Exam 5: Prosthetics TransTib ReadGuide/Lecture/Chart, Suspension Flashcards Preview

Bringman class fall 2015 > Exam 5: Prosthetics TransTib ReadGuide/Lecture/Chart, Suspension > Flashcards

Flashcards in Exam 5: Prosthetics TransTib ReadGuide/Lecture/Chart, Suspension Deck (71):
1

What is the main goal of any type of suspension?

(3 points)

 

 

  • suspension is the method by which the prosthesis is held to the limb
  • Keep the limb in contact with the prosthesis
  • When prosthesis  is suspended perfectly, there is no relative motion between the socket and limb. When motion occurs because of a faulty or inadequate suspension system, the limb is subjected to pistoning.

2

What is a Waist Belt suspension?

What is it: connected by an elastic strap to the thigh corset (or other socket I think); encircle the pelvis between the iliac crest and the greater  trochanters; have adjustable belts with buckles and an inverted Y-strap that is attached to the socket; have an elastic component to  accommodate for motion at hip and knee

 

**older, less common

A image thumb
3

Waist Belt: Indications (2-3)

Indications: for early transtibial sockets; Good if large volume changes are expected.

May be used for an obese pt (class notes).

4

Waist Belt: Advantages (2)

Provides auxiliary suspension &  decreases pistoning

5

Waist Belt: Disadvantages (4)

  1. Cumbersome to don and doff;
  2. Poor cosmesis;
  3. tension must be had in order to prevent pistoning- tension decreases hip flexion- straps
  4. must be loosened in order to sit

6

Joint and corset: What is it?

What is it: skillfully molded corset that can gain purchase over the smaller circumference of the thigh (just proximal to the knee joint); stiff leather corset- straps or laces that can be tightened as the prosthesis is donned.

Transfers some weight bearing to the thigh.

Includes a metal knee joint that can help with mediaolateral stability of the knee.

*Rarely used anymore

**older, less common

A image thumb
7

Joint and corset: Indications (2)

Indications: 

  • Good for short Residual Limb
  • good for ligamentous instability in the knee

**rarely used anymore.

8

Joint and corset: Advantages (2)

  1. is somewhat load bearing.
  2. Provides ML knee stability (“may be the suspension of choice for ligamentous instability in the knee”)

9

Joint and corset: Disadvantages (2)

  1. Hot Initially;
  2. Poor Cosmesis

10

Cuff Strap: What is it?

 

**Also called supracondylar cuff

What it is: flexible leather cuff that attaches to the medial and lateral walls of the socket at the same point that orthotic knee joints would attach (just posterior and proximal to the anatomic knee center); has adjustable strap that completely encircles that thigh just proximal to the patella; the anatomical structures that provide suspension- patella and femoral condyles; for stronger hold- lower medial and lateral walls

 

**older, less common

A image thumb
11

Cuff Strap: Indications (1)

Indications:

  • Longer, traumatic residual limb

**Almost no one would get this anymore

(also called Supracondylar Strap)

12

Cuff Strap: Advantages (5)

Advantages:

  1. Simple,
  2. durable,
  3. Easy to don,
  4. Volume changes have less impact
  5. Does not get as hot as some of the others

**Almost no one would get this anymore

(also called Supracondylar Strap)

13

Cuff Strap: Disadvantages 4)

  1. Tight, not so appropriate in presence of marginal circulation;
  2. reduced medial and lateral stability- not good for person with instability or shorter limbs;
  3. may be a problem for persons with much muscle or adipose tissue around the lower thigh
  4. Doesn't look cool!

 

**Almost no one would get this anymore

(also called Supracondylar Strap)

14

List the transtibial suspension methods we discussed or are in the book: (10)

  1. Waste Belt
  2. Joint and Corset
  3. Cuff Strap (Supracondylar Cuff)
  4. Supracondylar
  5. Supracondylar Suprapatellar
  6. Sleeve
  7. Suction
  8. Locking Liners
  9. VASS (vacuume assisted socket suspension)
  10. Elevated Suction

15

Which suspension systems did Dr. Mincer say were "kinda old and less common" now? (5)

 

  1. Supracondylar
  2. Supracondylar strap (cuff strap)
  3. Supracondylar Suprapatellar
  4. Waist Strap
  5. Corset

**she said Sleeve Suspension was not so old, but I'm not sure if it qualifies as a newer suspension.

16

Which suspension systems did Dr. Mincer say were the "newer suspensions"? (4)

  1. Pin and Shuttle (a type of locking liner suspension)
  2. Suction
  3. Vacuum Assisted Socket Suspension (VASS)
  4. Sleeve?

