Test 2 Flashcards
Synarthrosis
Immovable joint, plural = syntharoses
Amphiarthrosis
Slightly moveable joint, amphiarthtoses
Diarthrosis
Freely moveable joint, plural = diarthroses
Three structural types of joints
- Fibrous joints 2. Cartilaginous joints 3. Synovial joints
Fibrous joint
No synovial cavity; bones held together by dense CONNECTIVE tissue, rich in collagen fibers
Cartilaginous joints
No synovial cavity, bones held together CARTILAGE
Synovial joints
+synovial cavity, United with the dense irregular CT of an articular capsule and often accessory ligament
Three types of fibrous joints
- Sutures - skull 2. Syndesmoses 3. Interosseus Membranes
Sutures location
Only found between bones of the skull
Gomphosis
Dental-alveolar joint = cone-shaped peg into a socket-teeth and their sockets found in the maxilla/mandible
Periodontal disease
Degeneration and inflammation of this ligament; may permit movement at that point. Periodontal ligament connects the tooth to the socket, permitting no matter movement (synarthosis)
Interosseous Membrane location
Between radius and ulna Between tibia and fibula
Name the three functional types of joints
- Synarthrosis 2. Amphiarthrosis 3. Diarthosis
Osteology
the study of bone structure and the treatment of bone disorders.
What are the Basic Functions of Bone and the Skeletal System?
- Support (structural framework of the body. Supports soft tissue and points of attachments for tendons). 2. Protection (protection of internal organs-pelvis/ribs; spine; skull) 3. Assistance in movement (provide a surface for muscular attachment; contraction of muscles will pull on bones to produce movement) 4. Mineral homeostasis (calcium & phosphorous storage) 5. Blood cell production (Red Marrow-Hematopoiesis) 6. Triglyceride storage (yellow marrow mainly adipose cells)
Sharpey_s fibers (perforating fibers)
thick bundles of collagen that extend from the periosteum into bone extracellular matrix.
What is the most abuntant mineral salt?
Calcium Phosphate (CA3(PO4)2)
Most abundant to least abundant in bone histology
Crytalized Mineral Salts (55); Collagen Fibers (35); Water (15)
What are the four types of cells?
Osteoprogenitor; Osteoblast; Osteocytes; Osteclasts
Functions of Osteoclasts.
Resporption; Regulation of serum Calcium
Unit of bone
Osteons
What do ateries do?
carries blood TO bone tissue
What do veins do?
carries blood away from bone tissue
PERIOSTEAL ARTERIES
small arteries accompanied by nerves; enter diaphysis of the bone through perforating (Volkmann_s canals). Function: supply periosteum and outer part of compact bone.
NUTRIENT ARTERIES
found near the center of the diaphysis; Function: supply inner compact bone tissue of diaphysis and spongy bone tissue and red bone marrow as far as the epiphyseal plates (lines)
METAPHYSEAL ARTERY
Course: enter the metapyses of a long bone (together with the nutrient artery); Function: supply bone tissue of the metaphyses & red marrow
EPIPHYSEAL ARTERY
Course: enter the epiphyseal; Function: supply red marrow and the bone tissue of the epiphyses
NUTRIENT VEINS
one or two veins will accompany the nutrient artery and exit the diaphysis
Numerous EPIPHYSEAL and METAPHYSEAL VEINS
accompany their respective arteries and exit through the epiphyses and metaphyses.
Many PERIOSTEAL VEINS
accompany periosteal arteries and exit via the periosteum
Why do they do bone marrow biopsys?
typically go into the hip; inserted into the middle of the bone to withdraw a sample of red bone marrow to examine it for conditions such as leukemia; metastatic neoplasm (tumors); lymphoma; Hodgkin_s and aplastic anemia.
Embryonic skeleton is comprised of?
Mesenchyme
Bone formation occurs in which two patters?
Endochondral ossification and intramembranous ossification
Ossification
the process by bone forms.
Osteogenesis
the process by which bone forms.
