For a patient with bilateral transfemoral amputations attempting to maximize balance in a wheelchair, the rear wheels should be positioned more:

For a patient with bilateral transfemoral amputations attempting to maximize balance in a wheelchair, the rear wheels should be positioned more:

• A. laterally
• B. posteriorly
• C. anteriorly
• D. inferiorly

Answer: (B)

Wheelchair balance hinges on center of gravity relative to the base of support. When the rear wheels are placed more toward the back (posteriorly), the rear axle moves farther behind the user’s center of gravity. This increases the tipping threshold for backward tipping and enlarges the backward portion of the base of support, making it easier to maintain balance—especially for someone with bilateral transfemoral amputations who lacks distal support from feet. If the wheels were moved toward the front, tipping forward would become more likely when the user leans forward. Lateral shifts mainly affect side-to-side stability, and changing height (inferiorly) changes seat height rather than backward tipping risk. Therefore, positioning the rear wheels posteriorly best enhances overall balance for this patient.

Wheelchair balance hinges on center of gravity relative to the base of support. When the rear wheels are placed more toward the back (posteriorly), the rear axle moves farther behind the user’s center of gravity. This increases the tipping threshold for backward tipping and enlarges the backward portion of the base of support, making it easier to maintain balance—especially for someone with bilateral transfemoral amputations who lacks distal support from feet.

If the wheels were moved toward the front, tipping forward would become more likely when the user leans forward. Lateral shifts mainly affect side-to-side stability, and changing height (inferiorly) changes seat height rather than backward tipping risk. Therefore, positioning the rear wheels posteriorly best enhances overall balance for this patient.