 Shoulder dystocia is a rare but dangerous scenario where the babys head is delivered, but the shoulders are trapped behind the pubic bones. The McRoberts position is used in this situation to deliver the baby. The mothers legs are flexed, and pushed up and out, lateral to her abdomen. It is believed that this helps by flattening out the sacral bone tail bone, thereby widening the bony opening and allowing the shoulders to become free. 