**she said Sleeve Suspension was not so old, but I'm not sure if it qualifies as a "newer suspension."

17

Supracondylar suspension: what is it?

What is it: is achieved by incorporating the femoral condyles within the rigid transtibial socket; extends medial and lateral trim lines- makes medial-lateral  narrower at knee joint (prevents the knee joint from moving upward out of the socket by capturing the femoral condyles)

Points from class:

  • not the same as supracondylar strap
  • comes up above the condyles and indented in
  • A couple ways to do don:
    1. Use removable wall: put leg in socket with removable wall piece off, then put removalble wall peice on (See picture)

    2. Use soft socket: first don soft socket, then put soft socket with limb into the hard socket

(the one in the picture has a removable wall in order to be able to slide the condyles into the socket before replacing the removable part to lock over the condyles)

**older, less common

A image thumb
18

Supracondylar suspension: Indications (1)

  1. May require good dexterity, depending on specific model

A image thumb
19

Two ways to don a supracondylar suspension:

A couple ways to do don:

  1. Use removable wall: put leg in socket with removable wall piece off, then put removalble wall peice on (See picture)
  2. Use soft socket: first don soft socket, then put soft socket with limb into the hard socket

A image thumb
20

Supracondylar Suspension: Disadvantages (3)

  1. Doesn’t accommodate well to changing volume;
  2. difficult to don bc of the width of the proximal opening is smaller than the width of the condyles;
  3. can be apparent though clothes (cosmesis issue)

21

When referring to suspensions, SC stands for what?

supracondylar

(specifically a supracondylar suspension)

A image thumb
22

Supracondylar suspension: advantages (1)

  1. Minimizes vascular problems because it doesn’t have a cuff that goes all the way around thigh

**DOES NOT provide significant mediolateral stability (despite what pg 631 of the book says). Dr. Mincer was very clear about this in class.  It might provide a slight amount of mediolateral stability, but not enough to matter or for us to care about.

23

What is not an advantage of Supracondylar Suspension?

**DOES NOT provide significant mediolateral stability (despite what it says on pg 631 of book). Dr. Mincer was very clear about this in class.  It might provide a slight amount of mediolateral stability, but not enough to matter or for us to care about.

24

What is it called when supracondylar suspension is combined with a PTB-style socket?

PTB-SC socket

25

Supracondylar suprapatellar suspension: what is it?

It is like a PTB-SC socket with the trim line of the anterior aspect extended to the proximal surface of the patella.

Then it is called PTB-SCSP (patellar tendon-bearing supracondylar/suprapatellar); and allows the formation of a quadriceps bar above the patella that provides suspension and resists hyperextension

Basically like a supracondylar suspension that is extended to the superior part of the patella

**older, less common

 

A image thumb
26

What does PTB-SCSP stand for?

Patellar Tendon Bearing - Supracondylar Suprapatellar

Type of socket suspension

27

Supracondylar suprapatellar: indications (1)

Indications: not appropriate for heavy thighs

28

Supracondylar suprapatellar: advantages (2)

  • Minimizes vascular problems;
  • may provide some ML knee support (but not enough to really matter - Dr. Mincer)

29

Supracondylar Suprapatellar: Disadvantages (2)

 

  1. Difficult to kneel;
  2. Poor cosmesis in sitting (when knee is flexed)

 

30

Sleeve suspension: what is it?

What is it: provides suspension through 2 biomechanical principles- friction and vacuum (book says this but later says only friction); sleeve is approx 20 cm prox and distal to knee center and fitted over the proximal end of the prosthetic socket; should fit snugly without hindering circulation. Uses friction only to suspend prosthesis because they allow air to flow through them.

Materials:

  • Standard has been neoprene (like wet suit)
  • There are now some silicone sleeves (dr mincer)

**one of the most versatile means of suspending a prosthesis

***not in the old, uncommon category; not sure if it is "new" either

A image thumb
31

Sleeve Suspension: indications (2)

  1. Provides primary or auxiliary suspension;
  2. Requires good dexterity.

32

Sleeve Suspension: Advantages (3)

  1. Neoprene is light and useful for  dissipating perspiration;
  2. simple to don;
  3. decreased pistoning

33

Sleeve Suspension: Disadvantages (3)

  1. decreased durability;
  2. doesn’t provide knee stability (over time- can lead to skin breakdown and pain);
  3. no knee flexion beyond 100 degrees because the sleeve will bunch up

34

Suspensions: Suction vs Sleeve

suction is an actual gel to gel contact that makes a vacuum

sleeve is just on on the outside and uses friction not vacuum/suction

35

What is the max amount of sock ply you would want to use with a suction suspension?

