P & O Flashcards
Most common cause of upper limb amputations?
Trauma
Most common cause of lower limb amputations?
Dysvascular disease (PVD, DMT2, factor V Leiden)
Most common suspension system for upper extremity prosthesis?
Figure 8 harness
Strap loops around contralateral axilla - acts as counterforce for cable-control action of terminal device
Potential complications if residual limb doesn’t have total contact w/ socket?
Venous choke points –> verrucous hyperplasia, skin breakdown
Exceptions can be made for sensitive areas requiring window cutouts (bony overgrowth, neuroma, skin breakdown sites)
Special wrist consideration for b/l UE amputee?
One extremity should have a prosthesis w/ wrist rotation and flexion device that permits access to body midline
Most common body-powered terminal device for UE amputee?
Three jaw chuck
Most common set-up for three-jaw chuck body-powered terminal device? (voluntary opening vs. voluntary closing)
Voluntary opening
Terminal device remains closed at rest
Motion required to flex a prosthetic elbow using a dual-cable control system?
Biscapular abduction and humeral depression to flex elbow
Motion required to lock a prosthetic elbow using a dual-cable control system?
biscapular depression and humeral extension to lock the elbow in place
What muscles are used to control a myoelectric below-elbow prosthesis?
wrist flexors and extensors
Which myoelectric controller setup is preferred for very young children?
One-site, one-function controller (also used if amputee does not have two good myoelectric sites)
two-site, two-function = electrodes placed on two antagonist muscles to open and close the terminal device
one-site, two function (“double channel”), uses signals from one muscle to control both opening and closing terminal device (i.e. weak contraction closes, strong contraction opens)
Prosthesis for forequarter amputation?
usually passive prosthesis for cosmetic purposes, as prosthesis is challenging to operate/requires special attention towards an acceptable suspension system
Forequarter usually performed due to cancer (includes clavicle and scapula)
Consideration w/ transhumeral amputation length?
Longer residual limb is better for patient function
Benefits of elbow disarticulation vs. transhumeral amputation?
Surgery is easier, less bloody, functionally = better residual limb than transhumeral
Most common congenital limb defect?
Left Transradial defect
Consideration w/ transradial amputation length?
The longer the residual limb, the more supination/pronation is preserved
Ideal residual limb shape for transfemoral amputation?
conical
Ideal residual limb shape for transtibial amputation?
Cylindrical
Optimal spot to amputate for transtibial amputation is where?
Within the proximal 50% of the tibia
What is the difference b/t myoplasty and myodesis?
Myoplasty: muscles are sutured together (easier surgery)
Myodesis: muscles are sutured into the bone (more stable surgical result) *not suitable in severe dysvascular patients as will not heal properly)
Difference b/t a Boyd and Pirigoff amputation?
Boyd = horizontal calcaneal amputation
Pirigoff = vertical calcaneal amputation
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K Level?
Nonambulatory, may need prosthesis to aid in transfers
K0
K Level?
Limited household ambulator, fixed cadence
K1
K Level?
Unlimited household ambulator; limited community ambulator; fixed cadence
K2
K Level?
Unlimited community ambulator, variable cadence
K3
K Level?
High impact activities; sports; variable cadence
K4
Increased ambulation energy expenditure for traumatic unilateral transtibial amputee?
20%
Increased ambulation energy expenditure for traumatic bilateral transtibial amputee?
40%
Increased ambulation energy expenditure for traumatic unilateral transfemoral amputee?
60%
Increased ambulation energy expenditure for traumatic b/l transfemoral amputee?
200%
Increased ambulation energy expenditure for dysvascular unilateral transtibial amputee?
40%
Increased ambulation energy expenditure for dysvascular b/l transtibial amputee?
80%
Increased ambulation energy expenditure for dysvascular unilateral transfemoral amputee?
120%
Increased ambulation energy expenditure for dysvascular b/l transfemoral amputee?
400%
Preferred socket design for transfemoral prosthesis?
ischial containment socket
Maintains a little thigh adduction and flexion to place the abductors and extensors in a mechanically advantageous stretched position
Which transfemoral prosthetic socket is narrow AP, and wide medial-lateral?
