PATHOPHYSIOLOGY--NU545--UNIT 6-- MUSCULOSKELETAL EXAM QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS GRADED A++

PATHOPHYSIOLOGY--NU545--UNIT 6-- MUSCULOSKELETAL EXAM QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS GRADED A++ Bone matrix Collagen fibers, proteoglycnas, BMPs, BMP-2, BMP-6, and BMP-9. Glycoproteins Sialoprotein, osteocalcin, laminin, osteonectin, albumin, alpha-glycoprotein, minerals (elements) calcium and phosphate Compact bone (cortical bone) Makes up approx. 85% of the skeleton; present in every bone; highly organized, solid, and extremely strong--basic structural unit is Haversian system. Spongy bone (cancellous bone) Makes up approx. 15% of the skeleton; present in every bone; -less complex and lacks haversian systems -the lamellae are not arranged in concentric layers but in plates or bar termed trabeculae that branch and unite with one another to form an irregular meshwork -spaces b/w the trabeculae are filled with red bone marrow. Periosteum All bones are covered with a double-layered connective tissue. Sharpey Fibers Collagenous fibers that penetrate the bone and help hold or attach tendons and ligaments to the periosteum. Diaphysis Narrow tubular midportion of a long bone. Metaphysis Broader neck of a long bone. Epiphysis The broad end of a long bone. Endosteum Lines the outer surfaces of both types of marrow cavity. Flat bones (Ribs or scapulae) 2 plates of compact bone which are roughly parallel to each other; b/w the compact bone plates is a layer of spongy bone. Short bones (Cuboidal bones) (wrist or ankle) often cuboidal in shape; consist of spongy bone covered by a thin layer of compact bone. Irregular bones (Vertebrae, mandibles, other facial bones) have various shapes that include thin and thick segments; thin part of an irregular bone consists of 2 plates of compact bone with spongy bone b/w the plates; thick part consists of spongy bone surrounded by later of compact bone. Physeal closure When the skeleton is mature, the epiphyseal plate is replaced by bone. It unites the metaphysis and epiphysis. It occurs earlier in girls than boys. Duchenne muscular dystrophy a type of disorder that causes degeneration of skeletal muscle fibers. The most common of the muscular dystrophies; Described by Duchenne as a pseudohypertrophic muscular paralysis associated with large amounts of fat and connective tissue. Classic Duchenne MD occurs in boys only and has a history of x-linked inheritance in half of the cases. Osteogenesis imperfecta (OI) (Brittle bone disease) a genetic disorder of connective tissues that affects primarily bone, usually autosomal dominant but can be autosomal recessive. Major errors in lie in the synthesis of collagen. The gene responsible for the encoding of collagen easily mutates. Osteoarthritis