ANAPHY LEC

• Skeletal system


  • 206 bones in normal adult
  • 300 plus in children

  
• Functions of the skeletal system


  • Support
  • Protection
  • Movement
  • Storage
  • Blood cell production
• Major components of the skeletal system


  • Bone
  • Cartilage
  • Tendons
  • Ligament

  
• Bone cells


  • Osteoprogenitor
  • Osteoblast
  • Osteocytes
  • Osteoclasts

  
• Compact or dense bone


  • Dense and hard
  • Forms the protective exterior of all bones
  • Outer part of the bone

  
• Compact bone structure


  • Haversian system
  • Lacuna or lacunae
  • Lamellae or lamella
  • Canaliculi or canaliculus

  
• Spongy or cancellous bone


  • Found inside the compact bone
  • Very porous
  • Occurs in most bones
  • Haversian canal are much larger
  • Has fewer lamellae
  • Red bone marrow are present
  • Has trabeculae - spaces containing bone marrow and blood vessels

  
• Osteology


  The study of bone structure and treatment of bone disorder

  
• Bone ossification (osteogenesis)


  1. Intramembranous ossification

  2. Endochondral ossification

  
• Steps in intramembranous ossification


  1. Ossification center appears in the fibrous connective tissue membrane

  2. Bone matrix (osteoid) is secreted within the fibrous membrane

  3. Woven bone and periosteum form

  4. Bone collar of the compact bone forms and red marrow appears

  
• Appositional growth


  Formation of new bone on the surface of existing bone

  
• Endochondral growth


  Growth of cartilage in the epiphyseal plate and its eventual replacement by bone
• Bone remodeling

  1. Resorption-during which osteoclast digest old bone

  2. Reversal-when mononuclear cells appear on the bone surface

  3. Formation- when osteoblasts lay down new bone until the resorbed bone is completely replaced
• Bone repair (healing)


  Process in which a bone repairs itself following a bone fracture

  
• Bone and calcium homeostasis


  • Bone serves as the major storage site for calcium
  • Movement of calcium in and out of bone helps determine blood calcium levels
  • Calcium homeostasis is maintained by parathyroid hormone and calcitonin

  
• Bone and joint disorders

  • Achondroplasia
  • Osteogenesis imperfecta
  • Rickets
  • Osteomalacia
  • Osteoporosis

  
• Osteoclast


  Breaks down bone
• Calcium Homeostasis


  • Maintained by parathyroid hormone and calcitonin

  
• Achondroplasia


  • A form of short-limbed dwarfism
  • Literally means "without cartilage formation"
  • The problem is not in forming cartilage but in converting it to bone
  • Problem in the elongation of the limbs
• Osteogenesis Imperfecta


  • Also known as brittle bone disease
  • A genetic disorder that results from a lack of protein collagen producing very brittle bones that are easily fractured
  • Hump Formation
• Rickets


  • Bones of children are inadequately mineralized causing softened, weakened bones
  • Bowed legs and deformities of the pelvis, skull, and rib cage are common
  • Caused by insufficient calcium in the diet, or by vitamin D deficiency
• Osteomalacia


  • Bones are inadequately mineralized causing softened, weakened bones
  • Main symptom is pain when weight is put on the affected bone
  • Caused by insufficient calcium in the diet, or by vitamin D deficiency
• Osteomyelitis


  • Infection in bone caused by staphylococcus bacteria
  • The bacteria can enter a bone by: the bloodstream, injuries, and surgery
• Osteoporosis


  • Group of disease in which bone reabsorption outpaces bone deposit
  • Spongy bone of the spine is most vulnerable
  • Occurs most often in postmenopausal women
  • Bones become so fragile that sneezing or stepping off a curb can cause fracture
  • Age related
• Scoliosis


  • Lateral curvature of the central part of the spine
  • Posture problem
  • The condition can be brought on by:
  • Congenitally malformed vertebra
  • Chronic Sciatica
  • Paralysis of muscles on one side of the backbone
  • Poor posture

  
• Fracture


  • Break in a bone
  • Common types: simple compound, compression, comminuted and greenstick
  • Comminuted - bone breaks into many fragments. Common in the aged
  • Compressed - bone is crushed. Common in porous bones
  • Depressed - a broken bone portion is pressed inward. Typical of skull fracture
  • Impacted - broken bones ends are forced into each other. Commonly occurs when one attempts to break a fall with outstretched arms
  • Spiral - ragged break occurs when excessive twisting forces are applied to a bone. common sports failure
  • Greenstick - bone breaks incompletely much in the way a green adult. Common in children whose bones are more flexible
• Arthritis

  • It literally means “joint inflammation”, however some forms could affect the skin and internal organs
  • It is marked by pain, stiffness and swelling of the affected joints
  • It may include one or several joints
• Osteoarthritis


  • Commonly known as "wear and tear" arthritis
  • A degenerative joint disease in which the cartilage that covers the ends of the bones in the joint deteriorates
  • Symptoms include: pain, restriction of movement, formation of hard nobs
• Rheumatoid arthritis


  • An active chronic inflammatory autoimmune disease affecting synovial membrane
  • It involves the inflammation of joints
• Gouty arthritis


  • A disease associated with an inborn error of uric acid metabolism
  • Drinking alcoholic drinks and foods that is rich in uric acid
  • Male are prone to gouty arthritis
• Bursitis


  • An acute or chronic inflammation of the bursa (a small sac filled with fluid and located at friction points)
  • Common location are shoulder, elbow and hip area
• Articulation or joint


  • Physical connection between two bones
  • Holds bones together
  • Allows movement
  • Makes bone growth possible
• Arthrology


  The science that deals with the study of joints
• Functional classification of joints


  • Synarthrosis - immovable joint (ex. Skull)
  • Amphiarthrosis - slightly movable joint (ex. Between vertebrae)
  • Diarthrosis - freely movable joint (ex. Knee, elbow, wrist)
• Structural classification of joints

  • Fibrous Joints
  • Cartilaginous Joints
  • Synovial Joints
• Fibrous Joints


  • Bones are united by fibrous connective tissue
  • Allow little or no movement
  • Sutures - fibrous joints between the bones of the skull, immovable due to interlocking junctions between the bones and short numerous connective fibers
  • Syndesmosis - fibrous joints where the bones are separated by some distance and are held together by ligaments
  • Gomophoses - consist of pegs fitted into sockets and held in place by ligaments

  
• Cartilaginous Joints


  • Unite two bones by means of cartilage
  • Synchondrosis - bones are joined together by hyaline cartilage
  • Symphysis - bones are joined together by fibrocartilage

  
• Synovial Joints


  • Commonly referred to as freely movable joints, however their flexibility does vary
  • All synovial joints have certain characteristics in common
• Types of Synovial Joints


  • Plane or Gliding Joint
  • Saddle Joints
  • Hinge Joints
  • Pivot Joints
  • Ball and Socket Joints
  • Ellipsoid or Condyloid
• Plane or Gliding Joint


  • Consist of two opposed flat surfaces that glide over each other
  • Ex. Between two carpal bones, articular processes between vertebra