Prosthetic Prep Exam

Question 0

A below knee amputee is seen in your clinic and states he feels anterior/distal discomfort in his prosthetic socket. How would you address this problem?

Answer 0

Extend the prosthetic socket

Add pre-tibial pads to the prosthetic socket.

Question 1

The Ertl Procedure is known as an osteomyoplastic amputation reconstruction that performs a bridge between what?

Answer 1

Tibia and fibula.

Question 2

A below the knee amputee is seen in clinic and states he has posterior knee or hamstring discomfort. How would you address this problem?

Answer 2

Lower the posterior medial brim on the prosthetic socket.
Align prosthetic foot more posterior in relation to the prosthetic socket.
Extend the socket.

Question 3

Which level(s) of amputation may lead to an equinus gait deformity:

Answer 3

Lisfranc amputation
Chopart amputation
Transmetatarsal amputation.

Question 4

A below knee amputee presents wearing a PTB style endoskeletal prosthesis with general knee pain and distal end pressure. The patient doffs her prosthesis and liner, upon examination of her residual limb you note redness on the distal tibia and inferior aspect of the patella bone. What would be the most logical clinical action(s) you could take at this point in addressing this problem?

Answer 4

Add a gastroc pad to prosthetic socket

Add a 1 ply prosthetic sock over liner.

Question 5

Myodesis can be described as?

Answer 5

The suturing and permanent attachment of a muscle to a bone.

Question 6

Which of the following is not part of a Symes amputation procedure?

Answer 6

Transmetatarsal amputation.

Question 7

Myoplasty can be described as?

Answer 7

The suturing or permanent attachment of a muscle to another muscle.

Question 8

What are two advantages of myodesis over myoplasty with regards to amputations:

Answer 8

Decreased rate of muscular atrophy.

Decreased rate of antagonistic muscular imbalances.

Question 9

During normal heel strike, the forward hip is how flexed:

Answer 9

25 degree flexed.

Question 10

Which style of muscular tissue management in an TH amputation would be of greatest advantage to a myoelectric prosthesis candidate?

Answer 10

Myodesis

Question 11

A TF patient is see in clinic that exhibits lateral/proximal loss of contact in stance. Upon prosthetic fit examination it is noted the lateral wall is superior to the greater trochanter, the anterior wall contours to the adductor longus tendon the posterior socket does not encompass the ischial tuberosity, the medial wall is located 65mm inferior to the perineum. What do yo attribute to the cause of this deviation?

Answer 11

The posterior wall does not have ischial containment k.

Question 12

With a Krukenberg procedure what muscle is the driver of the pincer grip?

Answer 12

Pronator teres.

Question 13

What would be a good quality(s) to look for in a prosthetic foot for a TT amputee who is a K2 designated household ambulator that utilizes his prosthesis efficiently during the day but fatigues in the evening and buckles at the knee secondary to quadriceps weakness?

Answer 13

Foot that progresses rapidly into plantar flex ion during loading response.
Heel should have a relatively soft durometer.

Question 14

A TT patient is seen presenting with a traditional exoskeletal PTB prosthesis with a SACH foot. Patient states that see feels like to prostheses is throwing her knee forward as soon as the heel firmly contacts the ground. She has worn this prosthesis comfortable for two years until one month ago. What is the first clinical action you should tale at this time in the appointment?

Answer 14

Check to see if the patient switched to a shoe with a higher heel height compared to what she used to wear.

Question 15

The Krukenburg procedure is used at times in developing countries where expensive prosthesis are not attainable. What other patient population would this be potentially used for?

Answer 15

Blind patients with bilateral below elbow amputations.

Failed prosthetic use for bilateral below elbow amputations.

Question 16

A TR patient is seen in your clinic. Patient is inquiring as to which terminal device would be best for picking up a small coin from a table Which device would be recommend:

Answer 16

5XA

Question 17

What are simple options(s) for increasing the ease of pre-positioning the prosthetic elbow?

Answer 17

Moving the forearm lift tab anterior/distally

check level of resistance on cable housing.

Question 18

What boney landmark utilized for weight bearing in a hip disarticulation?

Answer 18

With a hip disarticulation you should utilize the ischial tuberosity just as with an above the knee prosthesis

Question 19

What is a option for pre-positioning the prosthetic elbowin flexion, for a TH amputee utilizing an triple control body powered prosthesis who lacks glenohumeral flexion strength and biscapular abduction strength but can operate an elbow lock?

Answer 19

Change the triple control to duel control, switch split housing to single housing, utilize ballistic motion for forearm lift.

