P&O SAEs Flashcards
Comparing lower limb amputations to upper limb amputations in the United States, lower limb
amputations are
(a) most often due to trauma.
(b) expected to significantly increase over the next 20 years due to increasing rates of
diabetes mellitus.
(c) less common than upper extremity amputations.
(d) expected to decrease over time due to improved prenatal care leading to less congenital
malformations.
Answer (b)
Commentary: The prevalence of diabetes mellitus continues to increase in the United States and
this trend is expected to cause increasing rates of lower extremity amputation. Lower extremity
amputations are more common than upper extremity amputations and are more likely to be
related to dysvascular causes. Despite improvements in prenatal care enabling more births, rates
of amputations due to congenital defects have not changed significantly. The most common cause
of upper extremity limb loss is trauma-related injury.
What is the primary benefit of using a postoperative, rigid, non-removable dressing in a new
transtibial amputee?
(a) Improved monitoring of postoperative wounds
(b) Protection of the wound and edema control
(c) Prevention of hip flexion contractures
(d) Improved strength in the residual limb
Answer (b)
Commentary: The primary benefits of a rigid dressing include wound protection, edema control
and prevention of knee flexion contractures (not hip flexion contractures). Monitoring the wound
may be more difficult with a non-removable rigid dressing. The dressing should be removed for
wound check regularly and if there is a concern for infection. Type of postoperative dressing has
no effect on residual limb strength.
A 45-year-old man with a history of transtibial amputation secondary to trauma presents to your
office 6 months following surgery. He is successfully ambulating independently with his
prosthesis. His chief complaint today is new mild phantom limb pain. Evaluation does not reveal
any significant problems with his prosthesis or gait. What treatment would you recommend to
decrease his phantom limb pain?
(a) Cryotherapy
(b) Ultrasound
(c) Desensitization
(d) Paraffin wax
Answer (c)
Commentary: First line treatment for phantom limb pain should include use of desensitization
techniques (massage, friction rubbing, wrapping, etc.) The other types of therapeutics listed
would not be effective in phantom limb pain management. Phantom limb pain is one of many
sources of pain in an amputee and is difficult to treat. It affects anywhere from 67% to 79% of
amputees. For patients whose pain interferes with function and quality of life, a biopsychosocial
approach to pain management is crucial.
A 49-year-old man is seen in your outpatient clinic 2 years after a stroke. You notice a
Trendelenberg gait and suspect weakness of which muscle?
(a) Gluteus maximus
(b) Quadratus lumborum
(c) Quadriceps
(d) Gluteus medius
Answer: (d)
Commentary: Weakness of the gluteus medius muscle, or reluctance to use the gluteus medius
muscle because of hip pain, can cause this gait pattern. It is a pattern of either excessive pelvic
obliquity during the stance phase of the affected side (uncompensated) or excessive lateral truncal
lean during the stance phase on the affected side (compensated).
In a transfemoral amputee, a circumducted gait pattern, on the prosthetic side, could be caused by
which factor?
(a) Insufficient prosthetic knee friction
(b) Long prosthetic limb
(c) Hip flexion contracture
(d) Poor balance
Answer (b)
Commentary: When observing gait deviations in an amputee, one should consider both the
prosthetic issues and amputee compensatory maneuvers as a potential cause for the deviation. A
circumducted gait pattern can have various causes, including a long prosthetic limb, excessive
prosthetic knee friction (making it difficult to bend the knee), and hip abduction contracture. Poor
balance is usually associated with excessive lateral trunk bending, uneven arm swing, and short
stance phase on the prosthetic side.
A 65-year-old woman with diabetes mellitus has been sent to your clinic for evaluation of
appropriate footwear. She had a diabetic foot ulcer 2 months ago over her first metatarsal head,
which is now healed. Examination reveals distal sensory loss and a mild claw foot deformity.
Which footwear/orthotic recommendation is the most appropriate?
(a) Since the wound is healed, no specialized footwear is needed.
(b) Well-fitting regular tennis shoes or sneakers are the best option.
(c) Off-the-shelf diabetic shoe with a custom molded orthotic based on severity of claw foot
deformity is indicated.
(d) Patellar tendon-bearing ankle-foot orthoses to help unload the metatarsal head should be
used.
Answer (c)
Commentary: The patient is at high risk for future diabetic foot ulcers based on her history of
previous ulcers, claw foot deformity and peripheral neuropathy. Based on this risk profile,
specialized footwear is recommended. Patients with diabetes mellitus (DM) without risk factors
for ulcer could be counseled and educated regarding the use of well fitting tennis shoes and
sneakers. While a custom molded shoe could benefit this patient, they are very expensive and
usually needed for patients with severe foot deformity. At this point a prefabricated diabetic shoe
and custom orthotic would be clinically appropriate and more cost-effective. A patella tendon
bearing ankle-foot-orthosis is not indicated and would not effectively offload the metatarsal
heads. A metatarsal bar or pad placed proximal to the metatarsal head is an effective way to
offload the metatarsal head.
- Of the following modalities, which is the most effective in treating phantom limb pain?
(a) Iontophoresis
(b) Transcutaneous electrical nerve stimulation
(c) Short wave diathermy
(d) Paraffin baths
Answer: (b)
Commentary: Of the options listed, transcutaneous electrical nerve stimulation (TENS) is the
modality that may be useful in treating phantom limb pain. Iontophoresis is generally used for
dispersion of medications. Short wave diathermy is a method of deep heat. Paraffin bath is a
superficial heat modality.
- A patient with a left transfemoral amputation demonstrates a lateral trunk lean towards his
prosthetic side. What is the most likely cause?
(a) Prosthesis too long
(b) Long residual limb
(c) Prosthesis aligned in adduction
(d) Hip abduction contracture
Answer: (d)
Commentary: Causes of lateral trunk lean towards the prosthetic side include: prosthesis too
short, hip abduction contracture, prosthesis lined in abduction, and short residual limb.
- Proper positioning for a transtibial amputee should include use of a
(a) pillow underneath thigh.
(b) pommel between legs.
(c) limb board underneath knee.
(d) wedge cushion underneath buttocks.
Answer: (c)
Commentary: A limb board placed underneath the knee will help to prevent knee flexion
contractures. Placing a pillow underneath the thigh would encourage the development of a hip
flexion and possibly a knee flexion contracture. A pommel between the legs may encourage a hip
abduction contracture. A wedge cushion would promote hip flexion contractures.
- Upper extremity exercise (eg, crutch walking) leads to a greater increase in heart rate and blood
pressure compared with lower extremity activity (eg, normal walking) due to the
(a) smaller upper extremity muscles, which contract at a higher maximal percentage.
(b) proximity of the upper extremities to the heart and major blood vessels.
(c) upper extremities having to overcome the effect of gravity.
(d) greater range of motion of the upper extremities compared to the lower ones.
Answer: (a)
Commentary: Upper extremity work leads to greater increases in heart rate and blood pressure.
When a muscle contracts with a given percentage of its maximum force, its effect on blood
pressure is about the same as during the same percentage of contraction of any other muscle. The
smaller muscles in the upper extremity contract more, and stimulate the cardiovascular system
more relative to the larger lower extremity muscles.
- Which cervical orthosis is the most restrictive?
(a) Four-poster brace
(b) Philadelphia collar
(c) Sterno-occipital mandibular immobilizer (SOMI)
(d) Halo
Answer: (d)
Commentary: The halo device provides the greatest restriction of cervical motion for
flexion/extension, lateral bending and rotation, as shown in the table below:
Table 1: Percentage of Cervical Motion Permitted by 4 Cervical Orthoses
Orthosis % Flexion/extension %Lateral Bending % Rotation
Philadelphia collar 28.9 66.4 43.7
SOMI brace 20.6 65.6 33.6
Four-poster brace 20.6 45.9 27.1
Halo device 4.0-11.7 4.0-8.4 1.0-2.4
- You are performing a consultation on a 58-year-old man with a history of diabetes and peripheral
vascular disease who presents with a non-healing foot ulcer. You are concerned that he is at risk
for amputation because his
(a) ankle brachial index (ABI) is 0.8.
(b) ABI is 0.4.
(c) transcutaneous oxygen pressure (TcPO2) is 80mmHg.
