Appendicular Skeleton Anatomy PDF

Part 1 pectoral girdle Part 2 humerus Part 3 radius, ulna, carpals, metacarpals, and phalanges Part 4 pelvic girdle Part 5 femur https://www.youtube.com/watch?v=LRW0tFS0E-U Part 6 tibia, fibula, tarsals, metatarsals, and phalanges Part 7 [endochondral ossification step by step ] 1. star...

Part 1 pectoral girdle Part 2 humerus Part 3 radius, ulna, carpals, metacarpals, and phalanges Part 4 pelvic girdle Part 5 femur https://www.youtube.com/watch?v=LRW0tFS0E-U Part 6 tibia, fibula, tarsals, metatarsals, and phalanges Part 7 [endochondral ossification step by step ] 1. start with hyaline cartilage in fetus 2. blood vessels and osteoblasts grow into the perichondrium, thereby the perichondrium turns into periosteum 3. osteoblasts from bone collar: cover external hyaline cartilage with osteoid 4. primary/1o ossification center forms in center of diaphysis a. blood vessels grow into the bone b. osteoblasts and osteoclasts travel into the cartilage c. The osteoblasts secrete osteoid over any remaining hyaline cartilage forming trabeculae, thus creating spongy bone d. chondrocytes present start to die due to calcification (hydroxyapatite is laid down and the cells can't get nutrients, thus cartilage matrix breaks down 5. cartilage in the epiphysis continues to grow so bone becomes longer. Growth hormones promote the growth of the epiphyseal cartilage. 6. osteoclasts breakdown bone forming the medullary cavity within the diaphysis 7. epiphysis continues to grow since made of cartilage but the 10 ossification center from shaft keeps growing towards it. When chondrocytes die, they are calcified by osteoblasts. 8. when born, the epiphysis is still cartilage. A 20 ossification center forms in each epiphysis. Like primary ossification center except no cavity 9\. the epiphysis remains as spongy bone. where the two ossification centers meet, get the epiphyseal plate (still hyaline cartilage). The plate allows for growth of long bones throughout adolescence. 10\. realize also have hyaline cartilage in form of articular cartilage on epiphyseal surface 11\. epiphyseal line is just the plate calcifying → indicating the end of bone growth. **bone growth:** length vs. width (appositional). Controlled by growth hormone. [Length] 1. hyaline cartilage divides thus growth away from diaphysis 2. shaft calcifies by osteoblasts forming spongy bone. some of the bone is digested by osteoclasts, thus lengthening the medullary cavity 3. as bone lengthens, the epiphyseal plate maintains constant thickness by forming more as the cartilage is replaced by bone 4. once the bone reaches the final length, the epiphysial plate is calcified producing the epiphyseal line. [appositional]: occurs throughout life. 1. to keep proper proportions as bone lengthens 2. to handle mechanical stresses (increase body weight or exercise) thus increasing the diameter of the bone. 3. don't want bones too heavy thus once new bone is formed on the periosteal surface through action of osteoblasts, bone is broken down on the endosteal surface by action of osteoclasts. Part 8 ### types of fractures: 1. open/compound: bone is protruding out 2. closed/simple: bone isn't protruding out 3. comminuted: a. bone is broken in 3 or more places b. ex. Brittle bones associated with osteoporosis 4. spiral a. twisting force creates ragged break b. ex. Common sports injury 5. greenstick a. incomplete bone break in which one side breaks and the other bends. b. found more often in children. Why?? 6. Colles' fracture a. distal radius fracture b. occurs when falling and have outstretched hands 7. Impacted: bony fragments are pushed into each other 8. Pott's fracture: a. ankle injury b. typical of sports tackling. osteomyelitis: bone infection due to what type of fracture???