skeletal system

• Cardiovascular system


  Composed of 206 bones, along with cartilage, tendons, and ligaments, that make up the framework or skeleton of the body
• Parts of the skeleton

  • Axial skeleton (80 bones)
  • Appendicular skeleton (126 bones)

  
• Axial skeleton


  Consists of the skull, spine, ribs and sternum (thorax)

  
• Appendicular skeleton


  Consists of the shoulder or pectoral girdle, arms, hands, pelvic girdle, legs, and feet

  
• Bones are composed of about 50% water and 50% a solid, calcified, rigid substance known as osseous (AH see us) tissue

  
• Functions of bones

  • Provide shape, support, and the framework of the body
  • Protect internal organs
  • Serve as a storage place for minerals such as salts, calcium, and phosphorus
  • Play an important role in hematopoiesis (the formation of blood cells that takes place in bone marrow)
  • Provide a place to attach muscles
  • Make movement possible through articulation (manner in which the parts come together at a joint)
• Classifications of bones by shape

  • Long bones
  • Short bones
  • Flat bones
  • Irregular bones

  
• Long bones


  Include the femur (thigh), tibia (larger shin), fibula (smaller shin bone), humerus (upper arm), radius (larger forearm), and ulna (smaller forearm)

  
• Short bones


  Include the carpals of the wrist and tarsals of the ankle
• Flat bones

  Include the skull, sternum (breastbone), and scapula (shoulder bone)

  
• Irregular bones


  Include the vertebrae (spine), and pelvic

  
• Parts of a long bone

  • Epiphysis (growing end)
  • Diaphysis (shaft)
  • Periosteum (outside covering)
  • Medullary (inner space containing bone marrow)
  • Endosteum (lining of medullary cavity)

  
• Joint


  A place where two or more bones connect
• Types of joints


  • Synarthrosis (allows no movement, e.g. cranial suture)
  • Amphiarthrosis (allows slight movement, e.g. vertebra)
  • Diarthrosis (allows free movement in a variety of directions, e.g. knee, hip, elbow, wrist, and foot)
• Types of joint movements

  • Flexion (bending a limb)
  • Extension (straightening a flexed limb)
  • Abduction (moving a body part away from the middle)
  • Adduction (moving a body part toward the middle)
  • Circumduction (moving a body part in a circular motion)
  • Supination (lying supine or turning the palm or foot upward)
  • Pronation (lying prone or turning the palm downward)
  • Dorsiflexion (bending a body part backwards)
  • Protraction (moving a body forward)
  • Retraction (moving a body part backward)
  • Rotation (moving a body part around a central axis)
  • Inversion (turning inward)
  • Eversion (turning outward)
• Body positions


  • Lateral recumbent (lying on your left or right side)
  • Fowler's position (sitting straight up or reclining slightly; legs straight or bent)
  • Trendelenburg position (lying supine with head lower than feet)
• Vertebral column


  Composed of separate bones called vertebrae, connected to form four spinal curves

  
• Spinal curves


  • Cervical curve (first 7 vertebrae)
  • Thoracic curve (next 12 vertebrae)
  • Lumbar curve (5 vertebrae)
  • Sacral curve (sacrum and coccyx)
• Pelvis


  The lower portion of the trunk of the body, formed by the hip bones, sacrum, and coccyx
• Hip bones

  • Ilium
  • Pubis
  • Ischium
• Male pelvis


  Shaped like a funnel, heavier and stronger than the female pelvis
• Female pelvis


  Oval to round, wider than the male pelvis
• Osteoporosis


  Age-related loss of bone mass or density
• Bone remodeling

  1. Broken down by osteoclasts in a process called resorption

  2. Formed again by osteoblasts
• Bone formation and healing slow down as part of the aging process