Study of bone structure and treatment methods
Osteology
Supports and protects- assist in movement -mineral homeostasis -blood cell production -triglyceride storage
Bone tissue functions
Cylindrical portion
Diaphysis (saft) (long bone)
Distal and proximal ends
Epiphyses (long bone)
Joins diaphysis with epiphyses -ingrowing bones
Metaphysis (long bone)
Growth plate,involved in bone growth and length
Ephiphyseal (metaphysis)
At age 18-21 ______ stops growing in length and epiphyseal plate is replaced by epiphyseal line -rich in blood and nerve supply
Bones
Hyaline cartilage covering epiphysis in synovial joints
Articular cartilage
Outer bone covering- permits bone growth in thickness -attachment point for ligaments and tendons
Periosteum
Space in diaphysis
Meduallary cavity
Membrane lining medullary cavity
Endosteum
Matrix surrounding ________ consists of 25% water 25% collagen fiver and 50% salts
Bone cells
The most abundant slat hardens bone
Calcium phosphate
Contribute to tensile strength
Collagen fibers
Bone stem cells that divide to form osteoblast
Osteogenic
Immature bone building cells
Osteoblast
Mature bone cells that maintain bone tissue
Osteocytes
Function in bone resorption; crush bone, controlling blood calcium levels
Osteoclasts
Most common and strongest type -forms exterior of all bones -blood vessels penetrate compact bone though horizontal perforating canals
Compact (dense bone)
Structural units of compact bone consisting of concentric lamelle, lacunae, canaliculi
Osteons (compact bone)
Rings of calcified bone matrix
Concentric lamelle (osteons)
Spaces containing osteocytes
Lacumae (osteons)
Small channels permitting osteocytes to exchange materials with blood
Canaliculi (osteons )
Appeals like sponge that lightens bone -some adults spongy bone contain red bone marrow including axial skeleton, pelvic bone and ends of long bones
Spongy (cancellous) bone
Thin plates of bone
Trabeculae (spongy bone)
Blood cell production
Hemopoesis (spongy bone)
Measure bone density -dark areas; hot spots may indicate bone cancer -Lighter areas; cold spots may indicate osteoporosis
Bone scans
Intramembraneous ossification endochondral ossification
Bone formation 2 types
Brings before birth -bones are formed directly from mesenchyme; cranial bones and clavicle
Intramembranous ossification
Ossification center develop ; osteoblasts secrete matrix -calcification occurs ; salts hardens matrix -spongy bone formed -compact bone replaces most spongy bone
Intramembraneous ossification 4 steps
Most common methos involves bone forming directly from cartilage
Endochondral ossification
Cartilage model develops; immature cartilage cells called chondroblasts form- growth of cartilage model; interstitial growth lengthens cartilage ; appositional growth thickens cartilage by depositing cartilage on outer surface -primary ossification center develops; bone forms in diaphysis replacing most cartilage
Endochondral ossification 6 steps (1-3)
Medullary cavity develops -secondary ossification center develops; bone forms in epiphysis -epiphyseal plate and articular cartilage develop
Endochondral ossification 6 steps (4-6)
A connective tissue that remodels and repairs on a daily basis -makes up 18% of body weight
Bone tissue