Notes

Question 1

Musculoskeletal System consists of

Answer 1

• bones
• joints
• muscles

Question 2

Musculoskeletal System needed for

Answer 2

• for support to stand erect
• movement
• encase and protect the inner vital organs
• produce red blood cells, white blood cells, and platelets in the bone marrow (hematopoiesis)
• a reservoir for storage of essential minerals (calcium and phosphorus)

Question 3

Components of the musculoskeletal system

Answer 3

• Skeleton - bony framework of the body
• Bones and cartilage (forms of connective tissue)
• Joint (articulation)

Question 4

Bones

Answer 4

• hard, rigid, and very dense
• cells continuously turn over and remodel
• 206 bones

Question 5

Joints

Answer 5

• place of union of 2-or more bones
• functional units of the musculoskeletal system
• permit mobility for ADLs
• Fibrous, Cartilaginous, and Synovial joints

Question 6

Fibrous joints

Answer 6

• bones are united by interjacent fibrous tissue or cartilage
• immovable joints (sutures in the skull)

Question 7

Cartilaginous joints

Answer 7

• separated by fibrocartilagenous discs

- Slightly moveable (vertebrae)

Question 8

Synovial joints

Answer 8

• freely movable

- bones are separated and enclosed in a joint cavity

Question 9

Joint cavity

Answer 9

• lined with a synovial membrane that secretes lubricant/synovial fluid
• Fluid allows sliding of opposing surfaces and permits movement
• ## cartilage covers the surface of opposing bones

Question 10

Cartilage

Answer 10

• avascular
• receives nourishment from synovial fluid
• stable connective tissue (slow cell turnover)
• tough and flexible

Question 11

Ligaments

Answer 11

• fibrous bands that connect two bones
• strengthens the joint
  prevents movement in undesirable directions

Question 12

Bursa

Answer 12

• a sac filled with viscous synovial fluid
• located in areas of potential friction
• help muscles and tendons glide smoothly over the bone

Question 13

Muscles

Answer 13

• account for 40-50% of body weight
• contraction produce movement
• 3 types (skeletal, smooth, cardiac)

Question 14

Skeletal Muscle

Answer 14

• Voluntary muscles under conscious control
• composed of bundles of fasciculi (fibers)
• attach to bone by tendon (fibrous cord)

Question 15

Skeletal muscle movements

Answer 15

• Flexion, extension
• Abduction, adduction
• Pronation, supination
• Circumduction, rotation
• Inversion, eversion
• Protraction, retraction
• Elevation, depression

Question 16

Temporomandibular Joint (TMJ)

Answer 16

• articulation of the mandible and temporal bone
• palpate it in the depression anterior to the tragus of the ear
• permits jaw function for speaking and chewing
• 3 movements
  1) hinge action - open and close
  2) gliding - protrusion and retraction
  3) gliding from side-to-side movement of the lower jaw

Question 17

Spine

Answer 17

• 33 connecting bones (vertically stacked)
• Palpate spinous processes in furrow midline of back
• 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 3-4 coccygeal vertebrae
• Lateral view (a double S-shape)
• Movement
  1 - Flexion - bending forward
  2 - Extension - bending backward
  3 - abduction - lateral (side)
  4 - Rotation

Question 18

S-shape

Answer 18

• Cervical and lumbar curves are concave (inwards or anterior)
• thoracic and sacrococcygeal curves as convex
• allows the spine to absorb a great deal of shock

Question 19

Intervertebral disc

Answer 19

• elastic fibrocartilaginous plates between vertebrae

Question 20

Nucleus pulposus

Answer 20

• soft, semifluid, mucoid material

- cushion the spine (absorb and allows compression

Question 21

Shoulder

Answer 21

• belt of three large bones (humerus, scapula, clavicle), joint, and muscles
• glenohumeral joint (scapula and humerus at glenoid fossa)
• Ball and socket joint
• Rotator cuff (stabilize shoulder joint)

Question 22

Rotator Cuff

Answer 22

- Foarurs muscles (SITS)
1 - Supraspinatus 
2 - Infraspinatus
3 - Teres minor
4 - Subscapularis

Question 23

Shoulder Palpation landmark

Answer 23

• Acromion process
• Greater tubercle - humerus
• Coracoid process

Question 24

Wrist and Carpals

Answer 24

• half of 206 bones are in hands and feet
• Radiocarpal joint: the articulation of the distal radius (thumbs side) and 8 carpal bones
• Midcarpal: articulation between the two parallel rows of carpal bones. Allows flexion, extension, and rotation
• Metacarpophalangeal (MCP) and interphalangeal joints (DIP and PIP) permit finger flexion and extension.

Question 25

Elbow

Answer 25

• contains three bony articulation (humerus, radius, ulna)
• Hinge joint (flexion and extension)
• Muscles (biceps, brachioradialis, triceps, brachialis)
• Palpable - medial and lateral epicondyles of humerus, olecranon process of ulna
• Radioulnar joint: pronation and supination

Question 26

Hip

Answer 26

• articulation between acetabulum and head of the femur
• ball-and-socket joint
• Palpable (iliac crest, ischial tuberosity, greater trochanter of the femur)

Question 27

Knee

Answer 27

• articulation of three bones (femur, tibia, patella)
• the largest joint in the body (hinge joint - Flexion and extension)
• Palpable (tibial tuberosity, patella)

Question 28

Ankle and foot

Answer 28

• also known tibiotalar joint
• articulation of tibia, fibula, and talus
• Hinge joint (dorsiflexion, plantar flexion
• Palpable ( medial and lateral malleolus, calcaneus)
• Subtalar joint - allows inversion and eversion

Question 29

Infants and Children

Answer 29

• by 3 months gestation (scale model - skeleton made of cartilage)
• In utero - cartilage ossifies into the true bone and starts to grow
• long bones grow in 2 dimensions (width and lengthening)
• lengthening occurs at epiphyses (growth plate)
• the last closure of the growth plate is at 20 years.
• at birth, spine has a single C-shape

Question 30

The Pregnant Woman

Answer 30

• Increased levels of circulating hormones causes increase joint mobility
• Marternal postures (lordosis) - compensating for enlarging fetus - shifting weight backwards
• Nerve pressure creates aching, numbness, and weakness in upper extremities in some women

Question 31

The Aging Adult

Answer 31

• peak bone mass or bone mineral density (BMD) is reached in the early to late 20s with females reaching peaks earlier than males.
• Remodeling - cyclic process of bones resorption and deposition for maintaining sites that need repair
• postural changes are evident
• Long bones do not shorten with age
• decreased height of 3-5cm due to the shortening of the vertebral column (loss of water content and thinning of the intervertebral discs.
• ## A greater decrease in height occurs between 70-80s

Question 32

Osteoporosis

Answer 32

• Loss of bone matrix occurs rapidly
• loss of mineralized bone mass and leading to the porous bone thus the risk of fractures
• Aging women at greater risk than women
• caused by decreasing levels of estrogen in both sexes
  Prevention - resistance and weight training may increase bone density.