Skeletal System

Question 1

Function of Skeletal System

Answer 1

structural support, protection of vital organs, mechanism for movement, storage of vital minerals, source of blood cells.

Question 2

Bone Shapes

Answer 2

Flat, irregular, short, long, sesamoid

Question 3

Trabecular Bone

Answer 3

(aka cancellous bone, spongy bone)
network of bone tissue and marrow, strength for tensile and compressive biomechanical forces

Question 4

Cortical Bone

Answer 4

more dense network of bone tissue that typically forms the hard outer surface

Question 5

Osteoblasts

Answer 5

bone deposition

Question 6

Osteocytes

Answer 6

calcified osteoblasts, bone material

Question 7

Osteoclasts

Answer 7

bone resorption

Question 8

Matrix Composition

Answer 8

collagenous, non collagenous proteins, inorganic mineral salts, osteoblasts, osteoclasts, osteocytes

Question 9

Fractures, types

Answer 9

Closed, open, transverse, spiral, comminuted, impacted, greenstick, oblique

Question 10

Inflammatory phase

Answer 10

immediate onset, 3-5 days. bleeding in local area results in hematoma. hematoma provides the structural stability for new bone formation.

Question 11

Proliferative, (reparative) phase

Answer 11

early onset (first few days of injury), peaks 7-10, lasts 2-6 weeks. hematoma are replaced by fibrous tissue and osteoblasts begin laying down a soft internal callus. Not yet ready for loading.

Question 12

Remodeling (maturation) phase

Answer 12

begins around the 3rd week, peaking around 6-8 weeks, lasts 6-24 months. Osteoclasts resorb some external callous. Can sustain biomechanical load.

Question 13

Healing risk factors

Answer 13

Movement during bone healing phase
Poor circulation, smoking, metabolic disorders
Medications: corticosteroids, immunosuppressants
Advanced age
Poor nutrition, lacking calcium and vit D

Question 14

OT Implications: Imflammatory and Proliferative Phase

Answer 14

splint, immobilize

interventions focused on modify/adapt toward occupations and activities

“revise the current context or activity demands to support OT performance in natural setting”

Question 15

OT Implications: Remodeling Phase

Answer 15

Restore a skill or ability that has been impaired
Stretching, strengthening program restore neuromuscular functions

Question 16

Wolf’s Law

Answer 16

a bone will adapt (remodel) according to the bio-mechanical load placed on it.

Question 17

Osteoporosis

Answer 17

Trabecular bone is resorbed faster than it is remodeled, resulting in decrease in bone density

Question 18

Osteoporosis: Risk Factors

Answer 18

Reduction of estrogen in post-menopausal woman
Family history (genetics)
Personal history of falls
Long-term enforced bedrest
Low activity levels
Malnutrition (lack of CA and D)
High alcohol intake
Smoking

Question 19

Joints

Answer 19

Where two or more bones articulate to produce movement

Question 20

Fibrous joints

Answer 20

fibrous connective tissue
no movement between articular surfaces
e.g. coronal suture, interosseous membranes

Question 21

Cartilaginous Joints

Answer 21

variable amounts of fibrous connective tissue
little movement
e.g. costosternal joint, symphysis pubis

Question 22

Synovial Joints

Answer 22

1. fibrous articular capsule
2. synovial membrane
3. joint cavity/ space
4. synovial fluid
5. articular cartilage

Question 23

Uniaxial joints

Answer 23

one degree of freedom (1 df)

1. hinge joints (flx/ext)
2. pivot joints (rotation)
   e. g. interphalangeal joints

Question 24

Biaxial joints

Answer 24

two degrees of freedom (2 df)

1. saddle joints (flx/ext, abd/add) each articular surface is both convex and concave
   e. g. sternoclavicular
2. condyloid joints (flx/ext, abd/add) convex surface, concave surface
   e. g. metacarpophalangeal, atlantooccipital, scapulothoracic

Question 25

Multiaxial joints

Answer 25

three degrees of freedom (3 df)

1. ball and socket joints (infinite number of complex movements) most mobile, least stable
   e. g. glenohumeral joint, pelvifemorad joint
2. plane joints (infinite number)
   e. g. intercarpal joints