Prosthetic Prep Exam 22 Flashcards
When a prosthetic foot inset is increased, socket pressure will become more apparent?
Lateral distal/ medially proximal.
During normal gait you see the pelvis drop during midstance, what muscle weakness could cause this?
Gluteus medius– weakness in the gluteus medius will cause what is know as trendelenburg gait. One function of this muscle is to maintain lateral stability of the pelvis.
What is the maximum, amount of knee flexion contracture that could be fit with a traditional TT PTB socket?
25 degrees– they still can be fit with a traditional PTB socket, but further contractures may indicate a bent knee prosthetsis. which has very poor cosmesis.
What mucles of the quads will help steady the hip joint and help ilioposoas flex the him?
Rectus femoris– primarly due to the proximal attachment at the anterior inferior iliac spine.
When evaluating the mechanics of a prosthetic foot, it could be said that a prosthetic keel acts like which muscle group, and what type of contraction?
The plantarflexors, and eccentric contraction– the prosthetic foot keel is acting like ankle plantarflexors eccentrically contracting where by controlling the anterior translation of the prosthetic pylon and socket over the foot in stance.
When aligning the prosthetic socket, posterior to the prosthetic foot, forces present in the socket to increase where?
Anterior proximal/ posterior distal– when moving the socket posterior in relation to the prosthetic foot length of the prosthetic foot keel is relatively longer causing an extension moment at te knee in midstance as well as increased socket pressure anterior proximal/ posterior distal
When fabricating a below knee socket for a 4 year old patient it may be necessary to make a socket that includes multiple removable layers, called a “onion skin lamo”?
True— by providing removable layers this will allow for accommodation to the natural girth/volume change of the child as he/she grows. This will minimize the number of socket replacements.
In a TT patient seen at clinic, when evaluating gait you notice trendelenberg sign, on the prosthetic side during midstance. What muscle group would you expect to show low MMT scores on the prosthetic side?
Gluteus medius– gluteus medius is a hip abdutor, when this muscle is weak, the patient will lean over the involved side (trendelenberg sign) to create abduction whereby maintaining stability.
For a prosthetic patient utilizing a cane in rehab, why is it recommened that the cane be held in the opposite side of involvement?
The tripod is one of the most stable bases. In prosthetics this is created by the prosthetic side forwrad, ssoundsisde lower extremity back and uninvolved side hand with cane. In a normal gait during swing phase of the prosthesis, the contralateral arm swings to oppose the rotational torque “dog chasing tail” and allow forward progression to occur. with use of cane it will allow for potential equalized step length. Having the cane does promote knee stability and confidence with prostheic patient early on in their rehabilitation.
All are bony landmarks are easily palpable on the lower limb execpt?
The lesser trochanter cannot be palpated as it is on the proximal medial surface of the femur covered by soft tissue of the adductors.
A TF patient is seen in clinic, if the patient is utillizing suction suspension you can best differenciate the socket pressure as __________ in stance and ____________in swing phase?
Suction suspension provides positive pressure as the patients weight is going through the socket in stance phase and also negative pressure during swing phase.
An elbow disarticulatiuon patient is seen in clinic for a socket replacemment, what type of articulation at the elbow is indicated?
Outside locking hinger – allow center to be matrched in a long TH or ED they allow the patient to lock the elobw in multiple positions similar to a TH user with a hosmer locking elbow. note cosmesis can be poor.
T/F When fabricating a prostrhetic socket in general it is necessary to have all “like” fibers directly adjacent to aid in strength?
Why are flexible elbow hinges recommended for longer amputees. allow patient to maintain natural pronation/supination– by utilizing flexible hinges for langer TR amputees we can allow their natural pronation/supination to occue without the prostheic hinges impeding the motion.
False by alternating different fibers types in your lamination you can utilize principals similar to the I-beam effect.
When deciding to add a cross back strap to a figure of eight harness, which material would be best to fabricate a crosee back strap with?
An elastic strapping– cross back straps are used to promote increased excursion inelastic materals are ideal as they will capture more body motion in the form of a cable excursion where as elastic material will capture the excursion in the elasticity of the materals vs. cable excursion.
Why are flexible elbow hinges recommended for longer amputees. allow patient to maintain natural pronation/supination– by utilizing flexible hinges for langer TR amputees we can allow their natural pronation/supination to occue without the prostheic hinges impeding the motion.
By utilizing flexible hinges for langer TR amputees we can allow their natural pronation/supination to occue without the prostheic hinges impeding the motion.?
Partial foot amputees often present with a lack of controlled third rocker late in stance. what option can assist with this other thana partial foot insert with toe filler?
1) rigid sole shoe
2) rocker addition to shoe sole
3) carbon insert
4) OTS carbon AFO
When recommending a prosthetic Bilateral to a TR patient what style of suspension would you not recommend?