(d) TcPO2 is 40mmHg.
Answer: (b)
Commentary: ABI is a noninvasive technique that is used in the assessment of arterial occlusive
disease. The ABI is the ratio between the ankle and the brachial systolic pressure. Normal ABI is
defined as values greater than 0.9. An ABI below 0.4 tends to carry a poor prognosis. TcPO2 is
defined as transcutaneous oxygen, which is in essence a “blood gas” of the skin. Normal TcPO2 is
greater than 50mmHg. Values of more than 40mmHg are associated with healing. Ischemia is
defined as periwound TcPO2 < 20mmHg.
- Which phenomenon is an effect of functional electrical stimulation (FES) as it pertains to gait?
(a) Decrease in muscle spasticity
(b) Increase in physiologic cost of gait
(c) Decrease in voluntary muscle strength
(d) Decrease in stride length
Answer: (a)
Commentary: In addition to a decrease in muscle spasticity, FES decreases the physiologic cost
of gait, increases voluntary muscle strength, and increases stride length.
- In prosthetics, K levels are used to describe or define
(a) activity levels.
(b) prosthetic feet.
(c) funding levels for prosthesis.
(d) etiology of amputation.
Answer: A
Commentary: K levels are used to describe activity levels These K0-K4 designations are guidelines for prosthetic components covered by Medicare.
- Which factor promotes knee stability during the gait cycle of a person with transfemoral amputation?
(a) Knee component placed anterior to the socket
(b) Hard heel in the prosthetic foot
(c) Polycentric 4-bar linkage prosthetic knee
(d) Anterior position of the shank on the prosthetic foot
Answer: C
Commentary: Flexion moment at the hip, a rigid heel in the solid ankle, cushion heel foot and the anterior position of the shank all shift the ground reaction force behind the knee joint to produce a knee flexion moment. The 4-bar linkage with instantaneous center of rotation and the posterior location of instant center in extension creates knee stability, especially at heel strike.
- The primary advantage of a soft insert fitted into the socket of a transtibial prosthesis is that it is
(a) perspiration resistant.
(b) easy to keep clean.
(c) easily modified.
(d) very durable.
Answer: C
Commentary: Soft inserts are fabricated to fit inside the socket. They are recommended for patients with thin, sensitive, or scarred skin, or peripheral vascular disease (PVD). They are easily modified. Hard sockets also have their advantages. They are perspiration resistant, less bulky than sockets fitted with a soft insert, easy to keep clean, and durable. Further, reliefs or modifications can be located with precision in the hard socket.
- How are mobility devices paid for through Medicare?
(a) The patient must make a 50% down payment, with the rest covered by Medicare upon delivery of the device.
(b) Medicare part A pays 80% of the allowed purchase price and Medicare part B pays the remaining 20%.
(c) Medicare will pay for purchase but not rental of mobility devices.
(d) Medicare part B pays 80% of the allowed purchase price in one lump sum.
Answer: D
Commentary: Medicare Part B pays 80% of the allowed purchase price in one lump sum payment if the patient chooses to purchase the device. The patient is required to pay 20% of the allowed purchase price. If the patient chooses to rent a wheelchair, Medicare part B will pay 80% of the allowed rental price for months 1 through 10 and the patient will pay 20% of the allowed rental charge.
- At mid stance, where is the ground reaction force vector located?
(a) Anterior to ankle, posterior to knee
(b) Anterior to ankle, anterior to knee
(c) Anterior to knee, anterior to hip
(d) Posterior to knee, posterior to hip
Answer: B
Commentary: In mid stance, the ground reaction vector lies anterior to the ankle, anterior to or through the knee axis, and posterior to the hip center. The passive torques created by this vector alignment are ankle dorsiflexion, knee extension and hip extension.
- What is the primary advantage of a body powered upper limb prosthesis compared to a myoelectric prosthesis?
(a) Greater sensory feedback
(b) Moderate or no harnessing
(c) Less body movement to operate
(d) Enhanced cosmesis
Answer: A
Commentary: The advantages of body powered upper limb prostheses include the following factors: moderate cost, most durability, highest sensory feedback, and a variety of prehensors available for various activities. Their disadvantages are that they require the most body movement to operate, have the most harnessing and require increased energy expenditure to use. Myoelectric and/or switch controlled upper limb prostheses have the following advantages: they require moderate to no harnessing, require fewer body movements to operate, have moderate cosmesis, provide more function in proximal areas and, in some cases, provide a stronger grasp. Battery powered prostheses are the heaviest and most expensive prostheses. They also require the most maintenance, provide limited sensory feedback and require extended therapy time.
- What is the minimal number of points of contact that an orthosis must have in order to exert rotational control?
(a) One
(b) Two
(c) Three
(d) Four
Answer: C
Commentary: Rotational control forces or moments across a joint are not effective unless there are at least 3 points of contact between the device and the limb segment.
- The primary stabilizing effect of the flexible lumbosacral orthosis is its ability to
(a) restrict spinal extension.
(b) prevent atrophy of trunk muscles.
(c) elevate intra-abdominal pressure.
(d) enhance kinesthetic feedback.
Answer: C
Commentary: Although they do not effectively restrict motion to a significant degree, flexible lumbosacral orthoses elevate intra-abdominal pressure, thereby unloading the spine and supporting structures. This action also provides inhibitory kinesthetic feedback and warmth. Long-term use of binders and other flexible lumbosacral orthoses may, unfortunately, result in atrophy of trunk muscles.
- Individuals with diabetes are at high risk of amputation despite ankle pressures greater than 55 mmHg because
(a) the ankle brachial pressure index must be greater than or equal to 0.3 to prevent limb threatening ischemia.
(b) ankle pressures seldom correlate with severity of symptoms and are unreliable.
(c) calcification of the arterial media results in a spuriously high pressure.
(d) transcutaneous oxygen partial pressures and not ankle pressures correlate with ischemia.
(c)
In patients with diabetes, amputation is a strong possibility, even with ankle pressures higher than 55 mmHg because spuriously high pressures can be present in these patients as a result of calcification of the arterial media. The ankle brachial pressure index (ABPI) is the patient’s brachial pressure compared to the ankle pressure. A resting ABPI greater than 1.0 is considered normal. Patients with intermittent claudication have an ABPI in the range of 0.5 to 0.7, and patients with rest pain or other symptoms of severe ischemia have an ABPI of less than or equal to 0.3. A pressure less than 50 mmHg at the ankle is associated with limb threatening ischemia.
- The most common reason for prescribing a plastic leaf-spring ankle-foot orthosis is to
(a) overcome ankle spasticity.
(b) reduce lower-extremity edema.
(c) prevent plantar flexion deformity.
(d) support weak ankle dorsiflexors.
(d)
A plastic leaf-spring orthosis (PLSO) is probably the most commonly prescribed type of ankle-foot orthosis (AFO). It substitutes for weak ankle dorsiflexors and provides some medial lateral stability. Severe spasticity of the ankle may require prescription of a solid AFO. A plastic spiral AFO may be prescribed for concomitant weakness of both the ankle dorsiflexors and plantar flexors when spasticity is absent.
- The gluteus maximus is primarily active during which part of the gait cycle?
(a) Pre swing
(b) Loading response
(c) Midstance
(d) Terminal stance
(b)
The gluteus maximus is primarily active from terminal swing through initial contact and loading response. During midstance, terminal stance, and pre swing the gluteus maximus is actually silent.
- Your patient demonstrates ipsilateral pelvic drop during gait. What is the most likely cause?
(a) Scoliosis
(b) Short contralateral limb
(c) Hip adductor weakness
(d) Weak hip extensors
(a)
Deformity in the spine presents with malalignment of in the pelvis as either contralateral or ipsilateral drop. Two other causes of ipsilateral pelvic drop are contralateral hip abductor weakness and short ipsilateral limb. Weak hip extensors are a cause of backward lean. In stance, a backward lean of the trunk substitutes for weak hip extensors.
- For a patient with hemiplegia who prefers to use his legs and push his wheelchair backwards, the wheelchair should be configured with
(a) the back edge of the seat lower than the front edge.
(b) a single arm drive mechanism on the non-hemiplegic side.
(c) the large wheel axle plate moved to a more anterior position.
