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Flashcards in Orthoses Deck (31)
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1
Q

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

A

STJ neutral, MTJ pronated, ankle dorsiflexed

2
Q

How can orthoses be classified?

A

based on MOA, manufacturer, or material

3
Q

what is the most accurate method of classifying orthoses?

A

MOA

4
Q

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

A

classifying based on materials

5
Q

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

A
  • functional (aka root, neutral)

- accommodative

6
Q

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

A

accommodative

7
Q

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

A

functional

8
Q

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

A

functional

9
Q

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?

A

accommodative

10
Q

Which type of orthotic alters function of the foot?

A

functional

11
Q

which is the thinnest rigid material?

A

graphite

12
Q

what is the single most important step of orthosis fabrication?

A

casting of the foot

13
Q

what is a negative cast?

A

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

14
Q

what is the positive cast?

A

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

15
Q

what are the 3 most common casting techniques?

A

neutral
partial weight bearing
computerized

16
Q

casting a functional orthotic uses what kind of casting technique?

A

neutral casting technique

17
Q

casting an accommodative orthotic uses what kind of casting technique?

A

partial weight-bearing casting technique

18
Q

What type of modifications are made to the positive mold?

A

intrinsic modification

19
Q

What types of modifications are made to the orthotic itself?

A

extrinsic modification

20
Q

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

A

extrinsic modification

21
Q

What does CAD/CAM scan?

A

scans negative cast or the foot driectly

22
Q

Where does a functional orthotic design end?

A

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

23
Q

where does an accommodative orthoses end?

A

is full length and full width

24
Q

which material is closed cell?

A

spenco

25
Q

which material is open cell?

A

poron or PPT

26
Q

What is “open cell”?

A

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

27
Q

what is “closed cell”?

A

made of discrete cells thru which gases do not pass freely

28
Q

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

A

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

29
Q

What is the mechanical objective of a functional orthotic?

A
  • resists GRF that cause abnormal motion to occur during STANCE PHASE
  • makes foot stable at push off
  • controls hypermobility of joints
30
Q

what are the uses of an accommodative orthotic?

A
  • relieve high pressure areas
  • accommodate plantar lesions
  • reduces shock, limits shear forces
31
Q

an accommodative orthotic is used in what type of feet?

A

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