Special Pops - Transfemoral Prosthetics (slide 53 until end)

The majority of prosthetic knees give what kind of benefit to gait?

• stance phase stability

• swing phase mobility

What are some benefits of a single axis knee?

• very durable and light weight

• heavy and stiff

• has constant friction during stance and swing phase

• amputees must use their own muscle power to keep them stable when standing

What are some benefits of the stance-control knee / "safety knee?"

• weight activated (knee won't bend until the weight is displaced)

• very safe and often used as a first time prosthesis for the knee

• does not have constant friction

• does have constant friction

• has a braking mechanism to keep the person's knee from buckling

What are some benefits of the polycentric knee / "four bar knee?'

• provides good stability for early stance phase

• overall leg length shortens when a step is initiated, reducing the risk of stumbling

• usually has expensive parts that need to be serviced/replaced

• good versatility for various levels of amputees

What are some benefits of the hydraulic knee?

• cadence responsive (closest to operating like a real knee)

• requires more maintenance than other knees and usually more expensive

• improves gait symmetry and gait speed

• reduces stride time and improve swing phase symmetry

What are some of the benefits of the microprocessor knee?

• reduced energy requirements when walking

• increased speed on uneven terrain

• improved gait pattern during stair navigation

• decreased wear and tear on the unaffected limb

Your pt w/ a prosthetic knee has mastered walking on uneven terrain and you would like to progress her to walking up and down hills. How would you recommend she orient her body when walking up and down hills?

• when going downhill, lean backward to decrease momentum so you don't fall

• when going downhill, lean backward to align w/ the GRF at initial contact and loading response to "ride the friction" down

• when going uphill, lean forward to increase activation of your hip flexors

• when going uphill, lean forward to increase activation of your hip extensors

Your pt w/ a short residual limb and weak hip extensors is in need of a stable foot for their knee prosthetic. You want to recommend the foot to be able to do what when sending a referral to the prosthetist?

• a foot to reach terminal stance quickly to encourage forward momentum

• a foot that can reach foot flat quickly to enhance stance phase stability

• a foot than can reach foot flat quickly to enhance knee extension

• a foot to reach initial contact quickly to prevent knee buckling

What kind of foot what you recommend for a transfemoral amputee wanting to get back to walking on the greenway and trail walking?

• a stable foot that encourages stability

• a dynamic foot that promotes push-off

• a dynamic foot that is less likely to succumb to inversion/eversion

• a stable foot that reduces knee buckling