(d) large wheels in the front and casters in the back.
(d)
The casters should lead the rear wheels for the most common direction of travel. This will help reduce the possibility of the user flipping over when hitting an obstacle and will make the chair more directionally stable.
- A potential benefit of osseointegration (the direct skeletal attachment of the prosthesis to bone) is
(a) elimination of poor prosthetic socket fit.
(b) ability to return to running activities.
(c) early prosthetic fitting.
(d) ability to perform heavy manual work.
(a)
The primary benefits of attaching a prosthesis directly to the skeleton are comfort, elimination of poor prosthetic socket fit, and elimination of skin problems. Recipients report improved sensory feedback from the skeletally attached limb. Limitations include a 2-stage procedure, which results in an extended time of non-weight bearing, and extended rehabilitation (up to 2 years). The procedure poses a significant risk of infection, and the recipient must limit running, jumping, and heavy manual work in order to minimize loosening of the prosthesis.
- An advantage of a knee disarticulation compared to a transfemoral amputation is that the knee disarticulation offers
(a) more options for a prosthetic knee.
(b) enhanced ability to create power during ambulation or running.
(c) better soft tissue coverage within the zone of injury.
(d) better prosthetic cosmesis.
(b)
Disarticulation results in a bulbus distal residual limb, which may complicate prosthetic fitting. Choice of prosthetic knee options for a person with a knee disarticulation, therefore, is limited and potentially excludes the newer, more advanced knee-joint designs. Benefits of a knee disarticulation over a transfemoral approach include greater tolerance to distal limb weight bearing, a longer lever arm to create power during ambulation and running, and improved sitting balance. Of note, functional outcome studies of trauma-related lower extremity amputees concluded that persons with through knee amputations had significantly poorer outcomes. These poorer outcomes are attributed to complications arising from soft tissue failure within the zone of injury.
- In adults, the prevalence of phantom limb pain, phantom sensation or residual limb pain after amputation is
(a) approximately 70% at 6 months postamputation.
(b) dependent on age at the time of amputation.
(c) directly related to surgical technique.
(d) primarily dependent upon the level of amputation.
(a)
Phantom sensation, phantom pain, and residual limb pain have all been reported about equally in over 70% of amputees 6 months or more after lower limb amputation. This is typically not dependent upon the person’s age at the time of amputation, the level of amputation, or surgical technique.
- Your adult patient with a spinal cord injury needs to access his bathroom in his standard-width wheelchair. If no turn is required following entry into the bathroom, the minimal width of the doorway should be
(a) 26 inches.
(b) 32 inches.
(c) 36 inches.
(d) 40 inches.
(b)
The proper minimum width of a doorway for a wheelchair without a turn is 32 inches. If a turn is involved, then the doorway width should be at least 36 inches.
- Which K level best describes an individual who is able to ambulate within the household, but not out in the community?
(a) K 1
(b) K 2
(c) K 3
(d) K 4
(a)
The K level of 1 represents that of a household ambulator; K 2 limited community ambulator; K 3 unlimited community ambulator; K4 a very active community ambulator. The household exception FIM score of 5 indicates a “modified independent” ambulator who can handle household distances (i.e., less than 50 feet) inside or out.
Ref: Nelson VS, Flood KM, Bryant PR, Huang ME, Pasquina PF, Roberts TL. Limb deficiency and prosthetic management. 1. Decision making in prosthetic prescription and management. Arch Phys Med Rehabil 2006;87(3 Suppl 1):S3-9
- When should upper extremity prosthesis fitting be initiated in the adult?
(a) Within the first month after amputation
(b) When residual limb strength is full.
(c) When the patient requests a prosthesis
(d) When residual limb volume has stabilized
(a) The first month after upper limb amputation is the optimal period for prosthesis fitting. Fitting should be initiated during this time to maximize the level of acceptance and use of the prosthesis
- Double limb stance is what percent of the entire gait cycle?
(a) 5%
(b) 10%
(c) 20%
(d) 30%
(c) The average double limb support is 20% and single limb support is 40% of the entire gait cycle. Stance phase accounts for 60% of the gait cycle and swing phase accounts for 40%.
- What is a possible cause for circumduction during mid swing in the transfemoral amputee?
(a) Insufficient knee friction
(b) Prosthesis too short
(c) Excessive medial brim pressures
(d) Inadequate hip extension
(c) Possible causes for circumduction in the gait of a transfemoral amputee include excessive mechanical resistance to knee flexion, prosthesis aligned with too much stability, prosthesis too long, increased medial brim pressures, inadequate suspension, patient lacks confidence or has inadequate hip flexion.
- In a transtibial amputee, ambulation with a prosthesis, instead of unilateral non-weight bearing (with crutches) results in
(a) higher rate of energy expenditure.
(b) lower heart rate.
(c) higher respiratory exchange rate.
(d) equivalent amounts of energy to walk the same distance.
(b) Transtibial amputees have a lower rate of energy expenditure, heart rate and oxygen consumption when using a prosthesis (vs. non-weight bearing crutch gait). The cardiovascular demand of crutch walking is high, with increased rate of oxygen consumption, increased heart rate, increased energy costs, and respiratory exchange rate in the anaerobic range.
- The primary goal of a knee orthosis is to
(a) prevent knee injury in athletes.
(b) control knee instability in the anterior direction.
(c) prevent recurvatum.
(d) decrease the quadriceps force across the knee.
(c) Knee orthoses are prescribed to prevent genu recurvatum and provide mediolateral stability. They may be used during sports and other activities to provide functional support for an unstable knee or during the rehabilitation phase following injury or surgery on the knee. The use of knee orthoses for the prevention of knee injury in athletes is controversial. The Swedish knee cage prevents recurvatum but permits flexion. The three way knee stabilizer gives good control of structural knee instability in the lateral, medial, and posterior directions.
- The primary advantage of mag wheels over spoked wheels in the performance of a wheelchair is
(a) lighter weight.
(b) reduced maintenance.
(c) more maneuverability.
(d) general preference by active wheelchair users.
(b) Although MAG wheels require minimum maintenance and wear well, spoked wheels are substantially lighter, more responsive, and are generally preferred by active wheelchair users.
For an individual who has C5 tetraplegia, orthotic splinting attempts to maintain the functional position of the hand. This usually includes
(a) closing the thumb web space.
(b) 30º to 40º of metacarpophalangeal flexion.
(c) promoting flattening of the palmar arch.
(d) supporting the wrist in 20º to 30º of extension.
(d) The functional position of the hand includes supporting the wrist in 20º to 30º of extension, supporting the palmar arch with the 4th and 5th metacarpals slightly anterior to the second and third digits. Metacarpophalangeal flexion of 30° to 40° would be excessive. The thumb web space should be preserved.
- A 10-year-old girl presents with scoliosis 5 years after sustaining a severe traumatic brain injury.
Radiographic studies reveal a 25° levoconvex curve from C8 to T12 with the apex at T4. After
consultation with the orthopedic surgeon, you prescribe a spinal orthosis. Which type of orthosis
should be used in this patient?
(a) Cervicothoracolumbosacral orthosis (CTLSO)
(b) Thoracolumbosacral orthosis (TLSO)
(c) Thermoplastic Minerva body jacket (TMBJ)
(d) Sterno-occipital mandibular orthosis (SOMI)
(a) A thoracolumbosacral orthosis is used for scoliosis having an apex at T9 or lower. A sternooccipital
mandibular orthosis immobilizes the neck. A thermoplastic Minerva body jacket is also
used for cervical immobilization. A cervicothoracolumbosacral orthosis such as the Milwaukee
brace extends from the pelvic section to the neck ring and has been shown to correct scoliotic
curves throughout that area.
In a patient with a transfemoral amputation, what is the most likely cause of excessive knee flexion
during ambulation?