Question 20

Why is choosing a SACH foot with a firm heel durometer not advised for TT patients with poor prosthetic side knee stability”

Answer 20

It will decrease knee stal

Question 21

You are doing a gait assessment-with your patient that has a below knee prosthesis side. Choose that choice that would NOT be a potential cause of this gait deviation?

Answer 21

Weak quadriceps.

Question 22

A TF patients seen in your clinic It is noted that as he ambulates with a circumducted gait. Select ALL possible causes?

Answer 22

Prosthesis height is longer than his sound side ischial tuberosity to floor measurement.
Prosthetic suspension is not adequate
The user does not have adequate hip flexor strength
Prosthetic foot is plantar flexed excessively.

Question 23

ATF patient isseen in your clinic. Instance, the prosthetic foot”smears” externally as she simultaneously abducts her prosthesis whereby advancing forward in the sagittal plane. She complains of low back pain as well. What is a prosthetic cause?

Answer 23

Not enough flexion is build into the socket.

Question 24

A patient with an above knee amputation has a prosthesis. During gait analysis you find that she has knee instability while standing and you see knee buckling with any weight shift. You suspect the cause of the instability is?

Answer 24

Prosthetic knee set too far anterior to the TKA line.

Question 25

Transtibial Prosthic socket that are excessively extended casue excessive pressure on what areas?

Answer 25

Anterior proximal, posterior distal.

Question 26

Transtibial Prosthic socket that are excessively extended casue excessive pressure on what areas?

Answer 26

Anterior proximal, posterior distal.

Question 27

True or false outsetting the prosthetic foot in a transtibial socket increases medial distal and lateral proximal pressure?

Answer 27

True this causes a valgus moment at the knee.

Question 28

A four quarter amputaiton removes what structures?

Answer 28

Arm, clavical and scapula.

Question 29

In a transtibial patient you notice a mild extension moment at the knee in stance phase. what could be the cause, note alignment is proper?

Answer 29

Prosthetic Heel is to soft, this will cause the ground reaction force to be anterior to the knee whereby causing an extension moment in stance.

Question 30

What choosing if a prosthetic pateint is a gel liner canidate, which options would assist you in your decision?

Answer 30

Hygiene- optimal area for bacteria breeding
hand dexterity- may cause donning to be difficult
Activity Level- is important as gel durometer varies from model to model which may impact your decision
Allergies- gel composition veries between manufactures and models allergies need to be considered.

Question 31

In a transmetarsal amputation you would expect to see what gait deviation?

Answer 31

Absent push off, with transmetatarsal amputaion gait deviation include limited push off on the affected side along with deminished stance phase. you would not expect to se any other gait deviations as the muscle tendinous insertions remain intact to perform dorsiflexion and supination?

Question 32

Dorsiflexion the socket is synonymous with?

Answer 32

Flexions the socket.

Question 33

Why is it important to utilize the Berkeley alignment componentry prior to final fabrication of an exoskeletal prosthesis?

Answer 33

Allow you to align the prosthesis properly as exoskeletal prosthesis cannot be realigned.

Question 34

What muscle would you expect to be the weakest in an above knee amputation?

Answer 34

Hip adductor- due to their transection, the shorter the amputation the weaker expected. hip extension may be sligthly weaker due to the loss of adductor magnus whcih aids in extensions.

Question 35

In an AK patient, when ambulating the patient complains of knee instability. What alignment change could assist in regaining knee stability?

Answer 35

Move the prosthetic knee posterior to the socket.

Question 36

When flexing an AK socket to accomodate a hip flexion contracture what cocurrent alignment should be made?

Answer 36

Move the prosthetic knee posterior to keep the knee stable.

Question 37

In a knee disarticulation amputee what is the concern is a cosmetic concern?

Answer 37

what the knee extends too far out past the sounds side with sitting or kneeling– not a trun leg length discrepancy.

Question 38

When abulation a patient complains of knee instability, what alignment change could possibly assist in regaining knee stability

Answer 38

Extend the prosthetic socket, by making an aigular adjustment moving the prosthetic socket into extension we can decrease ground reaction forces running posterior to the knee center whereby promoting knee stability.

Question 39

When making an angular change utilizing endoskeletal componentry it is necessary to?

Answer 39

Loosen bolt opposite direction of desired angulation and tighten the bolt on the side of the desired angulation.

Question 40

Choose all the benefits of a knee disarticulation over an above knee amputation?

Answer 40

Rotational control
natural weight bearing surface
muscle balance between adductors and abductor
larger surface area for prosthetic socket.

Question 41

When removing endoskeletal prosthetic componentry for adjustment, how do you saveyour orginal alignment.