Up to 5 ply

(try to minimize amount of ply because ply can compromise suction)

36

What is critical about socks when using a suction suspension?

The sock must not be too long!

The sock must come above the proximal trim line, but not much higher. The sock is ouside the gel liner but inside the hard socket and sleeve. The gel inside surface of the sleeve and the gel outside surface of the gel liner must touch to make a seal. If the sock is too long, it will prevent this.

A image thumb
37

Suction: what is it?

What is it: suction is created by sealing sleeves; these sleeves  are made from non-porous material that seals the proximal end of the socket against the skin so that no air can flow in or out of the socket (one way air valves are often used  to allow air that that is trapped during donning to escape); excellent with combined with TSB

 

***Dr. Mincer said it was not the same as VASS, but VASS was the only ting in her chart. So I am including what we came up with using the chart (for VASS) and book for now. I have emailed her to try to figure out how she wants us to handle this.

38

Suction/(chart VASS): Indications (2)

  1. Used in 75% of new amputees but need mature limb;
  2. skin must be free of deep scars or invagination that may allow air to pass through

39

Suction/(chart VASS): Advantages (4)

  1. Decreases daily volume fluctuations;
  2. One-way valve assist to maintain suction;
  3. very little pistoning;
  4. may provide a means for improving healthy circulation in the residual limb and controlling limb volume

40

What looks like an intersting place to visit in Romania?

Peles Castle

A image thumb
41

Suction/(chart VASS): Disadvantages (2)

Disadvantages: none listed in chart;

  1. have a high susceptible to failure due to leaks (even the smallest hole would allow air in);
  2. not very durable- easily replaced though

42

Locking liners (same as Pin/Shuttle or Lanyard in chart): what is it?

What is it: uses a roll-on silicon liner; held on by friction; has a threaded hole at the end of the distal end of the liner; hole serves as attachment point for suspension hardware; can attach using 3 methods

  1. ring (early models)
  2. strap (requires less precision)
  3. Pin-and lock (requires two hands to remove)

43

Locking Liner, ring method

  • describe it
  • Good for/Advantages
  • Problems

  • ring: early models used a ring that was screwed into the distal end of the liner; ring came through a special opening; can pass a thin bar through the ring.  
  • Good for individuals who are having problems doffing.
  • Problem- could lose the bar, need additional clearance under the limb  

(didn't find a picture)

44

Locking Liner, strap method

  • describe it
  • Good for/Advantages
  • Problems

  • strap: difficulties with the ring gave rise to the strap; strap manually fed through at the distal end of the socket and then secured to the outside of the socket; strap must be long enough.
  • Good- the limb will be secured in sleeve once the strap is tightened (don't have to be as worried about careful placement), requires less force to don, no additional clearance needed
  • There is a variant of this system that uses a lanyard and a spacial lock mechanism to secure the lanyard in the distal end of the socket. The lanyard is permanently attached to the locking mehcanisms so it needs to be disconnected from teh liner each time the liner is taken off

A image thumb
45

Locking Liner, pin-and-lock method

  • describe it
  • Good for/Advantages
  • Problems

  • pin-and-lock: pin can range from 3 to 10 cm in length; pin works with a locking mechanism;
  • pt can learn how many clicks are normal for them when donning
  • can be frustrating to try and align the pin and locking mechanism; need to be able to disengage pin while pushing the socket off with the other hand

A image thumb
46

Locking Liners: Indications (1)

Can be good for scarred or sensitive RL (residual limb)

47

Locking Liners: Advantages (1)

Advantages: Thick, cushioned interface between socket and RL

48

Locking Liners: Disadvantages (4)

Disadvantages:

  1. Hot so increased perspiration;
  2. increased cost;
  3. doesn’t provide knee stability;
  4. traction on skin.

49

What looks like a fun thing to visit in Aiken, SC?