(a) Hip flexion contracture
(b) Prosthetic knee alignment in an excessively posterior position
(c) Excessive socket extension
(d) Too soft a plantar flexion bumper in the heel
(a) One of the most common gait deviations in patients with transfemoral amputations is abrupt or
excessive knee flexion during ambulation. The prosthetic knee joint should normally be stable in
extension in stance phase from heel contact to foot flat. This stability is accomplished by aligning
the prosthetic knee axis posterior to the trochanteric knee ankle line. Adequate strength and range
of motion in hip extension are critical to maintaining this alignment. Thus, weak hip extensors and
hip flexion contractures can cause knee instability. Two prosthetic causes of knee instability are (1)
knee malalignment in an excessively anterior position relative to the hip and ankle joints, and (2)
excessive socket flexion. A plantar flexion bumper that is too stiff, extensive foot dorsiflexion, or a
change in shoe heel height from low to high may all promote knee flexion.
- A circumducted gait in a man with an above knee amputation is most likely due to
(a) a rigid heel in his solid ankle, cushioned heel (SACH) foot.
(b) inadequate friction in his prosthetic knee unit.
(c) his prosthetic foot being set in dorsiflexion.
(d) inadequate socket suspension.
(d) Inadequate socket suspension causes the prosthesis to be functionally too long. A rigid heel and
foot set in dorsiflexion would increase knee flexion movement. Inadequate friction would cause the
leg to “snap” into terminal extension.
- Which modification will make a rocker bottom sole most effective?
(a) Increase sole thickness with apex at the metatarsal heads.
(b) Provide a rigid sole with no shock absorption.
(c) Extend the length of the shoe to ½ inch beyond the longest toe.
(d) Ensure that arch length is measured 2cm proximal to metatarsal heads
(c) The sole of a shoe for an individual with a neuropathic foot should be shock absorbing. The rocker
sole allows ambulation with reduced pressures on the forefoot. This requires an addition to the sole
thickness with an apex 1cm proximal to the metatarsal heads for the sole to roll over the forefoot.
The length of the shoe must be ½ to ¾ inches beyond the longest toe to accommodate the natural
elongation of the foot in ambulation. The arch length is measured at the metatarsal heads.
Ragnarsson KT. Lower extremity orthotics, shoes, and gait aids. In: DeLisa JA, Gans BM, Walsh NE,
editors. Physical medicine and rehabilitation: principles and practice. 4th ed. Philadelphia: Lippincott-
Raven; ,2005. p1380-3.
A prescription for side joints and corset in a below knee prosthesis would be indicated in a patient
with
(a) a short residual limb.
(b) a slight degree of knee joint laxity.
(c) fluctuating limb volume.
(d) fragile skin.
(a) Side joints and corset are indicated for persons with short or damaged residual limbs, or those with
a high degree of limb laxity. Long-term users may also prefer to continue side joints and a corset
even without the aforementioned indications.
- The primary advantage of a sterno-occipital-mandibular immobilizer orthosis is its
(a) excellent limitation of cervical extension.
(b) ease of donning while the patient is supine.
(c) high level of patient comfort.
(d) excellent limitation of atlantoaxial motion.
(b) The sternal-occipital mandibular immobilizer (SOMI) is effective at limiting flexion, whereas the 4-
post orthosis restrains extension better. The SOMI can be applied to the supine patient without
having to rotate the individual. The SOMI is not comfortable. Overall, control of atlantoaxial
subluxation is difficult to achieve with orthoses.
- For a person who has C5 tetraplegia, orthotic splinting attempts to maintain the functional position
of the hand. This usually includes
(a) 1° to 20° of metacarpophalangeal flexion.
(b) supporting the wrist in 30° flexion.
(c) inhibiting metacarpophalangeal flexion.
(d) promoting flattening of the palmar arch.
(a) The functional position of the hand includes supporting the wrist in neutral to 30° extension,
supporting the palmar arch with the fourth and fifth metacarpals slightly anterior to the second and
third, 1° to 20° of metacarpophalangeal flexion, unimpeded, and preserving the thumb web space.
- The proper width of a doorway to allow transit of a power wheelchair without turning is at least
(a) 26 inches.
(b) 30 inches.
(c) 36 inches.
(d) 40 inches.
(c) The proper width of a doorway for a power wheelchair is at least 34 inches. Base would increase to
36 inches if a turn is involved. A manual wheelchair requires a 32-inch doorway. The minimum
turning space is a 5-foot radius for a manual wheelchair and a 6-foot radius for a power chair.
- In preparation for discharge from your rehabilitation unit, an individual with T12 ASIA A
paraplegia requests information regarding access to a home with 5 steps. You suggest a ramp that,
for every 1 inch in elevation, should have a length of
(a) 12 inches.
(b) 8 inches.
(c) 16 inches.
(d) 24 inches.
(a) Ramps must have a 12-inch length for every 1-inch rise in elevation. This ratio is a minimum
requirement. A ramp must often be longer for an individual with a higher level spinal cord injury to
be able to independently navigate it. When space allows, a longer, less steeply inclined ramp is
preferable.
- What does the acronym SACH stand for?
(a) Simple amputation, cadence heel
(b) Single axis, carbon heel
(c) Standard adult, control heel
(d) Solid ankle, cushion heel
(d) SACH is an acronym for solid ankle, cushion heel. The SACH foot has a cushioned heel that
compresses during heel strike, stimulating plantar flexion, and has a rigid anterior keel to roll over
during late stance. It is light, durable, and inexpensive, and is the orthosis most often prescribed for
juvenile and geriatric amputees.
- Which muscle is primarily responsible for clearance of the leg during swing phase?
(a) Iliopsoas
(b) Hamstrings
(c) Quadriceps
(d) Tibialis anterior
(d) Midswing is the continuation of the passive pendulum action of the leg. Foot clearance is
maintained by activity of the tibialis anterior.
- What is the arrow pointing to in this upper extremity prosthesis?
Picture:Passing down the anteromedial surface of the humeral section of the prosthesis, the proximal end in on the shoulder strap and the distal end of the cable engages in front of the elbow
(a) An excursion cable
(b) An anterior split cable
(c) The elbow-lock control cable
(d) The elbow flexion cable
(c) This is an elbow-lock control cable. Its proximal end originates at the anterior suspension strap and
its distal end engages the elbow-locking mechanism. The principal of the elbow-lock mechanism is
pull-and-release to lock, pull-and-release to unlock.
- The primary advantage of a 4-point crutch gait over a 2-point crutch gait is
(a) stability.
(b) speed.
(c) weight-bearing relief.
(d) efficiency of gait.
(a) The 4-point crutch gait has stability as its primary advantage. At least 3 points are always in
contact with the ground. It is more difficult to learn than the other gait patterns and is a relatively
slow form of ambulation. The 3-point crutch gait is used by patients with lower limb fractures,
amputations, or toe-touch weight-bearing. The 4-point gait pattern enables the crutch user to
eliminate all the weight-bearing on the affected lower limb. The 2-point crutch gait is much faster
than the 4-point gait and yet still provides some weight-bearing relief to both lower limbs
- One disadvantage to adding camber to a wheelchair is that it
(a) decreases side to side stability.
(b) exposes the hands to injury.
(c) results in poor ergonomic positioning of push rims.
(d) makes maneuvering in narrow spaces difficult.
(d) Camber has several advantages. The footprint of the chair is widened creating greater side to side
stability; camber allows quicker turning; camber helps to protect the hands by having the bottom of
the wheels scruff edges; and camber positions push rims more ergonomically for propulsion. A
disadvantage is that the increased width of the wheelchair may make it difficult to maneuver in an
environment made for walking (ie, narrow spaces).
- Abdominal belts worn by workers have been shown to restrict which motions in the lumbar spine?
(a) Lateral bending and rotation
(b) Lateral bending and flexion
(c) Rotation and translation
(d) Flexion and translation
(a) Research models have shown that abdominal support belts limit lateral bending and rotation. A
10cm leather belt increased stiffness at the torso during lateral bending, thereby reducing motion in
these planes. No changes in torso stiffness were noted, despite the belt being worn at full lumbar
flexion.
- Which knee component is preferred in the prosthetic prescription for an 80-year-old debilitated,
dysvascular, diabetic transfemoral amputee?
(a) Single axis
(b) Polycentric
(c) Pneumatic
(d) Manual locking
(d) A manual-locking knee is indicated for new unstable amputees and those who need utmost stability
because of muscular weakness or poor coordination. The other components are generally used in
persons with less risk of falling.
- When applying a static resting hand splint to a person who had a stroke with upper limb paralysis,
what is the appropriate joint position to maintain the hand in a functional position?
