

Bone Fracture (Long Bones (periosteum: covers the outer surface of the…

- - - - the outer, fibrous layer of dense irregular connective tissue protects the bone from surrounding structures., anchors blood vessels and nerves to the surface of the bone, and serves as an attachment sit for ligaments and tendons
      - the inner, cellular later inculdes osteoprogenitor cells, osteoblasts and osteoclasts.
- - - - calcification is imitated when he concentration of calcium ions and phosphate ions reaches critical levels and precipitate out of the solution, thus forming the hydroxyapatite crystals that depots in and around the collagen fibers.
    - - ossification begins in the embryo and continues as the skeleton grows during childhood and adolescence.
      - by the eighth through twelfth weeks of embryonic development, the skeleton begins forming from either thickened condensations of mesenchyme or hyaline cartilage model of bone
    - - bone growth within the membrane; thin layer of mesenchyme In these areas is sometimes referred to as a membrane
      - produces flat bones of the skull, some frontal facial bones, and the mandible, and central part of the clavicle
      - source of these bones is their the area of the future dermis
      - ossification centers form within thickened regions of mesenchyme beginning at the eighth week of development
        
        osteoid undergoes calcification
        
        woven bone and its surrounding periosteum form
        
        lamellar bone replaces woven bone, as compact bone and spongy bone form
    - - fetal hayline cartilage model develops
        
        cartilage calcifies, and a periosteal bone collar forms
        
        the primary ossification centers forms in the diaphysis
        
        secondary ossification centers form in the epiphyses
        
        bone replaces almost all cartilage, except the articular cartilage and epiphyseal cartilage
  - - - zone of resting cartilage
        
        zone of proliferating cartilage
        
        zone of hypertrophic cartilage
        
        zone of calcified cartilage
        
        zone of ossification
        
        walls break down between lacunae in columns, forming longitudinal channels. these spaces are invaded by capillaries and osteoprogenitor cells from the medullary cavity.
        
        new matrix of bone is deposited on the remaining calcified cartilage matrix
        
        composed of 2 or 3 laters of chrondocytes. minerals are deposited in the matrix between the columns of lacunae
        
        this classification destroys the chrondrocytes and makes the matrix appear opaque
        
        cease dividing and begin to hypertrophy in this zone
        
        the walls of lacunae become thin the chrondrocytes resorb matriculates as they hypertrophy
        
        undergo rapid mitotic cell division, enlarge slights, and become aligned like a stack of cans into longitudinal columns of flattened lacunae
        
        these columns are parallel to the diaphysis
        
        zone is farthest from the medullary cavity of diaphysis and new the epiphysis. composted of small chondrocytes distributed through the cartilage matrix. resembles mature and healthy hyaline cartliage
        
        securest epiphyseal plate
      - dependent upon growth of cartilage within the epiphyseal plate, 5 different zones that are continuous from the first zone nearest the epiphysis to the last zone nearest the diaphysis
    - - occurs within the periosteum
      - osteoblasts in the inner cellular layer or periosteum produce and deposit bone matrix within layers parallel to the surface, called external circumferential lamellae.
      - continues through a persons lifetime
  - - - produces by the anterior pituitary gland
      - affects bone growth by stimulating the liver to form another hormone called insulin-like growth factor
      - growth hormone and IGF directly stimulate growth of cartilage in the epiphyseal plate
    - - secreted by thyroid gland and stimulates bone growth by influencing the basal metabolic rate of bone cells
      - if working properly, thyroid hormone and growth hormone maintain normal activity in epiphyseal plate till puberty
    - - stimulate osteoblasts; promote epiphyseal plate growth and closure
    - - increased bone loss and, in kids, impair bone growth when there are chronically high levels of glucocorticoids
    - - inhibits osteoprogenitor cells from differentiating into osteoblasts; lasts when there are chronically high levels of serotonin
- - - - thin break caused by increased physical activity in which the bone experiences repetitive loads
    - - occurs when weakened by disease
    - - bone does not penetrate skin
      - healing takes 2 to 3 months
    - - one or both end of bone pierce overlying skin
- - - - cell secreted the matrix of cartilage and become embedded in it
      - produce and maintain the cartilage matrix
      - only cell in cartilage
    - - fine branching blood vessels that form a network between arterioles and venules
      - a tube w an internal diameter of hairlike thickness
      - sites of the transfer of oxygen and tore nutrients from the bloodstream to other tissues in the body
    - - stem cells of bone
      - form osteoblasts
      - synthesize the bone matrix
  - - - type of cell that synthesizes the extracellular mature and collagen
      - critical in wound healing
    - - will from chondrocytes in the growing cartilage matrix
      - help expand cartilage size whenever prompted to by hormones
    - - bone productions begins when he clotted blood formed by inflammation is replaced with fibrous tissue and cartilage
    - - cell that secrets the matrix for bone formation
      - build bones; control calcium and mineral deposition
    - - each of a sergers of partitions formed by bands of columns of connective tissue, especially a plate of the calcareous tissue forming cancellous bone
      - provide structural support to the spongy bone found at the end of long bones
    - - thickened layers of skin, usually on hands and feet, where friction repeatedly occurs
- - - - a hard (bony) callus forms
        
        a bone is remodeled
        
        final phase
        
        hard callus is persists for at least 3 to 4 months as osteoclasts remove excess bony material from both exterior and interior surfaces
        
        compact bone replaces primary bone
        
        fracture usually leaves a slight thickening of the bone, sometimes healing occurs with no present thickening
        
        during week 1 of injury , osteoprogenitor cells in the areas adjacent to the fibrocartilaginous callus became osteoblasts and produce trabaculea of primary bone
        
        the fibrocartilaginous callus is the replaces by hard callus
        
        the trabaculae of the hard callus grows and thickens for several months
        
        phase 3
      - regenerated blood capillaries infiltrate the fracture hematoma
      - first, the fracture hematoma reorganized into an actively growing connective tissue called procallus
      - fibroblasts pithing the procallus produce collagen fibers that help connect the broken ends of the bones
      - chrondoblasts in the newly growing connective tissue form a. defense regular connective tissue associated within the cartilage
      - eventually procallus becomes a fibrocartilaginous (soft) callus. this stage lasts about 3 weeks
      - phase 2