Answer 41

Completely back out two adjacent bolts.

Question 42

In general polycentric knees are consdiered inherently stable, Why is this?

Answer 42

Polycentric knees have a theroetical knees center that is located posterior and superior.

Question 43

What is the scarpus triangle made of?

Answer 43

Inguinal ligament
sartorious
adductor longus.

Question 44

Benefits of a polycentric knee?

Answer 44

Inherently stable
increased cosmesis when sitting
shortened swing–> greater foot clearence in AK patients.

Question 45

In an Transtibial patient, when trying to increase the energy return of a dynamic response foot it may be necessary to incease plantarflexion

Answer 45

True– by planterflexing the foot, forefoot pressure increase relatively earlier instance, which allows greater energy to builds up “stored” to be released in terminal stance.

Question 46

The gait cycle is composed of what?

Answer 46

Heel strike on one side followed by heel strike on the same side.

Question 47

A transhumeral patient seen in clinic, they are utilizing a body powdered prosthesis with a hosmer mechanical elbow and complain that he can operate it throughout it full range of motion but it requires too much effort, what can be done to remedy this?

Answer 47

Install a spring lift assist–> you will decrease and amount of effort required to flex the prosthetic elbow thorughout the ROM.

Question 48

What is a simply option for prepositioning the prosthetic elbow in flexions, for a transhumeral amputee utilizing a body powdered prosthesis who lacks glenohumeral flexion strength and biscapular abduction strength but can operate an elbow lock?

Answer 48

Move the proximal base plate and retainer on humeral section anterior–> by moving the control cable retainer on the humeral section anterior you move the pull angle anterior to bridge the elbow joint whereby decreasing the force necessary to move the forearm section about the humeral section.

Question 49

During many amputations the surgeon will perform a myoplasty, what is this?

Answer 49

Attaching muscle to muscle.

Question 50

True or false, when fabricating Transradial figure 8 harness, it is necessary to incorporate elastic material to the control strap?

Answer 50

False- in a figure 8 harness inelastic matral must be utillzed to capture maximal cable excursion where as excursion will be lost within the elastic material.

Question 51

The inverted Y strap on a figure 8 harness should be located what on the body?

Answer 51

Delto-pectoral groove.

Question 52

What muscle is responsible for scapular elevation?

Answer 52

Trapezius (upper traps specifically).

Question 53

A transfemoral patient is seen in clinic, upon doffing the suction socketyou notice red, wart like formation and crakced skin distally, choose the name and cause of this condition?

Answer 53

Verrucouse hyperplasia , cause by lack of contact or a void distally, when utilizing a suction socket in an AK application a distal void can cause excessive draw or “Hickey” effect on the distal residual limb tissue

Question 54

A transhumeral patient is utilizing a body powdered prosthesis and is wondering which terminal device would be best suited for holding a broom handle.

Answer 54

555- is a symmetrically shaped “lyer shaped” hook that is ideal for holding round objects.

Question 55

With a hip disarticulation prosthesis, what is used for suspension?

Answer 55

The whole iliac crest is used for suspension of hip disarticulation prosthesis.

Question 56

When fitting a figure 8 harness with a NW ring on a transradial, why is it advantageous to locate the NW slightly towardsthe sound side and at level of C7.

Answer 56

By placing the NW ring slightly towards the sound side and at the level of the C7, the control strap will lie across the affected side scapula allowing the most effcient excursion of the control cable.

Question 57

When recommending a ischial containment socket what are some of the biomachanical goals that accompany this socket?

Answer 57

The ishcial seat provides a weight bearing surface,

By containing that ischium we decrease distal lateral discomfort in weight bearing.

Question 58

With upper extremity majority of supination and pronation occur at with joint?

Answer 58

Distal radioulnar and proximal radio ulnar.

Question 59

In a transfermoral patients socket fitting evaluation that ischial-turbeosity is not located on the seat but rather further down the socket, what could you do to remedy this?

Answer 59

Add a prosthetic sock

add padding adjacent to the scarpus triangle.

Question 60

Standard bench alignment of a transtibial prosthesis with a SACH foot in the coronal plane is?

Answer 60

0-12mm inset in the coronal plane helps aid in mild genu varum moment at midstance wich keeps the body centerof mass over the base of support “ the prosthetic foot”.

Question 61

In a below elbow amputation the muscles that are transected are?

Answer 61

Flexor Carpi Radialis
brachioradialis
pronator quadratic.

Question 62

A transtibial patient seen in clinic, the patient has been utilizing a Transtibial prosthesis successfully for 10 years but the patient has a grade 1 osteocondral defect “OCD” to his medial femoral condyle that is painful in weight bearing. What alignment could you incorporate to assist in the patient discomfort?