Aiken Steeplechase (Spring or Fall)

(unless lots of people get hurt)

A image thumb
50

Waist Belt: Everything

Waist belt:  

  • What is it: connected by an elastic strap to the thigh corset; encircle the pelvis between the iliac crest and the greater  trochanters; have adjustable belts with buckles and an inverted Y-strap that is attached to the socket; have an elastic component to  accommodate for motion at hip and knee
  • Indications: for early transtibial sockets; Good if large volume changes are expected.
  • Advantages: Provides auxiliary suspension &  decreases pistoning
  • Disadvantages: Cumbersome to don and doff; Poor cosmesis; tension must be had in order to prevent pistoning- tension decreases hip flexion- straps must be loosened in order to sit

51

Joint and Corset: Everything

Joint and corset:

  • What is it: skillfully molded corset that can gain purchase over the smaller circumference of the thigh (just proximal to the knee joint); stiff leather corset- straps or laces that can be tighten as the prosthesis is donned.
  • Indications: rarely used anymore. Good for short Residual Limb
  • Advantages: Is somewhat load bearing. Provides ML knee stability “may be the suspension of choice for ligamentous instability in the knee”
  • Disadvantages: Hot Initially; Poor Cosmesis

52

Cuff Strap: Everything

Cuff strap: (also called supracondylar cuff)

  • What it is: flexible leather cuff that attaches to the medial and lateral walls of the socket at the same point that orthotic knee joints would attach (just posterior and proximal to the anatomic knee center); has adjustable strap that completely encircles that thigh just proximal to the patella; the anatomical structures that provide suspension- patella and femoral condyles; for stronger hold- lower medial and lateral walls
  • Indications: Longer, traumatic residual limb
  • Advantages: Simple, durable, Easy to don, Volume changes have less impact
  • Disadvantages: Tight, not so appropriate in presence of marginal circulation; reduced medial and lateral stability- not good for person with instability or shorter limbs; may be a problem for persons with much muscle or adipose tissue around the lower thigh

53

Supracondylar: Everything

Supracondylar:

  • What is it: is achieved by incorporating the femoral condyles within the rigid transtibial socket; extends medial and lateral trim lines- makes medial-lateral  narrower at knee joint (prevents the knee joint from moving upward out of the socket by capturing the femoral condyles)
  • Indications: May require good dexterity, depending on specific model
  • Advantages: minimizes vascular problems; adds significant medial-lateral stability (this came from the book pg 631 , but it is not in the chart; Dr. Mincer said supracondylar suspension assistance with ML stability is not significant)
  • Disadvantages: Doesn’t accommodate well to changing volume; difficult to don bc of the width of the proximal opening is smaller than the width of the condyles; can be apparent though clothes

54

Supracondylar Suprapatellar: Everything

Supracondylar suprapatellar:

  • What is it: PTB-SCSP (patellar tendon-bearing supracondylar/suprapatellar); allows the formation of a quadriceps bar above the patella that provides suspension and resists hyperextension
  • Indications: not appropriate for heavy thighs
  • Advantages: Minimizes vascular problems; provides some ML knee support
  • Disadvantages: Difficult to kneel; Poor cosmesis in sitting (when knee is flexed)

55

Sleeve (suspension): Everything

Sleeve:

  • What is it: provides suspension through 2 biomechanical principles- friction and vacuum; sleeve is approx 20 cm prox and distal to knee center and fitted over the proximal end of the prosthetic socket; should fit snugly without hindering circulation
  • Indications: Provides primary or auxiliary suspension; Requires good dexterity.
  • Advantages: Neoprene is light and useful for  dissipating perspiration; simple to don; decreased pistoning
  • Disadvantages: decreased durability; doesn’t provide knee stability (over time- can lead to skin breakdown and pain); no knee flexion beyond 100 degrees because the sleeve will bunch up

56

Suction: Everything

Suction: Dr. Mincer said not the same as VASS

  • What is it: suction is created by sealing sleeves; these sleeves  are made from non-porous material that seals the proximal end of the socket against the skin so that no air can flow in or out of the socket (one way air valves are often used  to allow air that that is trapped during donning to escape); excellent with combined with TSB
  • Indications: Used in 75% of new amputees but need mature limb; skin must be free of deep scars or invagination that may allow air to pass through
  • Advantages: Decreases daily volume fluctuations; One-way valve assist to maintain suction; very little pistoning; may provide a means for improving healthy circulation in the residual limb and controlling limb volume
  • Disadvantages: none listed in chart; have a high susceptible to failure due to leaks (even the smallest hole would allow air in); not very durable- easily replaced though

57

Locking LIners: Everything

Locking liners (same as Pin/Shuttle or Lanyard in chart?)