Intramembranous ossification
_membrane_ [bone forms directly within mesenchyme; arranged in sheet-like layers resembling membrane
Endochondral ossification
_cartilage_ [bone forms w/in hyaline cartilage that develops from mesenchyme]
Intramembranous ossification details
Bone types involved - more flat bones ; embryonic model - a sheet of dense fibrous CT ; stem cells involved - fibroblasts; osteoblasts ; progression of developing tissue types - Dense fibrous CT ; Marrow space in adult bone - unlikely
Endochondral ossification details
Bone types involved - most long; short; and irregular bones ; embryonic model - dense fibrous CT replaced by hyaline cartilage matrix ; stem cells involved - fibroblasts; chondroblasts; osteoblasts ; progression of developing tissue types - Dense fibrous CT to Hylaine Cartilage to Bone; Marrow space in adult bone - likely
Appostional growth
an increase in size by the addition of new tissue or similar material at the periphery of a particular part or structure; as in the addition of new layers in bone and tooth formation
Interstital growth
growth from a number of differnet centers within an area; in contrast with appositional growth; it can occur only when the materials involved are nonrigid; such as cartilage
Details regarding the closure of the epiphyseal plate (growth plate)
- End of adolescence [women;18 and men; 21] due to estrogen and testosterone 2. Fracture/injury where there is a cessation in cell division 3. Anabolic steroid use as adolescent.
Hormones/Chemicals involved with Epiphyseal Growth Plate:
- Growth hormone (GH) stimulates chondrocytes to synthesize and respond to insulin growth factor-I (IGF-1) 2. IGF-I produced locally (along with IGF-I produced by the liver) stimulates cell division 3. Estrogen and testosterone stimulate closure of epiphyseal plates.
Bone remodeling
the ongoing replacement of old bone tissue by new bone tissue
Bone resportion
removal of minerals and collagen fibers from bone osteoclasts [destruction of bone ECM]
Bone deposition
addition of minerals and collagen fibers to bone by osteoblasts [formation of bone ECM]
How many times is the distal femur replaced?
replaced about every four months
Is the shaft of the femur replaced?
will not be replaced during a person’s lifetime
Functions of remodeling
- Replaces old bone 2. Removes injured bone; replaces it with new bone
Triggers for bone remodeling
- Exercise 2. sedentary lifestyle 3. changes in diet
Benefits of bone remodeling
- removes injured bone 2. bone that is subject to heavier loads can grow stronger and thicker 3. bone shape can be altered for proper support; based on the stress patterns experienced 4. new bone is more resistant to fracture than old bone
What minerals cause bone growth?
larger amounts of calcium and phosphorus are needed while bones are growing; smaller amounts magnesium; fluoride; manganese
What vitamins cause bone growth?
Vitamin A=stimulation of osteoblast activity; Vitamin C for synthesis of collagen; Vitamin=increases absorption of calcium from foods in the GI tract; into the blood; Vitamin K ad B12=synthesis of bone proteins
What hormone assists in shutting the epiphyseal plate?
Estrogen
Clinical Correlations of Fractures
will vary depending on the age; type of fracture and bone involved. Ultimate goal of fracture repair: 1. Realignment of bone fragments 2. Immobilization to maintain realignment 3. Restoration of function
Closed reduction
bones are brought into alignment by manual manipulation; where the skin remains intact.
Open reduction
bones are brought back into alignment by a surgical procedure using internal fixation devices such as screws; plates; rods; and wires.
Open compound fracture
Description: Broken ends of the bone protrude from the skin [closed fracture; does not break the skin]
Comminuted fracture
crumbled; Description: Bone is splintered; crushed or broken into pieces at the site of impact. Smaller bone fragments can be found between the two main fragments.
Greenstick fracture
Partial Fracture; one side of the bone is broken and the other side of the bone bends; similar to how a green twig breaks on one side and the other side stays whole. Occurs only in children whose bones are not fully ossified and contain more organic material than inorganic.
Impacted fracture
Description: The ends of the fracture bone are driven into the interior of the other
Pott’s fracture
Description: Fracture of the distal end of the lateral leg bone (fibula) with serious injury of the distal tibial articulation
Colles fracture
FOOSH; Description: Fracture of the distal end of the lateral forearm bone (radius) in which the distal fragment is posteriorly displaced.