(a) 20° of wrist flexion
(b) 90° of metacarpophalangeal flexion
(c) Neutral position or slight flexion of the distal interphalangeal joints
(d) 30° of thumb opposition across the palm
(c) A resting hand splint is designed to maintain a position of function in a hand that is weak or
paralyzed. It is applied on the volar surface and extends from the fingertips to the proximal third of
the forearm. The wrist is typically placed in slight extension. The metacarpophalangeal joints are
placed in slight flexion and the interphalangeal joints are placed in a neutral position or in slight
flexion. The thumb is supported in a position between palmar and radial abduction.
- How does a weighted kypho-orthosis (Posture Training Support®) improve function in patients
with chronic thoracic kyphosis?
(a) Improves posture
(b) Strengthens spinal extensors
(c) Promotes bone formation
(d) Helps activate rectus abdominus
(a) A weighted kypho-orthosis improves posture without any effect on pain.
- A person with diabetes presents with an area of nonblanching erythema on the plantar surface of
the foot at the first metatarsal head. Recommendations for footwear would include
(a) custom-molded shoe insert.
(b) narrow toe box shoe.
(c) heel lift on the affected side.
(d) calcaneal bar added to the sole of the shoe.
(a) Footwear for the person with diabetes and grade 1 skin changes on the plantar aspect of the foot
should be designed to relieve pressure over the affected site while evenly distributing pressure over
the remaining foot surface to prevent other skin breakdown. A typical prescription would include an
extra-depth shoe with a wide toebox and a total-contact, custom-molded insert with pressure relief
at the area of skin irritation. Further shoe modifications with a metatarsal bar and rocker bottom
sole could also be considered, especially if the patient had grade 2 skin changes or more severe foot
deformities. A calcaneal bar or heel lift would not be appropriate considerations in this case.
- What type of prehension is provided by a wrist-driven tenodesis orthosis?
(a) Lateral
(b) 3-jaw chuck
(c) Cylindrical
(d) Tip-to-tip
(b) The wrist-driven tenodesis hinge orthosis creates a 3-jaw chuck prehension by stabilizing the
interphalangeal joints of digits 2 and 3 and the interphalangeal and metacarpophalangeal joints of
the thumb. The extensor carpi radialis muscle activates the wrist extension, which through tenodesis
action creates a 3-jaw chuck prehension.
- In adult patients, what advantage does a knee disarticulation amputation have over a transfemoral
amputation?
(a) Better cosmetic appearance with prosthetic fitting
(b) Reduced risk of phantom pain
(c) Increased ability to bear weight on the distal residual limb
(d) Improved surgical wound healing
(c) Compared with a transfemoral level amputation, a knee disarticulation provides increased ability to
bear weight on the distal residual limb. There is no evidence that knee disarticulation amputations
have a reduced risk of phantom pain or have improved surgical wound healing. Amputations at the
transfemoral level typically have a better cosmetic appearance with prosthetic fittings because the
distal prosthetic socket can be tapered to be more symmetric with the opposite side. Knee
disarticulation amputations also have a prosthetic knee axis of rotation that is distal compared to the
intact knee.
- The proper static alignment of the socket in a transtibial prosthesis will place the socket in slight
(a) flexion.
(b) extension.
(c) external rotation.
(d) abduction.
(a) The socket of a transtibial prosthesis is typically slightly flexed during the static prosthesis
alignment process. Proper flexion of the socket improves weight-bearing characteristics and also
reduces knee extension forces during mid-stance and the terminal stance phases of gait. The static
alignment also places the socket in 5° of adduction with the foot slightly inset relative to the socket.
- A 30-year-old man who is otherwise healthy presents following traumatic bilateral transfemoral
amputations. Based on your understanding of the increased metabolic demands associated with
prosthetic ambulation, you conclude that
(a) he should not be considered a prosthetic candidate.
(b) he will have reduced ability to ambulate for long distances
(c) cardiac stress testing is recommended prior to consideration for prosthetic fitting.
(d) he will be able to use prosthetic devices for transfers and standing activities only.
(b) The metabolic cost of ambulation (mL oxygen consumed per body weight per meter) is a measure
of energy consumption per distance. The metabolic cost of ambulation increases following a lower
limb amputation and the amount of increase is related to the level of the amputation as well as the
amputation’s etiology. Because of this increased metabolic cost, persons will have reduced
endurance for ambulation following an amputation. This would be especially true for an individual
with bilateral transfemoral amputation(s). The person described, however, should be considered a
candidate for prosthetic ambulation and, since he has no prior cardiac history or significant risk
factors, cardiac stress testing would not be indicated.
- A 60-year-old woman is being discharged to home from your rehabilitation unit following a right
middle cerebral artery ischemic stroke with resultant left hemiparesis. She is ambulatory for short
household distances with the use of a hemiwalker on the right. Recommendations for a manual
wheelchair for this patient would include
(a) hemi-height, with removable swing-away leg rests.
(b) hemi-height, with nonremovable swing-away leg rests.
(c) standard-height, with removable swing-away leg rests.
(d) standard-height, with nonremovable swing-away leg rests.
(a) Wheelchair recommendations for a person with hemiparesis and limited ambulatory abilities would
include a hemi-height chair which is lower to the ground than to a standard height wheelchair. This
configuration provides the patient greater advantage to propel the wheelchair with the unaffected
lower extremity. It is also important for the leg rests to be removable so that they do not interfere
with the patient’s ability to propel the wheelchair.
- What is the average range of motion at the ankle during normal human ambulation over a level
surface?
(a) 0° dorsiflexion, 10° plantarflexion
(b) 30° dorsiflexion, 20° plantarflexion
(c) 5° dorsiflexion, 20° plantarflexion
(d) 10° dorsiflexion, 10° plantarflexion
(c) The average range of motion at the ankle during normal human ambulation over level surfaces is
from 5° of dorsiflexion to 20° of plantarflexion. This range of motion varies with ambulation over
uneven surfaces and with activities such as stair climbing.
- An elderly patient with breast cancer and widespread osseous metastases has developed acute onset,
severe low thoracic back pain while stooping forward to lift groceries. In addition to formulating a
pain management program and initiating bisphosphonate therapy, what brace do you prescribe for
this patient?
(a) Jewett
(b) Knight-Taylor
(c) Williams
(d) Chairback
(a) The patient has developed a vertebral compression fracture. An extension brace will minimize her
pain and possibly reduce further pathological compression fractures. The Knight-Taylor brace
provides thoracolumbar spine control in the saggital and coronal planes. The Williams brace is a
lumbosacral extension-lateral control orthotic. The chairback brace is an example of a lumbosacral
flexion-extension control orthosis.
- What is the best-established benefit of a microprocessor-controlled knee unit, compared to a
conventional pneumatic knee unit?
(a) It provides both swing and stance phase control.
(b) It allows greater knee flexion to perform bending and lifting activities.
(c) It allows running at faster speeds.
(d) It provides a more natural and symmetric gait pattern.
(d) Microprocessor controlled knee units use a computerized system to automatically adjust the knee
unit’s resistance over a wide range of gait speeds. With this automatic control, there is greater
consistency and reliability in the knee movement during the gait cycle. These benefits give the
amputee greater confidence and improve swing phase responsiveness and gait symmetry, as well.
Negative aspects of the microprocessor controlled knee units are heavier weight and greater
expense. These units have not been shown to improve running speed.
- Regarding energy expenditure during prosthetic ambulation,
(a) at self selected walking speeds, someone ambulating with a transtibial prosthesis has a higher
rate of metabolic energy expenditure [mlO2/(kg•meter)] compared with normal human
locomotion.
(b) whether a person has a transtibial or transfemoral prosthesis, the metabolic cost
[mlO2/(kg•meter)] of ambulation is the same.
(c) at self selected walking speeds, cardiac work load during transtibial prosthetic ambulation is
comparable to that in normal human locomotion.
(d) gait velocity [meters/min] during transtibial prosthetic ambulation is comparable to that in
transfemoral prosthetic ambulation.
