Positional Plagiocephaly
When an infant is born the skull can be abnormally shaped due to craniosynostosis or positional deformities. Craniosynostosis involves the premature fusion of the bones of the skull that can restrict growth. This condition called craniosynostosis needs to be surgically treated. However, the most common condition by a great margin is abnormal skull shapes that result from outside pressure slowly molding the skull shape over time. The most common of these is flattening of one side of the back of the head. This is also frequently associated with a condition called toricollis- tight muscles on one side of the neck. The neck muscle can be slightly shortened on one side causing the child to sleep predominantly on one side of the head. Over time, the back of the head becomes progressively flatter from the constant pressure. This usually becomes noticeable around two months of age and continues to progress over the next four months. Once the child starts to roll over ( 5-6 months of age ) the flatness stops progressing and slowly starts to improve.
The diagnosis of positional plagiocephally is usually made on a physical exam. Flattening on one side frequently causes the forehead on that side to be more prominent – giving the head a parallelogram shape. Very rarely a fused lambdoidal suture can cause flattening of the back of the skull. If suspected, then a CT scan needs to be performed to confirm or rule out fusion of the lambdoid suture. In lambdoid synostosis, the height of the skull on the fused side is usually decreased. Most craniofacial surgeons agree that positional plagiocephaly does not cause any problems with the brain of the child’s development.
Treatment consists of three options.
1) Observations
2) Positioning off the affected side
3) Helmet therapy. In my experience, skull flatness will improve over time with no aggressive treatment. Because of this, I think helmet therapy is rarely indicated.