MSK System

Cylindric with rounded ends, Often bear weight, (ex. femur)

small, bear little or no weight, (ex. phalanges)

protect vital organs, often contain blood-forming cells, (ex. scapula)

unique shapes, (ex. carpal bones of wrist, small bones of inner ear)

least common type, develops within a tendon, (ex. patella)

outer layer of bone; dense, compact bone tissue

inner layer of bone; spongy, cancellous trabecular tissue

the shaft (elongated cylindrical portion) between the ends of a long bone

the two knoblike ends of a long bone

complex canal network containing microscopic blood vessels that supply nutrients and oxygen to bone and lacunae; canals run vertically within the hard, cortical bone tissue

small cavities that house osteocytes (bone cells)

the softer tissue inside bones that contains large spaces (trabeculae) that are filled with red and yellow marrow

production of blood cells; occurs in red marrow of bones

connect bone marrow vessels with the haversian system and periosteum

• bone-forming cells (type of osteogenic cell)
• synthesize and lay down new bone, then attract Ca and phosphates to strengthen bone

• bone-destroying cells (type of osteogenic cell)
• resorb bone in the constant process of bone formation and brkdwn

special osteoblasts that sense and responsd to bone pressure and bending in order to direct the process of bone remodeling

collagen, mucopolysaccharides, lipids; deposits of inorganic calcium salts (carbonate & phosphate) provide hardness of bone

• very vascular tissue
• blood flow 200-400 mL/min
• has a main nutrient artery, branches into ascending/descending vessels, supplies cortex/marrow/haversian system
• few nerve fibers
• Sympathetic Nerve Fibers: dilation of blood vessels
• Sensory Nerve Fibers: pain signals

• Framework: allows body to be weight-bearing, upright
• Support Surrounding Tissues: (ex. muscle, tendon)
• Assists in Movement: thru muscle attachment, joint formation
• Protects Vital Organs: (ex. heart, lungs)
• Makes Blood Cells: in red bone marrow Stores Mineral Salts: (ex. calcium, phosphorous)

loss of bone minerals and density; release of free calcium from bone storage sites directly into the ECF

produced by thyroid gland, decreases serum Ca concentration, inhibits bone resorption, increases renal excretion of Ca and PO as needed to maintain balance

produced in body, transported in blood; promotes absorption of Ca and PO from small intestine; enhance PTH activity to release calcium from bone; deficiency can cause osteomalacia (softening of bone)

• (feedback loop system)
• Low Serum Calcium:
• ↑secretion, stimulates bone to promote osteoclastic activity, release Ca into blood
• ↓ renal excretion of Ca, facilitates absorption from intestine
• High Serum Calcium:
• ↓ secretion to preserve bone Ca supply

• secreted by anterior lobe of pituitary gland; increases bone length, determines amt of bone matrix before puberty
• Childhood Increase: gigantism
• Childhood Decrease: dwarfism
• Adult Increase: acromegaly (bone & soft tissue deformities)

regulate protein metabolism; ↑ or ↓ catabolism to reduce or intensify the organic matrix of bone; aid regulation of intestinal Ca/PO absorption

• Synarthrodial: completely immovable [ex. in the cranium]
• Ampiarthrodial: slightly movable [ex. in the pelvis]
• Diarthrodial (Synovial): freely movable [ex. elbow & knee]

• most common type in body; most commonly affected by disease; lined with synovium [membrane secretes fluid for lubrication & shock absorption] Ball-and-Socket: [shoulder, hip] movement in any direction
• Hinge: [elbow] motion in one plane, flexion, extension
• Condylar: [knee] flexion, extension, rotates slightly
• Biaxial: [wrist] gliding movement
• Pivot: [radioulnar] rotation only

small sacs lined w/synovial membrane, located at joints & bony prominences, prevent friction btwn bone & surrounding structures

• Smooth: non-striated, involuntary, autonomic nervous system, contracts organs & blood vessels
• Cardiac: short-fibered, striated, involuntary, autonomic nervous system Skeletal: striated, special-function, voluntary, central & peripheral NS, fxn is movement

junction of a peripheral motor nerve and the muscle cells that it supplies

dense, fibrous tissue that surrounds the entire muscle; contains the muscle's blood, lymph, and nerve supply

• Tendons: bands of tough, fibrous tissue that attach muscles to bones
• Ligaments: attach bones to other bones at joints

• Osteopenia: decreased bone density (bone loss), osteoporosis is severe osteopenia
• Synovial Joint Cartilage: less elastic and compressible, damaged cartilage leads to OA
• Muscle Tissue Atrophy: decreased coordination, loss of muscle strength, gait changes, risk for falls w/injury

• Traumatic Injury, Sports Activity
• Previous/Current Illness or Disease
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• Lifestyle
• Occupation
• Allergies
• Drug Use
• Herbs, Vit&Min Suppl, Biologic Compounds
• Food Intake
• Family Hx
• Current Health Problems