Answer 62

Outset foot, by outsetting the foot you can create geun valgum moment at the knee in weight bearing, by creating an external geun valgum moment you can assist in opening the medial knee compartment and pressure over the OCD.

Question 63

Many prosthetic knees require the toe to be loaded and then un weighted in order to transistion from stance phase to swing phase. why would recommending two knees that function in the way toa bilateral TF amptuee be contraindicated?

Answer 63

Becuase the patient wouldn’t be able to sit, because they would not be able to unlock both knees.

Question 64

What muscle is the primary forearm supinatior?

Answer 64

Biceps brachii innervated by musculocutaneous nerve is the primary forearm supinator. also it acts to flex the forearm when supinated. brachialis flexes forearm in all positions. Coracobrachialis helps to flex and adduct the arm. Brachioradialis is one of the elbow flexors innervated by the radial nerve.

Question 65

In a TT prosthesis, excessive adduction of the pylon would cause what at midstance in gait?

Answer 65

Geum Varum by adducting the prosthetic pylon you would be bringing the prosthetic foot closer to midline whereby bringing the prosthetic foot “base od support at midstance” medial to the center of mass above causing a varum moment at the knee.

Question 66

One characteristics of a TT total surface bearing socket is?

Answer 66

pressure equilization across all residual limb surface. total surface bearing sockets are designed to equalize pressure across a greater surface area of the residule limb.

Question 67

With a knee disarticulation what adductor muscle is transected?

Answer 67

With knee disartulation the gracilis muscle along with sartorius and hamstrings are transected.

Question 68

When evaluating a new trans metartsal amputee what deofrmity of the foot and ankle complex is typical without tendon transfer?

Answer 68

Equino varus– peroneus longus is transected, this causes weakness of pronators allowing suponators muscle to override the foot and ankle complex in an equino varus deofrmity.

Question 69

The most accurate description of a hydraulic single axis knee is?

Answer 69

Fluid prosthetic knees fall into two categories (pueumatic- gas) (hydraulic- liquid) therefore a hydrulic or pnrumatic knee utilizes “fluid” resistance to modify TF prosthetic.

Question 70

All of the following muscles make up the pes anserinus execpt?

Answer 70

Semi-membranous– inserts along the posterior aspect of the midial condyle of the tibia where the pas anserinus inserts on the medial surface of the superior part of the tibia.

Question 71

When evaluating a TF prosthetic knee, which type of resistance is most adversely effected by cold enivornmental changes?

Answer 71

Hydraulic fluid becomes more viscous in cold temps, making response of the prosthetic knee sluggish in response to cold temps.

Question 72

In TF prosthetics alignment the relationship between the posterior socket shelf and the lateral wall is referred to as?

Answer 72

The adduction angle, the Q angle is the angle between the quad muscle and the patella tendon.

Question 73

When determining the corredect length of the prosthesis what bony landmark is NOT used?

Answer 73

The greater trochanter is not a bony landmark used for proper height measurment, the ASIS, PSIS, and Iliac crest along with the medial plateau are all used to establish the proper length of the prosthesis.

Question 74

A TT patient is seen in a clinic, at heel strike the SACH prosthetic foot retates externally. what would cause the gait deviation?

Answer 74

The prosthetic heel is too firm– if the prosthetic heel is too firm, at heel strike instead of absorbing the energy, the force is translated laterally causing rotation externally. Note this cant also be caused if a SACH foot is squeezed into a shoe too small. The tight fitting shoe does not allow for the proper compression of the SACH hell, essentially fasely creating a “firm heel”.

Question 75

The force of 2lbs is exerted on a 1.5 foot lever arm. What amount of force must be exerted on a 2 foot lever arm balance of system?

Answer 75

1.5 lbs. (2 *1.5= 2 * X) solve for X = 1.5lbs.

Question 76

The biceps femoris causes what motiion at the hip and knee respectively?

Answer 76

Hip extension knee flexion,– biceps femoris along with semitendinosus, and semimembranosis makes uo the hamgstring, due to its promixal attachement at the ischial tuberosity it acts to extend the thigh, distal attachment on lateral side fibula will assist with knee flexion.

Question 77

A TF pateint seen in clinic, a medial whip is noted in the prosthetic gait. What adjustment would be appropiate to normalize the swing phase alignment?

Answer 77

Internally rotate prosthetic knee,– medial whips are caused by excessive externally rotated prsothetic knees and are fixed by externally rotating the prosthetic knee.