(c) The rate of metabolic energy expenditure–mlO2/(kg•minute)–represents energy expenditure per unitof time in comparison to metabolic cost–mlO2/(kg•minute)–which is a measure of energyexpenditure per unit distance, a meter. The metabolic cost of prosthetic ambulation is greater thanthat used in normal human locomotion and the metabolic cost of transfemoral prosthetic ambulationis greater than that in transtibial prosthetic ambulation. Because individuals who ambulate withaprosthesis slow their gait velocity, their rate of metabolic energy expenditure is relativelyunchanged compared to normal ambulation at self-selected walking speeds. Because the rate ofmetabolic energy expenditure is maintained at a level comparable to ambulation without aprosthesis, cardiac work load is also unchanged during ambulation with either a transtibial ortransfemoral prosthesis, if subjects are allowed to walk at their self-selected walking speed.
- What is the rationale for bracing for low back pain in the injured worker?
(a) It has been shown to prevent further low back pain injury.
(b) It prevents further injury and should be used in all injuries occurring at work.
(c) It has been shown to improve lifting capabilities.
(d) It can provide proprioceptive feedback to reinforce proper mechanics.
(d) Lumbar supports do not prophylactically prevent low back injuries or prevent recurrence of low
back pain. One study showed a decrease in lost time at work when lumbar supports were utilized
with a back injury educational program. No improvement in lifting capacity has been found with
the use of bracing. Workers who use lumbar supports use them as a proprioceptive reminder to use
proper mechanics with lifting and other work-related activities.
- Which circumstance is most likely to result in left knee hyperextension at initial contact (heel strike)
in a patient with spastic left hemiparesis?
(a) Solid ankle, double-metal, upright ankle-foot orthosis set in 5° of plantar flexion
(b) Addition of a solid one-quarter inch heel to the left shoe
(c) Addition of ankle dorsiflexion spring assistance to a dual-channel, double-metal, ankle-foot
orthosis
(d) Addition of a T-bar strap to a double-metal upright ankle-foot orthosis to reduce foot inversion
(a) Placing a solid ankle, double-metal, upright ankle-foot orthosis in 5° of plantarflexion will increase
the extension moment (forces) at the knee and this can result in knee hyperextension, especially at
the time of initial contact (heel strike). Addition of a T-bar strap should not effect the knee and the
addition of dorsiflexion spring assistance or a one-quarter inch heel will reduce the tendency to
have knee hyperextension.
- Which spinal orthosis is used to prevent thoracic spinal flexion by providing 3-point pressure over
the sternum and pubis anteriorly and the upper lumbar spine posteriorly?
(a) Custom molded, plastic thoracolumbosacral orthosis
(b) Lumbosacral corset with posterior metal stays
(c) Jewett orthosis
(d) Taylor orthosis
(c) Several different types of thoracolumbosacral (TLSO) orthoses are available to control segmental
spine motion in this region. A custom molded plastic TLSO provides almost total contact support
for uniform pressure distribution and control of motion in all plains. A lumbosacral corset with
metal stays provides support circumferentially and helps reduce spine motion primarily in the
lumbosacral region. A Taylor orthosis also provides circumferential support with the addition of
axillary straps. The Taylor orthosis is primarily designed to resist flexion and extension. A Jewett
brace is designed to limit thoracic spine flexion by providing 3-point pressure over the sterum and
pubis anteriorally and the upper lumbar spine posteriorally. This type of brace is used most
commonly for individuals with thoracic spine anterior compression fractures.
At which location is a Syme amputation performed?
(a) through distal end of tibia and fibula
(b) coronally through the calcaneus
(c) just distal to talus and calcaneus
(d) tarsal metatarsal disarticulation (proximal to metatarsals)
(a) A Syme amputation (A) is ankle disarticulation with tapering of the medial and lateral malleoli and
preservation of the heel pad for soft tissue coverage and distal weight bearing. A Boyd hindfoot (B)
amputation is a talectomy and calcaneal-tibial arthrodesis after forward translation of the calcaneus.
A Chopart level (C) amputation is performed at the mid-tarsal level with sparing of the talus and
calcaneus. A tarsal-metatarsal disarticulation (D) is also referred to as a Lisfranc amputation.
- In an upper-extremity prosthesis, an advantage of a voluntary-closing hook terminal device that a
voluntary-opening device does not have is
(a) the ability to carry objects with less fatigue.
(b) improved ability to manipulate fragile objects.
(c) an adjustable pinch force effected by changing the number of elastic bands.
(d) a better ability to visualize the object being manipulated.
(b) One advantage of a voluntary-closing hook terminal device is the ability to adjust the amount of
pinch force by adjusting pressure on the cable control. This improves the ability to manipulate
fragile objects. A voluntary opening terminal device uses elastic bands to determine the pinch force
and the number of bands would have to be reduced to decrease the pinch force. When carrying
objects, voluntary-closing terminal devices require constant cable tension and this can result in
quicker fatigue. The ability to visualize the object being manipulated would not be dependent upon
whether the terminal device is voluntary closing or voluntary opening.
- What is the primary motion used to open a voluntary-opening terminal device in a body-powered
transradial prosthesis?
(a) Glenohumeral flexion
(b) Glenohumeral extension
(c) Biscapular elevation
(d) Biscapular adduction
(a) The control cable for opening the terminal device of a standard transradial prosthesis using a
voluntary-opening terminal device passes posterior to the elbow joint, along the posterior arm, and
attaches to the posterior support strap of a figure-of-8 harness. This arrangement allows
glenohumoral flexion to produce tension in the cable and open the terminal device. Glenohumoral
extension and biscapular adduction decrease tension on the control cable. Biscapular elevation
would not produce cable tension required for terminal device operation.
- Regarding acquired upper extremity amputation in adults,
(a) the most common level is transhumeral.
(b) they account for approximately 50% of all acquired major limb amputations.
(c) they are most common in the 20- to 40-year-old age group.
(d) their most common cause is malignancy.
(c) Trauma is the most common cause of upper extremity amputation in adults. Malignancy is a more
common cause of amputation in the pediatric population. Upper extremity amputations occur most
commonly in the 20- to 40-year-old age group, as a result of trauma and work related accidents.
The dominant extremity is affected more commonly and amputations at the transradial level are the
most common level of upper extremity amputation. Upper extremity amputations occur much less
frequently than lower extremity amputations. Upper extremity amputations account for
approximately 20% of all major limb amputations.
- A 37-year-old woman with polymyositis complains of difficulty walking and occasional falling. On
physical examination, she has muscle strength: iliopsoas 2/5, gluteus maximus 4/5, quadriceps 4+/5,
hamstrings 3+/5, anterior tibialis 4/5, gastrocnemius/soleus 4/5. Range of motion is normal. You
would prescribe
(a) bilateral forearm crutches.
(b) knee-ankle-foot orthoses.
(c) reciprocal gait orthosis.
(d) standard adult walker.
(a) The patient’s main weakness is proximal and she has sufficient ankle dorsiflexion and knee
extension strength. Hence she would not benefit just with knee-ankle-foot orthoses. Reciprocal
gait orthoses are designed to help children with active hip flexion but no hip extension.
Furthermore, both these options would be too bulky for such a patient to handle efficiently. A
standard walker would result in a bent forward posture and would limit the patient’s gait speed.
Forearm crutches would allow a more upright posture and an alternate 2-point gait or a 4-point gait.
- One advantage of a small diameter caster (front wheelchair wheel) is
(a) greater ability to traverse rough terrain.
(b) better stability on steep inclines.
(c) less frequent maintenance.
(d) greater maneuverability.
(d) Small diameter casters on a wheelchair reduce the chair’s turning radius, which gives it greater
maneuverability. These casters frequently are mounted on wheelchairs used for sports such as
basketball. Smaller diameter casters are less well suited for outdoor activities over rough terrain.
The size of the caster does not affect the maintenance required and does not improve wheelchair
stability on inclines. Hard, narrow casters are typically recommended for mobility over smooth,
level surfaces whereas wider, larger casters are better for mobility over uneven, rough surfaces.
- Which shoe modification would NOT be appropriate for an individual with loss of protective
sensation on the foot secondary to diabetes?
(a) Wide toe box
(b) Rocker bottom
(c) Soft inner shoe liner
(d) Solid steel shank
(d) All of the shoe modifications listed would be appropriate for an individual with loss of protective
sensation except for the use of a solid steel shank built into the sole of the shoe. This modification
would decrease the accommodative properties of the shoe and may increase the potential for skin
breakdown.
