During single-leg support, the hip abductors prevent which of the following?

During single-leg support, the hip abductors prevent which of the following?

• A. Contralateral pelvic drop
• B. Ipsilateral shoulder drop
• C. Excessive toe extension
• D. Passive knee flexion

Answer: (A)

During single-leg support, gravity pulls the pelvis toward the unsupported side. The stance leg’s hip abductors (gluteus medius and minimus) create a frontal-plane moment that keeps the pelvis level, preventing the pelvis from dropping on the opposite side. This stabilizing action maintains a level pelvis as you stand on one leg; when these muscles are weak, the pelvis tends to sag on the contralateral side (a Trendelenburg-type effect). Other options don’t reflect this primary stabilizing role: shoulder position isn’t governed by the hip abductors, toe extension concerns the foot/ankle, and knee motion isn’t directly controlled by these hip muscles during single-leg stance.

During single-leg support, gravity pulls the pelvis toward the unsupported side. The stance leg’s hip abductors (gluteus medius and minimus) create a frontal-plane moment that keeps the pelvis level, preventing the pelvis from dropping on the opposite side. This stabilizing action maintains a level pelvis as you stand on one leg; when these muscles are weak, the pelvis tends to sag on the contralateral side (a Trendelenburg-type effect).

Other options don’t reflect this primary stabilizing role: shoulder position isn’t governed by the hip abductors, toe extension concerns the foot/ankle, and knee motion isn’t directly controlled by these hip muscles during single-leg stance.