CO CO Materials Science & Fabrication Techniques

Question 1

Which thermoplastic material is most commonly used for high-temperature molding of AFOs due to its rigidity and durability?

Accepted Answer

Polypropylene

Answer

Polypropylene is the most widely used thermoplastic for rigid AFOs because it provides excellent structural rigidity, durability, and can be vacuum-formed at high temperatures.

Question 2

What is the primary purpose of using a cast sock when taking a plaster of Paris impression for a custom orthosis?

Accepted Answer

To provide a uniform interface and protect the skin during casting

Answer

A cast sock provides a smooth, uniform interface between the patient's skin and the plaster, protecting the skin and ensuring an accurate impression.

Question 3

Which property of carbon fiber makes it advantageous over polypropylene for energy-storing AFOs?

Accepted Answer

High stiffness-to-weight ratio with elastic energy return

Answer

Carbon fiber's high stiffness-to-weight ratio allows it to store and return elastic energy during gait, making it ideal for dynamic AFO designs.

Question 4

What does the term 'trim lines' refer to in orthotic fabrication?

Accepted Answer

The cut edges that define the extent and flexibility of a plastic orthosis

Answer

Trim lines are the cut edges of a plastic orthosis that determine its lateral and medial extent, directly controlling the device's flexibility and range of motion control.

Question 5

Low-density polyethylene (LDPE) is preferred over polypropylene for pediatric total contact insoles primarily because it:

Accepted Answer

Is softer and more flexible, accommodating a child's developing foot

Answer

LDPE is softer and more flexible than polypropylene, making it appropriate for pediatric insoles where gentle accommodation of a developing foot is required.

(CO) Certified Orthotics Specialist Practice Test

(CO) Certified Orthotics Specialist Practice Test

CO CO Materials Science & Fabrication Techniques