Quadrilateral socket
What are pressure tolerant areas for transtibial prostheses?
patellar tendon
medial tibial flare
medial tibial shaft
anterior tibial muscles
Fibular shaft
Popliteal fossa
Socket adjustment if venous choking is occuring?
adjust number of sock ply worn by the patient or fabricate new socket
Venous chocking occurs when socket is too tight, distal limb hangs in place without contacting socket wall, choking distal venous return
Cause of transfemoral gait abnormality?
Abducted, circumducted gait, or vaulting on prosthetic side?
Prosthesis too long
Inappropriate sizing of socket walls providing discomfort
abduction contracture
patient does not trust knee to bend properly and stabilize them
Poor suspension
Knee unit not flexing properly
Cause of transtibial gait abnormality?
Excessive varus moment
Foot is set too far medially
Socket is too abducted
Cause of transtibial gait abnormality?
Excessive valgus moment
Foot is set too far laterally
Socket is too adducted
Cause of transtibial gait abnormality?
Excessive knee flexion
Not enough friction built into knee unit
Too much dorsiflexion in foot
Weak quads
Socket placed too far anteriorly
Foot placed too posteriorly, knee flexion contracture
Cause of transtibial gait abnormality?
Excessive knee extension
Too much friction built into knee unit
Too much plantarflexion in the foot
Weak quads (recurvatum)
Socket placed too far posteriorly
Foot placed too far anteriorly
When should a child be fit w/ upper extremity prosthethsis
approx 6 months (when sitting w/ support)
“fit to sit”
When should a child be fit w/ lower extremity prosthesis?
approx 12 months (or sooner, when pulling to stand)
What is the most common complication in a pediatric amputee whose growth plates have not yet fused?
terminal overgrowth
Most frequently a problem in transtibial amputations (can occur in both acquired and congenital amputations)
What principle of orthotics achieves stable manipulation of a joint?
3-point pressure principle
Most restrictive cervical spinal orthosis?
Halo vest
Used in unstable C-spine fractures (such as type 2 dens fracture); bolted to skull w/ 4 pins (invasive, risk for infection)
None-invasive alternative to Halo vest that can be used for unstable cervical fractures?
Minerva Jacket
large, cumbersome, unappealing, stiff jacket
Is a Sterno-Occipital Mandibular Immobilizer (SOMI) more or less restrictive than a rigid Cervical collar?
More restrictive
Uses bars that connect to one another from the sternum, occiput, and mandible to limit ROM
Used for STABLE C-spine fractures; can be donned supine
Which planes of motion are best restricted by the rigid cervical collars (Philadelphia, Aspen, Miami J, etc)?
immobilize both flexion and extension at C5-C6 (especially with thoracic extension
*Does not control lateral bending and axial rotation at C2-3 and C3-4
Used for STABLE cervical fractures
Complications/risks of use of soft cervical collars?
Atrophy of neck muscles
Soft foam collars do not restrict motion, simply provide kinesthetic reminder - patient preference
Orthoses indicated for vertebral body compression fractures/stable burst fractures?
Jewett Brace or CASH (cruciform anterior spinal hyperextension orthosis) brace
Prevent hyperflexion of the thoracolumbar spine
*CASH brace is less cumbersome
Function of TSLOs in terms of “bracing the core”?
Increase intraabdominal pressure, which allows forces to be transmitted into the abdomen, not through the spinal column
Brace used for scoliosis correction?
Milwaukee Brace
CTLSO - consists of neck ring supported by bars from the thoracolumbar region, which allows for forces to be generated to correct a scoliotic spine
Must be worn at all times (23hrs per day, except for bathing) until skeletal maturity is reached
At what Cobb angle is bracing started for scoliosis?
20-40 degrees
> 40 degrees - surgical correction considered (>35 degrees for neuromuscular scoliosis)
Which TSLO promotes upright spine posture?
Taylor Brace/Knight-Taylor Brace
Used similar to Jewett and CASH braces, has straps that wrap around the shoulders (like overalls)
Orthosis used in spasticity or burn patients with the goal of preventing contractures?