- In which case would a wrist-hand-finger orthosis utilizing dynamic metacarpophalangeal extension
assistance be most indicated?
(a) Complete radial nerve injury at the level of the mid-humerus
(b) Partial ulnar nerve injury at the level of the elbow
(c) Complete median nerve injury in the forearm
(d) C5 level ASIA class A spinal cord injury
(a) With a radial nerve injury at the level described, there is loss of wrist and metacarpal extension
because of denervation of the forearm extensor muscles. A dorsal wrist-hand-finger orthosis that
holds the wrist, fingers, and thumb in extension and permits flexion of the digits with a low-profile
outrigger is used to substitute for this loss of function. This type of orthosis would be inappropriate
for the other conditions described.
- A patient is referred to your office by his primary care physician for evaluation of an unusual gait
pattern caused by a remote case of polio. You note excessive lateral trunk flexion to the left during
stance phase between foot flat and heel off. Swing phase is normal. On exam there is normal hip
flexor strength bilaterally. The gluteus medius is 4-/5 on the left and 5/5 on the right. Knee strength
is normal. The tibialis anterior is 4-/5 on the right and 5-/5 on the left. Range of motion is normal at
all joints. Which gait abnormality is occurring?
(a) Waddling gait
(b) Steppage gait
(c) Trendelenberg gait
(d) Circumducted gait
(c) A waddling gait occurs when there is bilateral gluteus medius weakness. A steppage gait occurs as
an abnormality in swing phase due to severely weak dorsiflexors of the ankle. Foot slap is seen with
moderately weak dorsiflexors and occurs on the side of weakness. Trendelenberg gait is excessive
lateral flexion due to ipsilateral weakness. Circumduction is the swinging of the limb in a wide
lateral arc.
- A patient ambulates with a Trendelenburg gait. You suspect an injury to the
(a) femoral nerve.
(b) superior gluteal nerve.
(c) obturator nerve.
(d) sciatic nerve.
(b) Trendelenburg gait is characterized by excessive dropping of the pelvis contralateral to the stancephase
leg. It is caused by weakness of the hip abductors, which include the gluteus medius
innervated by the superior gluteal nerve.
- Which form of prosthetic suspension is NOT utilized with the transhumeral amputation?
(a) Harness
(b) Self-suspension
(c) Suction
(d) Joint and corset
(d) Traditional suspension systems include harness (figure-of-8 or -9, chest strap, and shoulder saddle),
self-suspension (condylar, Muenster, or Northwestern), semisuction (semisuction or hypobaric) and
suction (full suction or silicone sock).
- The best example of a dynamic orthosis is
(a) dorsal wrist hand orthosis with extension force in radial nerve injury.
(b) thermoplastic ankle foot orthosis in severe foot drop.
(c) wrist hand orthosis in 15° of extension for carpal tunnel syndrome.
(d) a C-bar in median nerve injury.
(a) Static means that the orthosis is rigid and gives support without allowing movement. These devices
are commonly used to rest a part after trauma or surgery, and for acutely inflamed joints and
tendons. Dynamic orthoses allow a certain degree of movement. They usually provide some
element of assisted motion to the joint, such as the elastic assist to wrist extension in the orthosis for
radial nerve palsy.
- On hospital rounds, you note that your patient, who has a T10ASIA B spinal cord injury is now
using a rigid frame wheelchair in the therapy gym. In his attempt to show off as he propels toward
you, he suddenly flips over backward. What is the most likely problem?
(a) The rear axles are located directly under his center of gravity.
(b) The rolling resistance is increased.
(c) There is too much caster flutter.
(d) There is asymmetry in the chair’s camber angle from side to side.
(a) The center of gravity for a hypothetical wheelchair rider is typically located slightly forward of the
rear axle. Moving the rear axle directly under the wheelchair user makes the person and the chair
more likely to flip backwards (wheelie). However, the advantages to having the center of gravity
near the rear axles include decreased tendency for caster flutter, decreased rolling resistance, since
most of the weight is borne by the larger rear wheels, and minimization of the turning torque.
- Which of the following is true regarding skeletal design of a lower extremity prosthesis?
(a) Endoskeletal tends to weigh less.
(b) Exoskeletal is less hardy.
(c) Endoskeletal tends to demand less maintenance.
(d) Exoskeletal is easily adjusted after fabrication.
(a) Exoskeletal designs tend to weigh more, are more rugged, demand less maintenance, and cannot be
adjusted after fabrication. Generally, the opposite is true of endoskeletal designs.
- A patient presents for evaluation of his new ankle-foot orthosis (AFO). During ambulation you
notice that he has reduced hip extension and stride length, and a slowed gait. At the initiation of
stance phase, heel strike is not consistently present. You conclude that the abnormal gait is due to
excessive
(a) knee extension at heel strike and recommend setting the AFO in greater dorsiflexion.
(b) hip flexion contracture and recommend setting the AFO in greater dorsiflexion.
(c) knee flexion at heel strike and recommend setting the AFO in greater plantar flexion.
(d) dorsiflexion of the ankle and recommend setting the AFO in plantar flexion.
(b) Excessive knee extension at heel strike is frequently seen with hamstring weakness or
gastrocnemius muscle spasticity. It causes the patient to walk on the heel, with external rotation of
the leg and no knee flexion at heel strike. Excessive knee flexion at heel strike is frequently seen
with an ankle-foot orthosis (AFO) that is set in too much dorsiflexion. This setting causes the midstance
period to be reduced and the push-off effect diminished, causing the knee to be excessively
flexed and thereby slowing the gait. If the tip of the shoe on the AFO side is raised too high at heel
strike, the AFO is set in too much dorsiflexion. Only answer b addresses all of the abnormalities
seen in this individual.
- In a person with complete paraplegia, which gait has the highest energy expenditure per meter?
(a) Swing-through gait in standard knee-ankle-foot orthoses
(b) Swing-through gait in Scott-Craig knee-ankle-foot orthoses
(c) Reciprocating gait in a reciprocating gait orthosis
(d) Swing-to gait using a standard walker
(c) Energy expenditure in paraplegia is as follows (in order of lowest to highest): normal walking,
swing-through gait in a Scott-Craig knee-ankle-foot orthosis (KAFO), swing-through gait in a
standard KAFO, reciprocating gait in a reciprocating gait orthosis. Swing-through gait in a
reciprocating gait orthosis requires approximately the same energy expenditure as the Scott-Craig
KAFO.
- In a metal ankle joint (double action joint or Klenzak ankle joint) used in ankle-foot orthoses, which
component assists dorsiflexion?
(a) Anterior spring
(b) Anterior rod
(c) Posterior spring
(d) Posterior rod
(c) An anterior spring assists plantar flexion and has no specific clinical indications. An anterior rod
limits dorsiflexion and is used for weak plantar flexors, weak knee extensors, and pain with ankle
motion. A posterior spring assists dorsiflexion and is used for flaccid footdrop and knee
hyperextension. A posterior rod limits plantar flexion and is used for plantar spasticity, toe drag,
and pain with ankle motion.
- A balanced forearm orthosis is indicated for patients with weakness in which muscle-group
combination?
(a) Deltoid and elbow flexors
(b) Deltoid and triceps
(c) Pectoralis group and pronators
(d) Pectoralis group and triceps
(a) A balanced forearm orthosis can be attached to a wheelchair. It consists of a forearm trough, which
is attached by a hinge joint to a ball-bearing swivel mechanism and a mount. It supports the weight
of the forearm and arm against gravity. With only minimal muscle force requirement at the
shoulder girdle and trunk, the patient can move the arm horizontally and flex the elbow to bring the
hand to the mouth. This orthosis is primarily used for patients with severe upper limb weakness
(especially the deltoid and elbow flexors), as in high quadriplegia or other severe neuromuscular
conditions. The patient must also have sufficient range of motion of the shoulder and elbow, as well
as adequate trunk stability (provided or innate) while sitting.
- Which of the following orthoses or shoe modifications is used in the conservative management of
plantar fasciitis?
