Orthoses

Question 1

What is the correct placement of foot/ankle for neutral position casting?

Answer 1

STJ neutral, MTJ pronated, ankle dorsiflexed

Question 2

How can orthoses be classified?

Answer 2

based on MOA, manufacturer, or material

Question 3

what is the most accurate method of classifying orthoses?

Answer 3

MOA

Question 4

which method is inaccurate, unreliable, and inappropriate way to classify orthoses?

Answer 4

classifying based on materials

Question 5

when classifying orthoses based on MOA, what are the 2 subcategories?

Answer 5

• functional (aka root, neutral)

- accommodative

Question 6

Which type of orthoses does not attempt to control motion of STJ and MTJ?

Answer 6

accommodative

Question 7

which type of orthoses maintans normal foot function at STJ and MTJ?

Answer 7

functional

Question 8

Which type of orthotic greatly improves functioning of joints proximal and distal to the STJ and MTJ?

Answer 8

functional

Question 9

which type of orthotic provides comfort from plantar lesions and bony prominences rather than attempt to affect joints proximal and distal to STJ and MTJ?

Answer 9

accommodative

Question 10

Which type of orthotic alters function of the foot?

Answer 10

functional

Question 11

which is the thinnest rigid material?

Answer 11

graphite

Question 12

what is the single most important step of orthosis fabrication?

Answer 12

casting of the foot

Question 13

what is a negative cast?

Answer 13

the mold of the foot made from plaster or taken in foam material

Question 14

what is the positive cast?

Answer 14

made from plaster material poured into the negative cast or from laser scan

Question 15

what are the 3 most common casting techniques?

Answer 15

neutral
partial weight bearing
computerized

Question 16

casting a functional orthotic uses what kind of casting technique?

Answer 16

neutral casting technique

Question 17

casting an accommodative orthotic uses what kind of casting technique?

Answer 17

partial weight-bearing casting technique

Question 18

What type of modifications are made to the positive mold?

Answer 18

intrinsic modification

Question 19

What types of modifications are made to the orthotic itself?

Answer 19

extrinsic modification

Question 20

a rearfoot post is an example of what type of modification?

Answer 20

extrinsic modification

Question 21

What does CAD/CAM scan?

Answer 21

scans negative cast or the foot driectly

Question 22

Where does a functional orthotic design end?

Answer 22

ends behind metatarsal heads and just lateral to 1st met and just medial to 5th met (not full width)

Question 23

where does an accommodative orthoses end?

Answer 23

is full length and full width

Question 24

which material is closed cell?

Answer 24

spenco

Question 25

which material is open cell?

Answer 25

poron or PPT

Question 26

What is “open cell”?

Answer 26

ex. poron or PPT

an open cell material has open windows leaving many cells interconntected so that gas can pass from one cell to another

Question 27

what is “closed cell”?

Answer 27

made of discrete cells thru which gases do not pass freely

Question 28

what happens as the # of open cells decrease (becomes more “closed”)?

Answer 28

the ability of the material to withstand compression increases –> is more durable

Question 29

What is the mechanical objective of a functional orthotic?

Answer 29

• resists GRF that cause abnormal motion to occur during STANCE PHASE
• makes foot stable at push off
• controls hypermobility of joints

Question 30

what are the uses of an accommodative orthotic?

Answer 30

• relieve high pressure areas
• accommodate plantar lesions
• reduces shock, limits shear forces

Question 31

an accommodative orthotic is used in what type of feet?

Answer 31

neuropathic
vascularly impaired
arthritic
feet with inoeprable bony or soft tissue prominence