Resting hand splint
Positioning of a resting hand splint?
Intrinsic plus position
Slight wrist extension, MCP flexion 70-90 degrees, thumb in palmar ABDuction, PIPs and DIPs in extension (functional “C” shape position)
Indication for a tenodesis orthosis?
Often used in SCI pts w/ NLI of C6 (pt has some wrist extension power, but nothing in C7 roots or below - no hand or finger control)
Brace extends the wrist, approximating the fingers with the thumb, allowing for a more functional grasp by the patient
Name of orthosis?
Soft hollow tube that rests in pt’s hand, allowing them to pick up objects ad manipulate them (e.g. fork/spoon)
Universal cuff
Name of orthosis?
Immobilizes the thumb; can be a long version that prevents radial or ulnar deviation of the wrist as well
Opponens orthosis
Immobilizes thumb to allow healing (often for a ligamentous injury or OA of the CMC)
Flexion/extension pattern in swan neck deformities?
swan neck ring splint counteracts in which directions?
Swan neck:
MCP flexion, DIP extension, PIP flexion
Ring splint: MCP extension, DIP flexion, PIP extension
Flexion/extension pattern in Boutonniere deformities?
Boutonniere ring splint counteracts in which directions?
Boutonniere”
MCP extension, DIP flexion, PIP extension
Ring splint: MCP flexion, DIP extension, PIP flexion
Minimum strength required for use of a balanced forearm orthosis/shoulder-elbow-wrist-hand orthosis?
2/5 elbow flexor and 2/5 shoulder girdle strength
Supports the hand, wrist, elbow, and shoulder joint via a complete housing apparatus that allows pt to feed themself
When are AFOs w/ double metal uprights indicated?
when there is fluctuating limb volume, skin sensitivity, or skin breakdown
Role of pins in AFOs?
Pins prevent
Anterior = prevents dorsiflexion
Posterior = prevents plantarflexion
Role of springs in AFOs?
Springs promote
Anterior. = promote plantarflexion
Posterior = promote dorsiflexion
Pins in the anterior channel of an AFO will ______?
prevent dorsiflexion
Springs in the anterior channel of an AFO will ______?
assist/promote plantarflexion
Pins in the posterior channel of an AFO will _________?
prevent plantarflexion
Springs in the posterior channel of an AFO will ______?
assist/promote dorsiflexion
Which AFO is indicated for flaccid foot drop (patient has medial/lateral control of the ankle, and control of progression of the tibia)?
Posterior Leaf Spring
Patients w/ pure foot drop, but have medial/lateral control of the ankle and control progression of the tibia
Which AFO is indicated for pts w/ significant lower leg weakness but have some tibial control in the sagittal plane?
Hinged-solid AFO/Semirigid AFO (trim line just behind the malleoli)
Allows for some sagittal plane movement (which requires more strength to control)
Which AFO is indicated for pts w/ significant limb weakness, absent ankle control, spasticity when weight-bearing, knee buckling, and foot drop?
Solid AFO
Provides maximum stability while eliminating ankle ROM
Which is a more rigid thermoplastic for AFOs:
Polypropylene vs. copolymer
Polypropylene
Relatively rigid plastic that is durable, but more difficult to mold than other plastics
*Low-density polyethylene is less rigid, more flexible, and easier to mold
*Copolymer is a blend of polyropylene and polyethylene, provides intermiediate levels of structural rigidity
Which orthotic is indicated for patients that have impaired muscular control of the ankle and knee?
Knee-Ankle-Foot Orthosis (KAFO)
Often the hinge joint is offset posteriorly to patient’s knee, which causes the line of gravity to fall anterior to the knee, tending to lock it in extension (useful in patients with weak quadriceps whose knees would otherwise buckle)
Contraindication for bail lock use in KAFOs?
bilateral use
Bail locks automatically lock the KAFO in extension when the knee is extended; to unlock the knee, the patient pulls up on a lever near the knee
Type of KAFO indicated for a paraplegic patient with some preserved hip flexion?
