A patient with weak hip abduction may compensate by which movement during midstance?

A patient with weak hip abduction may compensate by which movement during midstance?

• A. Lateral bending toward the weak side
• B. Lateral bending away from the weak side
• C. Forward trunk flexion
• D. Backward trunk lean

Answer: (A)

During midstance, the hip abductors of the stance leg keep the pelvis level in the frontal plane by counteracting the body’s weight. If those abductors are weak, the pelvis tends to drop on the opposite side. To compensate, the person leans the trunk toward the stance leg (toward the weak side). This lateral trunk flexion moves the center of mass over the stance hip, reducing the external moment the weak abductors must resist and helping maintain pelvis level during single-leg support. Moving the trunk away from the weak side would not help stabilize the pelvis, and forward or backward trunk movements aren’t the primary midstance strategies for this weakness.

During midstance, the hip abductors of the stance leg keep the pelvis level in the frontal plane by counteracting the body’s weight. If those abductors are weak, the pelvis tends to drop on the opposite side. To compensate, the person leans the trunk toward the stance leg (toward the weak side). This lateral trunk flexion moves the center of mass over the stance hip, reducing the external moment the weak abductors must resist and helping maintain pelvis level during single-leg support. Moving the trunk away from the weak side would not help stabilize the pelvis, and forward or backward trunk movements aren’t the primary midstance strategies for this weakness.