Card Set Information
What are the 2 types of transfemoral sockets?
What is the shape of the quadrilateral socket?
What is the shape of the CAT-CAM?
How is the ishium supported with a quadrilateral socket?
rests on socket on posterior shelf (ishcial seat)
How is the ishium supported with a CAT-CAM?
ischial tuberosity and part of the ischiopubic ramus are contained inside the walls
With what socket type is the inguinal pressure increased with sit->stand?
What type of gait deviations are seen with a quadrilateral socket?
What is the fit/alignment of the transfemoral socket like?
should be total contact with good contact on every area of the limb
distributes load over max area
provides counter pressure to assist venous return and prevent distal edema
enhances sensory feedback to foster better control
designed to emphasize loading on pressure tolerant structures (ishial tuberosity, gluteal musculature, sides of thigh, somewhat the distal end of the limb)
must avoid excessive pressure on pubic symphysis and perineum
Why do transfemoral sockets have a slight flexion aspect?
reduce lumbar lordosis
allows for approx equal step length
What is stance phase knee ext and stability created by aligning the knee joint posterior to the vertical knee axis line?
What are components?
parts of the prosthesis
What is dynamic alignment?
slight mvmt of the foot or knee component in relationship to the socket to provide the client with an optimum gait
can only be done after the client has learned to walk with the prosthesis
What is a lightweight metal tube to connect the components?
soft foam cover that matches the color and configuration of the other leg covers the shank
What is a wood or rigid polyurethane covered with a rigid plastic lamination?
What is pistoning?
dropping of prosthesis away from the residual limb during swing phase of gait
usually occurs with inadequate suspension
What is the part of the prosthesis corresponding to the lower leg of the unamputated limb, or the part that connects the foot to the socket/knee unit?
includes the pylon and cosmetic cover of the endoskeletal and is the finished part of the exoskeletal
What is the component into which the residual limb is inserted?
What is static alignment?
placing the prosthetic components in proper relationship to each other in the standing position
the socket, knee component, and foot are placed to duplicate the trochanter, knee, and ankle relationships of the nonamputated leg
What is the stance phase stability of the transfemoral prosthesis that is controlled by the clients extension of the residual limb against the posterior wall of the socket?
voluntary knee control
What are 4 possible features of knees?
What are the advantages of a single axis knee?
What do polycentric knee axis's provide?
efficient glide-slide motion
varying stability through stance by placing the line of force for knee rotation posterior to wearers weight line
shortens shank during swing phase for better toe clearance
allows shank to rotate under knee when sitting
complex, less durable
What modifies the pendular action of the knee?
constant friction device
variable friction device
What is a constant friction device?
friction remains constant at all phases of gait
pt can alter the amt of friction by tightening or loosening the clamp
clamp grabs the knee bolt
*only constant swing phase control
*no stance control
What is a variable friction device?
friction changes during swing phase to accommodate to varying gait speeds
better knee for more active ppl
when wearer walks faster, knee friction increases instantly
increases symmetry in the limbs
can be affected by temperature
hydraulic swing control:high cost, heavy
hydraulic swing and stance control
: has braking mechanism for stance phase control, high cost, heavy, may need more maintenance
What is a pneumatic knee?
more responsive to changes in gait speed than constant friction
may need more maintenance
less friction than hydraulic
What is a microprocessor knee?
C leg (name brand)
programmed to achieve optimal gait (speed and quality)
can analyze pts gait and adjust accordingly
What is an extension aid (kick strap)?
elastic webbing placed along the front of the knee axis, elastic stretches when the knee flexes in early swing and recoils to extend the knee in late swing
What are the advantages/disadvantages of an extension aid?
: simplest method, external aid, easily ajusted
: knee tends to extend in sitting
What type of extension aid allows the knee to remain flexed in sitting?
internal elastic strap or coiled spring
What are some characteristics of a manual lock knee?
security all pahses of gait and total stability in stance
knee wont flex when locked
shank will be shortened to accommodate for lack of flexion
can lead to hip hiking and circumduction gait
no swing phase
good for those with significant knee instability/weakness
What are the characteristics of a weight activted stance control (stance control knee)?
knee is locked during stance only, when weight is through the prosthesis
bock safety knee
good for single speed ambulators
during stance if knee is flexed <10-15 degrees, knee is locked
: bilateral amputees
possible hip hiking, circumduction
What are the characteristics of a SACH foot?
solid ankle cushion heel
posterior portion has a cushion with variable densities (softer for lighter pt, harder for bigger pt)
no propulsion at terminal stance
What type of foot prosthesis is more flexible than a SACH?
solid ankle flexible endoskeleton
posterior heel cushion
What motions do single axis articulated ankles allow for?
has 2 rubber bumpers:
post bumper controls amt of PF; ant bumper controls amt of DF
What motions do a multi axis articulated ankle allow for?
DF/PF - has ant/post bumpers
INV/EVER - has medial/lateral bumpers
medial controls amt of INV
lateral controls amt of EVER
What is dynamic response?
energy is stored in a flexible shank and keel and is released at toe off
use plastic or carbon fiber foot-ankle-shank
propulsion at terminal stance