Hip abductors are especially active during single limb support to prevent what?

Hip abductors are especially active during single limb support to prevent what?

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

Answer: (B)

During single-limb support, the hip abductors on the stance leg produce a lateral force that keeps the pelvis level in the frontal plane. This counteracts the tendency for the pelvis to drop on the opposite side due to the body's weight shifting to that leg. If these muscles are weak, the pelvis trends downward on the unsupported side, producing a contralateral pelvic drop (a hallmark of a Trendelenburg pattern). The other options don’t address how the pelvis is stabilized during one‑leg stance: shoulder drop relates to trunk control, excessive toe extension is about foot mechanics, and passive knee flexion concerns knee posture rather than pelvic alignment.

During single-limb support, the hip abductors on the stance leg produce a lateral force that keeps the pelvis level in the frontal plane. This counteracts the tendency for the pelvis to drop on the opposite side due to the body's weight shifting to that leg. If these muscles are weak, the pelvis trends downward on the unsupported side, producing a contralateral pelvic drop (a hallmark of a Trendelenburg pattern). The other options don’t address how the pelvis is stabilized during one‑leg stance: shoulder drop relates to trunk control, excessive toe extension is about foot mechanics, and passive knee flexion concerns knee posture rather than pelvic alignment.