The increasing use of back-sleeping positions, which significantly reduces the risk of Sudden Infant Death Syndrome, has led to a rise in positional head flattening in infants. This condition, known clinically as deformational plagiocephaly or brachycephaly, occurs because the baby’s skull bones are soft and malleable in the early months of life. While many cases improve naturally or with simple changes, some infants develop moderate to severe flattening that warrants professional intervention. Cranial orthosis, or helmet therapy, is a time-sensitive treatment used to gently reshape the skull when non-invasive methods prove insufficient.
Identifying Different Head Shapes
Parents often notice a flat spot on their baby’s head, which usually falls into one of two primary categories of positional deformation. Positional plagiocephaly is characterized by an asymmetrical shape when viewed from above. Flattening occurs on one side of the back of the head, and this pressure often causes the ear, and sometimes the forehead, on the same side to shift forward.
Positional brachycephaly, in contrast, involves a symmetrical flattening that spans the entire back of the head. This flattening causes the head to appear wider than normal, resulting in a disproportionately high or tall shape toward the back. A combination of both plagiocephaly and brachycephaly is also common. These positional issues must be distinguished from craniosynostosis, a rare condition where the skull’s growth plates fuse prematurely. Craniosynostosis requires surgical intervention because it can impede brain growth, whereas positional flattening does not affect brain development.
Initial Steps and Repositioning Therapy
Before considering a helmet, the first line of intervention involves conservative, at-home measures focused on repositioning and strengthening the infant’s neck muscles. This strategy aims to relieve pressure on the flattened area of the skull by encouraging the baby to turn their head away from it. Supervised tummy time is a foundational practice that should begin early, starting with short sessions of three to five minutes, two or three times a day. The goal is to gradually increase this to a total of 20 to 30 minutes daily by the time the baby reaches about seven weeks of age.
Active repositioning during wake time involves deliberately encouraging the baby to look in the direction opposite the flat spot. Techniques include changing the direction the baby lies in the crib so they look out into the room, and alternating the arm used when holding or feeding the baby. Parents should also reduce the time spent in carriers or car seats, which apply constant pressure to the back of the head. If a baby consistently favors turning their head to one side, they may have torticollis, a tightening of the neck muscles. Physical therapy is often recommended to stretch the muscle and restore a full range of neck motion, which is necessary for effective repositioning.
Criteria for Helmet Recommendation
The decision to recommend a cranial orthosis is based on objective clinical metrics. Specialists use precise measurements, often obtained through a 3D surface scan or specialized calipers, to quantify the severity of the head shape deformation. For plagiocephaly, the primary metric is the Cranial Vault Asymmetry Index (CVAI), which measures the difference between diagonal skull diameters. A CVAI score greater than six or seven percent, or a Cranial Vault Asymmetry (CVA) exceeding 10 millimeters, indicates a moderate to severe case warranting helmet therapy if conservative measures have failed. For brachycephaly, the Cephalic Index (CI) is used, measuring the ratio of the head’s width to its length; a CI exceeding 90 percent is considered a threshold for significant brachycephaly.
The most crucial factor influencing the success of helmet therapy is the infant’s age at the start of treatment. The skull grows most rapidly between four and six months of age, making this the optimal window for the most effective and shortest treatment time. While treatment can still provide improvement in older infants, its effectiveness decreases significantly after six months. Treatment is generally considered ineffective past 12 to 18 months, as skull growth slows substantially.
The Helmet Treatment Process
Once clinical measurements confirm the need for intervention, the cranial orthosis is custom-fabricated to fit the baby’s head precisely. The helmet works by providing snug contact over the prominent areas of the skull while leaving a small space over the flat areas. This design redirects the natural, rapid growth of the baby’s head into the flat spots, encouraging a rounder shape. The helmet must be worn for approximately 23 hours per day, only being removed for bathing and brief skin checks. The average duration of the treatment typically ranges from two to six months, depending on the baby’s age, the severity of the condition, and the rate of head growth. Regular follow-up appointments are scheduled every few weeks to allow the orthotist to make precise internal adjustments as the baby’s head shape changes.