Where is the major storage of calcium? (99%)
Bone
Hormonal Regulation of Calcium Exchange
How PTH increases serum calcium: Parathyroid Hormone (PTH): secreted by parathyroid glands. 1. Increases blood calcium level using a negative FB system 2. Acts on the kidneys to decrease the loss of calcium in the urine (more will be retained in the blood) 3. Stimulates the formation of calcitriol (active vitamin D); a hormone that promotes absorption of calcium from foods in the GI tract; into the blood.
Osteoporosis
loss of calcium from bone; This is literally _porous_ bone. Breakdown of bone occurs faster than bone can be formed.
Osteopenia
Low bone mass
Drug treaments for osteoporosis
- anti-resorptive drugs: slow down progression of bone loss 2. bone-building drugs: promote increase in bone mass
Rickets
a disease of children in which the bones become rubbery or soft and are easily deformed. New bone fails to form at the growth plates; resulting in a bowing of the legs and deformities of the skull; rib cage and pelvis.
Osteomalacia
adult rickets. New bone formed during remodeling fails to ossify.
Treatment for rickets and ostemalacia
Vitamin D supplementation and exposure to moderate sunlight.
Osteoarthritis
degeneration of articular cartilage; such that the bony ends touch; resulting in friction of bone against bone. This worsens the condition. This is usually associated with the elderly.
Osteomyelitis
Infection of the bone; characterized by high fever; sweating; nausea; chills; pain; pus formation; edema; warmth over affected bone and rigid overlying muscles. Most often caused by Staphylococcus aureus.
Bacteria can reach the bone through the following mechanisms:
- From the outside of the body through open fractures; penetrating wounds; orthopedic surgical procedures 2. Blood from ther sites of infection in the body (abscessed teeth; burn infections; UTI_s or upper respiratory infections) 3. Adjacent soft tissue infections (wounds in diabetes mellitus
Osteopenia
reduced bone mass due to a decrease in the rate of bone synthesis to a level that is too low to compensate for normal bone resorption. Any decrease in bone mass below normal. Osteoporosis is an example of this.
Osteosarcoma
Bone cancer that primarily affects osteoblasts and occurs most often in teenagers during a growth spurt.
Most common sites for osteosarcoma
Most common sites: 1. Metaphyses of femur (thigh) 2. Shin (tibia) 3. Humerus (upper arm) Most common sites for metastases: lung Treatment: multiple drug regimens of chemotherapy and removal of malignant growth (amputation of the limb).
Functions of Integumentary System
- Regulates body temperature 2. Stores blood 3. Protects body fro external environment 4. Detects cutaneous sensations 5. Excretes and absorbs substances 6. Synthesis of vitamin D
Which layers are apart of the skin?
Epidermis; dermis
What layer is not apart of skin?
Subcutaneous tissue
Epidermis layer composition
Keritinized stratified squamous epithelium
Name the 5 layers of skin
- Stratum Basale 2. stratum spinosum 3. stratum granulosum 4. stratum lucidium 5. stratum corneum
Types of cells in epidermis
Keratinocytes; melanocytes; intraepidermal macrophages; merkel cells
Melanin
a yellow-red or brown-black pigment that contributes to skin color and absorbs damaging UV light.
Epidermal growth-factor
The rate of cell division in the Stratum Basale increases when outer layers of the epidermis are stripped away (ie: abrasions; burns) Mechanism: unknown; but are regulated some from hormone-like proteins such as_
Dandruff
excessive amount of keratinized cells shed from the skin of the scalp
Principle layers of the dermis
- Papillary Region (thinner; superficial) 2. Reticular region (thicker; deep)
Dermal Papillae
small nipple shaped structures that project into the undersurface of the epidermis
Compentents of Dermal Papillae
Capillary loops (blood vessels); meissner corpusclues; free nerve endings
Melanin pigment
varies skin color from pale yellow to reddish brown
Pheomelanin
yellow to red