(a) Heel lift
(b) Posterior night splint
(c) Lateral heel wedge
(d) Metatarsal bar
(b) A heel lift plantarflexes the foot and is used for Achilles tendinitis. A metatarsal bar is used for
metatarsalgia. A lateral heel wedge can be used for the conservative management of osteoarthritis
of the knee. A posterior night splint dorsiflexed to 5/ is the correct answer.
- During normal human locomotion, the center of gravity travels through a sinusoidal pathway that is
modified by 6 determinants of gait. Which of the following is not considered 1 of the 6
determinants?
(a) Pelvic extension
(b) Foot and ankle synchronization
(c) Knee flexion
(d) Lateral pelvic displacement
(a) The 6 determinants are as follows: lateral displacement that reduces horizontal excursion from 6”
down to 1.7”; knee flexion that reduces vertical excursion 7/16”; pelvic rotation that reduces
vertical excursion 3/8”; pelvic tilt that reduces vertical excursion 3/16”; and foot and ankle
synchronization as well as ankle and knee synchronization that both serve to smooth out the
sinusoidal curve but do not decrease excursion.
- A 79-year-old cachetic woman with coronary artery disease and unstable angina sustains a right hip
fracture after a fall. After an open-reduction internal fixation of the hip joint with the use of a
dynamic hip screw, the orthopedic surgeon determines that the patient is 25% partial weight
bearing to the right side. She has weak upper body strength and good balance. Which of the
following assistive devices is most appropriate?
(a) Standard walker
(b) Rolling walker
(c) Axillary crutches
(d) Quad cane
(b) Standard walkers require good standing balance and good upper body strength. Crutches require
good upper body strength and have an increased energy expenditure of 40%-60%, which would be
contraindicated in unstable angina. Quad canes are not appropriate when significant weight-bearing
relief is required. Rolling walkers are most appropriate for patients who lack upper body strength
and provide safer gait than crutches or canes.
- Which one of the following cervical orthoses is the most restrictive to range of motion in flexion,
extension, axial rotation, and lateral bending, both actively and passively?
(a) Soft collar
(b) Philadelphia collar
(c) Philadelphia collar with thoracic extension
(d) Sternal-occipital-mandibular immobilizer collar
(d) Measurements of the range of motion in flexion, extension, axial rotation, and lateral bending (both
actively and passively) using a computerized motion analyzer for four orthoses—soft collar,
Philadelphia collar, Philadelphia collar with thoracic extension, and a Sternal-occipital-mandibular
immobilizer (SOMI)—found that the SOMI was most restrictive.
- What level of amputation has the highest acceptance rate for an upper extremity prosthesis?
(a) Wrist disarticulation
(b) Transradial
(c) Elbow disarticulation
(d) Transhumeral
(b) Overall rejection of prosthetic usage occurs in 33%-38% of unilateral upper extremity amputees.
The highest acceptance rate is transradial at about 93%, and the lowest is wrist disarticulation at
about 6%.
- When considering realistic functional goals for the majority of transhumeral amputees, the
maximal weight (in pounds) that can be carried with the body-powered prosthesis is
(a) 7.
(b) 15.
(c) 30.
(d) 50.
(b) Handling of heavy objects is limited in upper extremity amputees. A transhumeral amputee is
expected to lift 10lb to 15lb, unless the residual limb is very short or sensitive. A transradial
amputee is expected to lift 20lb to 30lb unless the residual limb is very short or sensitive.
- When comparing quadrilateral sockets with ischial containment sockets, a successful fitting is
more likely in a quadrilateral socket when
(a) the adductor musculature is intact.
(b) the residual limb is fleshy.
(c) trunk stability demands are high at mid stance.
(d) the residual limb is shorter.
(a) Chances of a successful fitting of a quadrilateral socket are best when the residual limb is longer
with a firm residuum and intact adductor musculature. Ischial containment sockets are more
successful than quadrilateral sockets for persons with shorter, fleshy, unstable residual limbs.
- In a patient with bilateral hip flexion contractures, which of the following gait deviations would be
most likely?
(a) Bilateral Trendelenburg gait
(b) Early heel rise during stance
(c) Swing-phase circumduction
(d) Increased knee flexion in stance
(d) In normal gait, hip extension to neutral occurs during stance phase. When mild hip flexion
contractures are present, a compensatory increase in lumbar lordosis occurs to maintain upright
trunk posture. As the extent of the hip flexion contractures worsens, there is usually an additional
compensatory increase in knee flexion during stance phase.
- Which of the following knee types provides good stability in early stance phase and ease of flexion
while weight bearing during the pre-swing phase (terminal stance) of the gait cycle?
(a) Single axis
(b) Stance phase control
(c) Polycentric
(d) Manual locking
(c) Many polycentric knees are designed so that the center of rotation moves anteriorly very rapidly
during the first few degrees of knee flexion, quickly passing in front of the floor reaction line and
facilitating the swing phase. Because the polycentric knee can be flexed under weight bearing
during the terminal stance, when properly dynamically aligned it can offer both excellent stance
stability and ease of swing-phase flexion. Furthermore, all polycentric knees shorten mechanically
to a slight degree during flexion, adding additional toe clearance during midswing.
- An amputee presents for evaluation of distal blistering and evidence of vascular congestion. You
diagnose choke syndrome. Which of the following would NOT be an acceptable treatment for
choke syndrome?
(a) Expanding the proximal socket
(b) Increasing the auxiliary suspension to decrease vertical pull
(c) Relieving the distal socket where it interfaces with the choked surface
(d) Padding the distal socket where it corresponds to the choked surface
(c) The choke syndrome (proximal soft tissue constriction leading to vascular congestion) may occur
with suction sockets or self-suspending systems. Relieving the proximal socket to allow vascular
return, providing auxiliary suspension to decrease the vertical pull on the residual limb, and
improving the intimacy of the socket-limb interface correct this problem. Relieving the distal
socket where it interfaces with the choked surface would increase the vacuum effect in this area
and thereby increase the choke phenomenon.
- A wrist-hand orthosis used as symptomatic management for carpal tunnel syndrome should be
(a) limited to patients with short-duration symptoms.
(b) worn only during the day.
(c) worn with the wrist in neutral position.
(d) worn with the wrist in 30( of extension.
(c) A neutral position of a wrist-hand orthosis unloads the median nerve; wrist extension will
aggravate nerve compression.
- Which of the following shoe components distinguishes a blucher-style shoe from a bal-style shoe?
(a) Throat
(b) Toe box
(c) Heel
(d) Vamp
(a) There are two shoe types, the blucher and the bal. The components of a blucher shoe include the
tongue, lace stay, open throat, toe box, toe spring, vamp, ball, shank, breast, quarter, and heel. The
major difference with a bal style is that the throat is closed, limiting the ability of the shoe to open
and accommodate an orthosis. For this reason, a blucher is the style of dress shoe most often
recommended to patients who require an orthosis.
- A 35-year-old man experiences a severe S1 radiculopathy. As a result, he loses essentially all
strength within the posterior compartment of the leg. It is 6 months later, and you are consulted to
provide an orthosis to aid his ambulation. The best recommendation would be
(a) a posterior leaf spring ankle-foot orthosis (AFO).
(b) an articulating AFO with plantar flexion stop.
(c) an articulating AFO with dorsiflexion stop.
(d) an articulating AFO with dorsiflexion assist.
(c) In this condition, lack of active plantar flexion occurs, heel-rise is delayed, the mid-stance phase is
prolonged, and push-off force is reduced. A dorsiflexion stop can accommodate for this weakness.
Setting the stop at 5° of dorsiflexion substitutes best for gastrocnemius function.
- A 75-year-old woman falls and fractures her distal humerus. In the process, the ulnar nerve is
damaged. She presents 6 months later with weakness in the fourth and fifth digits, claw deformity,
and loss of grip power. Which of the following orthotic components could benefit this patient and,
therefore, should be included in the orthotic prescription?
(a) Dorsal outrigger
(b) C bar
(c) Lumbrical bar
(d) Opponens bar
(c) A dorsal metacarpophalangeal extension stop (also called a lumbrical bar) to the fourth and fifth
digits is usually quite effective at preventing hyperextension of the fourth and fifth
metacarpophalangeal joints. This permits the proper wrapping of the fingers around an object and
thus allows a stronger grip.