  • What is it: uses a roll-on silicon liner; held on by friction; has a threaded hole at the end of the distal end of the liner; hole serves as attachment point for suspension hardware; can attach using 3 methods
    1. ring: early models used a ring that was screwed into the distal end of the liner; ring came through a special opening; can pass a thin bar through the ring.  Good for individuals who are having problems doffing. Problem- could lose the bar, need additional clearance under the limb  
    2. strap: difficulties with the ring gave rise to the strap; strap manually fed through at the distal end of the socket and then secured to the outside of the socket; strap must be long enough. Good- the limb will be secured in sleeve once the strap is tightened (don't have to be as worried about careful placement), requires less force to don, no additional clearance needed
    3. pin-and-lock: pin can range from 3 to 10 cm in length; pin works with a locking mechanism; can be frustrating to try and align the pin and locking mechanism; need to be able to disengage pin while pushing the socket off with the other hand
  • Indications: Can be good for scarred or sensitive RL (residual limb)
  • Advantages: Thick, cushioned interface between socket and RL
  • Disadvantages: Hot so increased perspiration; increased cost; doesn’t provide knee stability; traction on skin.

58

What is alignment for a trans tib prosthesis? (quick definition)

* alignment refers to the spatial orientation of the prosthetic socket relative to the foot

59

What is alignment for a trans tib prosthesis?

Prosthetist stands prosthesis up on a table (bench) and looks at the alignment of the socket relative to the foot (and pilon)

bench alignment serves as the starting point for the dynamic alignment process

A image thumb
60

What is the standard bench alignment?

standard bench alignment has the socket in 5 degrees of flexion and 5 degrees of adduction while the top of the prosthetic foot is level in both the frontal and sagittal planes and the medial border of the foot is parallel to the line of progression

 

61

What is transtib socket flexion?

tilting the proximal end of the socket anteriorally (like how it would move in knee flexion)

A image thumb
62

what is transtib socket extension?

tilting the proximal part of the socket posteriorally (like how it would be in knee extension)

A image thumb
63

Where is a place I would want to take you if you came to Bend, OR

Lava River Cave

A image thumb
64

What is transtib socket abduction?

proximal socket moves medially (like if wearer had genu valgum)

A image thumb
65

what is transtib socket adduction?

proximal part of the socket tilts laterally (like if pt had genu varum)

A image thumb
66

During bench alignment, the knee is generally set in slight flexion. What is the main reason for this?

5 degrees of flexion: To elongate the quadriceps muscles slightly so that they are better prepared to accept the full weight of the body and to aid in shock absorption during loading response.

Gives mechanical advantage to quads

67

During bench alignment, the socket is generally set in slight adduction. What is the main reason for this?

5 degrees of adduction: ensured that the foot is sufficiently inset to create the appropriate varus moment during stance  

68

What is the main advantage of an exoskeletal prosthesis over an endoskeletal, and vice versa?

Endoskeletal

  • *the structure of the prosthesis is located deep inside the prosthetic limb
  • advantages:
    • adjustability;
      • allows for use of modular components that can be adjusted or replaced quickly and easily when needed. These components are not custom made.
    • realistic appearance
      • virtually any size and shape can be created by shaping soft lightweight foam over the components; can even have life-like details including moles, freckles, pores, and hair

Exoskeletal

  • the socket of an exoskeletal prosthesis is attached to the foot through an external composite  lamination that is custom shaped
  • Advantages:
    • durable & easily cleanable (non porous, chemically inert, and waterproof)
  • Disadvantages
    • heavier, custom made, less adjustable

 

69

Endoskeletal prosthesis

  • What is a big distinction from an exoskeletal prosthesis?
  • Advantages (2)
  • Disadvantages (2)

 

Endoskeletal

  • *the structure of the prosthesis is located deep inside the prosthetic limb
  • advantages:
    1. adjustability;
      • allows for use of modular components that can be adjusted or replaced quickly and easily when needed. These components are not custom made.
    2. realistic appearance
      • virtually any size and shape can be created by shaping soft lightweight foam over the components; can even have life-like details including moles, freckles, pores, and hair
  • Disadvantages
    1. not as durable
    2. not as easily cleanable (I am guessing)

70

Exoskeletal prosthesis

  • What is a big distinction from an endoskeletal prosthesis?
  • Advantages (2)
  • Disadvantages (4)

Exoskeletal

  • *the socket of an exoskeletal prosthesis is attached to the foot through an external composite  lamination that is custom shaped
  • Advantages
    1. durable &
    2. easily cleanable  (non porous, chemically inert, and waterproof)
  • Disadvantages
    1. heavier,
    2. custom made (expensive?)
    3. less adjustable
    4. less realistic appearance

71

T/F: almost all transtibial amputees now use a gel liner of soem sort

true (I think)

I have a note from Dr. Mincer: by default almost all transtibial amputees now use a gel liner of some sort (I think she meant at least eventually)