Scott-Craig KAFO
Allows paraplegic pts to stand without assistance- relies on iliofemoral ligament (posteriorly offset knee joint to passively promote knee extension)
Knee orothosis indicated following an ACL tear to prevent further stress to the ligament?
Lennox-Hill Derotation Orthosis
Knee orthosis indicated to prevent genu recurvatum using a 3-point pressure principle?
Swedish Knee Cage
Knee orthosis that reduces forces in the foot and ankle?
Patellar Tendon-Bearing Orthosis
Uses uprights from the ankle to transmit forces into the patellar tendon so it can share the load of weight-bearing
What type of heel wedge should be used to offload the medial compartment of the knee for OA pain?
Lateral heel wedge
Pros/cons of small caster wheels on a WC?
smaller casters = easier to maneuver and turn WC, will get caught on every pebble
standard/optimal size = 8 inch
Pros/cons of placing rear WC wheels more anteriorly?
Pros: easier to maneuver chair, smaller turning radius, easier to do wheelies and go up curbs
Cons: less stable (easier to tip back going up inclines)
Pros/cons of placing rear WC wheels more posteriorly?
Pros: more stable
Cons: harder to maneuver, harder to accelerate, harder to ascend inclines
Pros/cons of increasing WC camber angle?
Pros: allows for really tight turns (i.e. better for WC sports)
Cons: increases width of chair, may not fit through standard doorframes
Ideal WC backrest height?
just below the bottom corner of the scapula
Pros/cons of recline feature in WC?
Pros: allows access for I/O cathing
Cons: increases shear forces on back/posterior
Ideal cane height?
level with greater trochanter, or level of the hand when elbow is flexed 20-30 degrees
Prosthetic knee indicated for single-speed walking (can include manually locking feature)?
Single-axis/constant friction knee
Very durable, also used for low-build heights
Prosthetic knee that locks the knee in extension during weight bearing?
Weight-activated stance control (WASC) knee
Good for initial prosthetic training to help with weight shifting, helpful for patients with poor hip control
Must be unloaded to unlock knee for sitting or flexion - causing delayed swing phase; can’t use on stairs
Most aesthetically pleasing prosthetic knee for sitting w/ equal leg lengths (low profile)?
Polycentric knee
Most commonly has 4 axis points (4 linkage bars), changing center of rotation = very stable during stance, but does not disturb swing phase
useful for long TF or knee disarticulation amputees due to. low profile
Prosthetic knees indicated for variable walking speed/cadence?
Fluid controlled knee - utilize oil or pneumatic cylinder with piston; hydraulic stance control also improves stability. Cons: heavier, more expensive, requires more maintenance, can be fabricated w/ microprocessor control
Microprocessor knee - allows for variation in both swing and stance phase on a moment-to-moment basis; stumble control features
prostetic feet indicated for K1 ambulators?
SACH (solid ankle, cushioned heel) foot
- Includes a foam heel and solid wooden keel. Inexpensive, durable, useful in less active amputees, but not energy-efficient. Also useful in Syme amputations
Single Axis Foot
- allows movement in sagittal plane w/ mechanical bumper on either end to modulate dorsiflexion/plantar flexion
- Rapid flat foot can improve knee stability, but can also cause abrupt knee hyperextension (not recommended for trans-tibial amputees)
Prosthetic feet indicated for K2 ambulators?
Multiaxial foot
- allows motion in the dorsi/plantar flexion lane, and inversion/eversion planes for uneven surfaces (can be costly and heavy)
Stationary ankle, flexible endoskeleton (SAFE) foot
- useful for uneven surfaces
Prosthetic foot indicated for K3/K3 ambulators?
Energy Storing Foot (aka Dynamic elastic response foot)
- Allows for more dynamic push-off and mechanical energy return; often made of carbon fiber; good for variable cadence
Possible causes for circumduction in the gait of a transfemoral amputee include?
Excessive mechanical resistance to knee flexion (knee friction too high)
Prosthesis too long
Increased medial brim pressures
inadequate suspension
patient lacks confidence or has inadequate hip flexion
