In shoulder dystocia, which manoeuvre directly enlarges the true conjugate of the pelvis by flattening the lumbar lordosis?

• A McRoberts manoeuvre ✓
• B Rubin II manoeuvre
• C Woods screw manoeuvre
• D Zavanelli manoeuvre

Explanation

McRoberts manoeuvre (hyperflexion of maternal thighs onto the abdomen) flattens the lumbar lordosis, rotating the symphysis pubis superiorly and increasing the relative anteroposterior diameter available for shoulder passage; it also straightens the sacrum relative to the lumbar spine. Rubin II and Woods screw are rotational manoeuvres that adduct or abduct the shoulders to reduce the bisacromial diameter. Zavanelli involves cephalic replacement and is a last-resort manoeuvre.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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