Prosthetic Review Questions:

An elderly patient with a transfemoral amputation is being fitted with a temporary prosthesis containing a SACH (solid ankle cushion heel) prosthetic foot. Which of the following BEST characterizes the SACH foot?

• Is an articulated foot with multiplanar motion.

• Allows full sagittal and frontal plane motion.

• Absorbs energy through a series of bumpers, permitting sagittal plane motion only.

• Allows limited sagittal plane motion with a small amount of mediolateral motion.

Answer explanation

The SACH foot provides sagittal plane motion (primarily plantarflexion) but the heel cushion is compressed and there is very limited frontal plane motion (mediolateral).

Articulated feet have rubber bumpers that absorb shock and control plantarflexion excursion.

A therapist is examining the gait of a patient with a transfemoral prosthesis. The patient circumducts the prosthetic limb during swing. The therapist needs to identify the cause of the gait deviation. What is the MOST likely prosthetic cause?

• Unstable knee unit.

• Inadequate socket flexion.

• High medial wall or abducted hip joint.

• Increased knee flexion resistance.

When using a transtibial total surface bearing prosthesis, a patient experiences excessive knee flexion in early stance. What is the MOST likely cause of this problem?

• Socket is aligned too far back or tilted posteriorly.

• Foot position is inset too much.

• Socket is aligned too far forward or tilted anteriorly.

• Foot position is outset too much.

A patient with a transfemoral amputation and an above knee prosthesis demonstrates forward trunk leaning during the stance phase of gait with a rolling walker. What is the MOST LIKELY cause of this gait deviation?

• Prosthesis is too long.

• Walker is set too high.

• Weak gluteus maximus.

• Unstable knee unit.

After gait training a patient with a transtibial prosthesis, a therapist notices redness along the patellar tendon and medial tibial flare. What would this finding indicate?

• The socket is too small and the residual limb is not seated properly.

• The socket is too large and pistoning is occurring.

• There is improper weight distribution during stance.

• Pressure-tolerant weight bearing is occurring.