Positional Head Deformities
Positional head deformities, sometimes called deformational plagiocephaly, have dramatically increased in frequency (an incidence as high as 48%) following the 1992 recommendation by the American Academy of Pediatrics that all infants sleep on their backs to prevent sudden infant death syndrome (SIDS). Prolonged and preferential positioning of the head can lead to a characteristic change in skull shape. The back of the head is usually flat on one side, and the ear and forehead on the same side are rotated forward. Generally, these deformities are easily differentiated from craniosynostosis by a thorough examination. A CT scan is necessary in some cases to differentiate this disorder from others requiring surgery, but most often in experienced hands these diagnoses can be determined based on clinical exam.
Characteristic findings in positional head deformity include:
- Flatness of the back of the head on the affected side
- Flatness of the forehead on the opposite side
- Rotation of the ear forward on the affected side
- Fullness of the forehead on the affected side
- A trapezoidal shape of the skull
When diagnosed in the first year of life, children can usually be treated non-surgically using band or helmet therapy. Ideally, therapy is started at 6 months of age, when children begin to roll over and spend less time asleep. The skull is quite malleable during this first year, but begins to thicken and therefore becomes more difficult to shape after 12-14 months. Helmet, or banding therapy, involves making a mold of the skull, from which a model of the skull is then fashioned. This model is then rounded out and used to fabricate a form-fitting band or helmet that sits snugly against the prominent areas of the head. The flattened, recessed areas of the skull are permitted to gradually expand into the open areas of the band or helmet. Correction in skull shape usually occurs within three to six months. The helmet or band is made by a skilled orthotist working with a pediatric craniofacial surgeon, pediatric neurosurgeon, or pediatrician.
In older children, craniofacial surgery is necessary only when deformities around the forehead and eyes are severe and become a social stigma. This surgery is similar to that performed for craniosynostosis.
Head shape deformities may also be caused as a result of torticollis. Torticollis is most often an in-utero event involving the shortening and underdevelopment of the neck musculature on one side. Often, the baby will be positioned against the uterine wall and use the wall as crutch for head support and this may result in the neck lacking the musculature for strength and support. This musculature will usually develop outside of the womb in time. However, the resultant weakness on one side of the neck often causes a head tilt and a compensatory falling to the opposite side during sleep. This then secondarily causes ahead deformities. In this case, the torticollis must also be addressed to prevent relapse after molding therapy and lengthen and strengthen the neck muscles. Often, this is achieved with the help of physical or occupational therapist for daily exercises. In more severe cases, sometimes Botulism Toxin A (Botox) injections are employed. This paralyzes the injected muscles for approximately three months, allowing parents and therapist to better stretch the foreshortened and tight neck. Only in the most severe and refractory cases (less than 2%) require release of the tight neck muscles via a surgery.
With the use of the helmets, we expect a 90-95% correction in head shape. All human beings have some asymmetry in their skull and it is unrealistic and unnatural to expect perfect, rounded symmetry following any treatment of head shape. The typical length of a cranial remodeling treatment is directly dependent on the age at which the child begins this therapy. Molding therapy is not usually started until 6 months of age when many infants are likely to be able to roll over, thus changing the sleeping position more easily and often.