Munster self suspending sockets are contraindicated for bilateral TR amputees as they require a pull sock to be utilized for dinning the prosthesis which requires at least one sound hand to assist in the process
When fabricating a TH prosthesis it is important to add pre-flexion to the prosthetic elbow why is this?
By preflexing the prosthetic elbow in a TH application, a mechanical advantage is placed into the prosthetic system that will decrease the the force necessary to initiate elbow flexion whereby increasing the ease of operation on the amputee.
Transverse tarsal joints allow inversion and eversion of the foot. choose the other joint that allows inversion and eversion?
Inversion and eversion occur at subtalor, talocalceonavicular and transverse tarsal joints. Superior and inferior tibiofibular joints assist with proflexion and dorsiflexion.
With respect to TF quad socket measurements, which measurements would the following calculation be used for … meausre the ischial level circumference and divide it by three than subtract 6mm?
By measuring the ishcial level circumference, dividing by 3 and than subtracting 6MM you are determining the M/L measurement for a quad socket.
A TR patient needing the ability to very grip force on small delicate objects would benefit from which terminal device?
A voluntary closing hook offers ease of sight to the object as will as a variable “graded” grip force which can allow the patient to determine the exact amount of grip force they intend to use on the object.
Injury to the superior gluteal nerve will result in what gait deviation?
Trendelenbrug sign. –>superior gluteal nerve innervates gluteus medius and minimus, with injury these muscles are incative causing the pelvis to fall on the raised limb.
A force of 9lbs is applied to the harness in a TR prosthesis, in order to maintain the minimum acceptable efficiency of the cable/cable housing, how much force must be needed in order to open the prosthetic hook?
6.3 lbs, 70% is the minimum accepted cable/cable housing efficiency (9lbs * .7 = 6.3lbs)
When modifying a TF quad plaster mold, if you are trying to increase the amount of adduction on the mold what must you do to maintain a level posterior shelf?
Shave plaster off laterally, by increasing the the adduction angle the medial posterior shelf is relatively raised, by then removing plaster laterally you can level out the posterior shelf and maintain proper ishcial tubersity dista end length.
The talus does not articulate with the?
Cuboid does not articulate with the talus
When fabricating TF socket with a hip joint, the hip joint should be located where in relation to the greater throchanter? 12mm anterior, and 25.4 mm superior–> socket hip joints location should match anatomical hip joint location for proper articulation. the anatomical hip joint location is 12mm anterior and 25.4mm superior to the greater trochanter.
12mm anterior, and 25.4 mm superior–> socket hip joints location should match anatomical hip joint location for proper articulation. the anatomical hip joint location is 12mm anterior and 25.4mm superior to the greater trochanter.
In TF application when inadequate socket flexion in incorporated into the prosthesis what will the patient be unable to do without a gait deviation?
Have symmetric step lengths–> proper flexion angle must be incorporated into the TF prosthesis in order to allow even step length when compared to the sound side.
The tibial nerve innervates muscles to the ________ portion of the leg, while the deep fibular nerve innervates muscles on the _______ protion of the leg?
Posterior, anterior –> the tibial nerve supplies posterior muscles of the leg and knee joint, while the deep fibular nerve supplies anterior muscles of the leg and dorsum of foot.
A TT patient in clinic, the patient has been utilizing a TT prosthesis without problem for years, the patient have PVD and has been expirencing ischemic pain within his prosthetic socket in what seems to be his gastroc muscle. What should be the most logical plan of action?
Decrease pressure on posterior and adjacent to the popliteal artery, recommend the patient be seen by a vascular specialist –> by decreasing pressure adjacent to the popliteal artery we can minimize ischemic pain as blood flow will be less restricted, all patients with new medical symptoms should be refereed to a physician for evaluation
T/F with regards to initial post operative porsthesis and rigid dressings, removing the device is indicated if the patient is running a temp beucase is it a hallmark sign of an infection?
True–> often you will be asked to remove the IPOP or RIGID cast, if the patient spikes a fever as it is a sign of infection which merits would examination note: in instance where more frequuent would chekcs are needed for a patient with infection a bi-valved deisgn can be more comvenient or a thermoplastic RRD.
You place a shrinker on a BK amputee patient 3 weeks post op and notice the he keeps a pillow under his knee, what joint would you expect a contracture if this persists?
Knee flexion and hip flexion contracture.
T/F when performing plaster mold modifications for a lateral stabilization bar in a TT PTB style socket, it is imperative that is does not extend too superior so as to aviod the common peroneal nerve?
True–> lateral stabization bar is located in between the fibular head and the cut end of the fibular, it should be located distal to the fibular head and proximal to the cut end to aviod pressure adjacent to the cut end and common peroneal nerve.
