Which condition involves a rupture of blood vessels beneath the periosteum, causing localized swelling?

The condition characterized by a rupture of blood vessels beneath the periosteum, leading to localized swelling, is cephalohematoma. This typically occurs during delivery, particularly with the use of instruments like forceps or vacuum extraction. When blood vessels rupture, blood accumulates between the periosteum (the membrane covering the skull) and the skull bone itself, resulting in a firm, raised area that is usually confined to one cranial bone and does not cross suture lines.

In contrast, caput succedaneum refers to edema of the soft tissues of the head due to pressure during delivery. This swelling is often diffuse and crosses suture lines, distinguishing it from cephalohematoma. Sub-galeal hematoma involves bleeding between the galea aponeurotica (a layer of connective tissue) and the periosteum, which can also result in significant swelling but does not localize solely beneath the periosteum as seen in cephalohematoma. Breech presentation is a fetal positioning issue with no direct relation to blood vessel rupture or subsequent swelling. Therefore, cephalohematoma is the most accurate answer to the question posed.