PROSTHETIC CPM COMPREHENSIVE EXAM
QUESTIONS AND SOLUTIONS STUDY GUIDE
●● What are the advantages to a TSB style socket
Answer: Equal distribution of pressure over entire limb, use of liner to
reduce shear forces and skin irritation, decreased pistoning
●● What are the disadvantages to a PTB style socket?
Answer: Concentrated pressures on select few areas, high pressure on
patellar tendon
●● What are the disadvantages to a TSB style socket
Answer: Requires the use of liners patient must be able to don liner, lack
of rotational control
●● What are the advantages to locking liner suspension
Answer: Auditory confirmation of lock increase confidence, can have
patient start to don and engage lock while seated, easy to manage
volume with socks
●● What are the disadvantages to a locking liner suspension
Answer: Pistoning/milking of the limb, can be difficult for patient to
align pin and lock must be consistent, lack of a rotational control
, ●● What are the advantages to a cushion liner/sleeve suspension
Answer: Reduced pistoning of prosthesis, easy volume management,
secure suspension, benefits of liner
●● What are the disadvantages to a cushion liner/sleeve susupension
Answer: Increased bulk around the knee that can reduce knee flexion,
can be hot (extra layer), requires dexterity to use liner
●● What are the advantages to a seal in system for suspension
Answer: Decreased pistoning, increased proprioception, decreased
apparent weight of prosthesis
●● What are the disadvantages to a a seal in system for suspension?
Answer: More difficult to control volume with socks, must have good
balance to don prosthesis, requires exact fit
●● What are the advantages to an elevated vacuum system
Answer: Promotes limb health, decreases pistoning, increased
proprioception, decreased sweating, decreased apparent weight
●● What are the disadvantages to elevated vacuum
Answer: Can cause damage to limb if fit is not appropriate, requires
exact fit, bulky and increased weight, expensive
QUESTIONS AND SOLUTIONS STUDY GUIDE
●● What are the advantages to a TSB style socket
Answer: Equal distribution of pressure over entire limb, use of liner to
reduce shear forces and skin irritation, decreased pistoning
●● What are the disadvantages to a PTB style socket?
Answer: Concentrated pressures on select few areas, high pressure on
patellar tendon
●● What are the disadvantages to a TSB style socket
Answer: Requires the use of liners patient must be able to don liner, lack
of rotational control
●● What are the advantages to locking liner suspension
Answer: Auditory confirmation of lock increase confidence, can have
patient start to don and engage lock while seated, easy to manage
volume with socks
●● What are the disadvantages to a locking liner suspension
Answer: Pistoning/milking of the limb, can be difficult for patient to
align pin and lock must be consistent, lack of a rotational control
, ●● What are the advantages to a cushion liner/sleeve suspension
Answer: Reduced pistoning of prosthesis, easy volume management,
secure suspension, benefits of liner
●● What are the disadvantages to a cushion liner/sleeve susupension
Answer: Increased bulk around the knee that can reduce knee flexion,
can be hot (extra layer), requires dexterity to use liner
●● What are the advantages to a seal in system for suspension
Answer: Decreased pistoning, increased proprioception, decreased
apparent weight of prosthesis
●● What are the disadvantages to a a seal in system for suspension?
Answer: More difficult to control volume with socks, must have good
balance to don prosthesis, requires exact fit
●● What are the advantages to an elevated vacuum system
Answer: Promotes limb health, decreases pistoning, increased
proprioception, decreased sweating, decreased apparent weight
●● What are the disadvantages to elevated vacuum
Answer: Can cause damage to limb if fit is not appropriate, requires
exact fit, bulky and increased weight, expensive
