Ballert Orthopedic :: Newsletters and Articles

Caveat Emptor: Not All Helmets Are Alike
By Gene Bernardoni, CO - December 2002

In the world of cranial molding helmets, design plays an important role in determining patient outcomes. A good design can also reduce or eliminate the need to use multiple helmets throughout the course of treatment.

Over the many years that Ballert has been manufacturing and fitting cranial molding helmets (for the treatment of positional plagiocephaly), our helmet design has evolved as a tactical solution to treatment challenges.

Our observations post helmet/band therapy show that design-related problems can occur in several areas, from unwanted bulging over the ears, to turricephaly and/or ridges, and even to cranial elongation (scaphocephaly).

The Top Opening
The opening at the top of the helmet permits heat dissipation. In some models, the hole is so large that a condition known as turricephaly (an exaggerated heightening of the skull) can develop. (See Figures. 1 and 2a below.)

Figure 1	Figure 2
A large top opening in the helmet can permit the development of turricephaly, an exaggerated heightening of the skull.	Problems are sometimes caused by (a) a too-large opening at the top, (b) excessive space around the ears, (c) the seam at the back and (d) the closing gap on the side.

The smaller top hole of the Ballert helmet helps to reduce the risk that the skull can heighten through it (Fig. 3a). And heightening that predates the helmet can be controlled by shifting the top hole off center to cover the heightened area, thereby preventing further deformation. Heat dissipation is permitted not only through the smaller top hole, but also through the vent holes, which are discussed below.

Trimlines
Some designs are trimmed to permit large open spaces above and around the ears. We have found that in certain cases, these ear openings can permit unwanted medial-lateral growth from the late closing sutures (e.g., sqamosal, occipitomastoid and sphenotemporal).

In contrast, the Ballert helmet is designed to fit close around the ears, a feature that prevents the development of the bulging described above. (Compare Figures. 2 and 3.)

The Closing Mechanism
Many helmets and bands are constructed by thermoforming the plastic with the helmet mold on its side, leaving an irregular seam which when trimmed away reates a variable sized opening (Figure 2d).

Some helmet makers use accordian pleats, rubber bands, springs or the like to close or fill the opening, but there is not a uniform seam, and it is not possible to control its width. These mechanisms leave mothers with the dilemma of not knowing exactly how much to tighten the helmets. In addition, the large gap at the side of the head may also contribute to a bulging from late-closing sutures (see Figures. 2b and 2d.)

The Ballert helmet is constructed from a single piece of plastic draped over a cast of the skull. After the plaster cools, the single seam along the side is cut in an interlocking way, eliminating completely the gap of closure seen on many other helmet designs. (See Fig. 3.) The interlocking design acts as a solid, unseamed helmet by preventing sheer and thereby fostering a more symmetrical correction.

Figure 3. Advantages of the Ballert Helmet: (a) A smaller hole at the top; (b) seamless construction; (c) an interlocking closing with no gap; (d) close trimming around the ears; (e) vent holes for heat dissipation; and (f) multiple, removable layers of foam lining.

Lining
The Ballert helmet has multiple removable layers of foam lining, all of which are unseamed (unlike others: see Fig. 2c). This allows the practitioner to modify the helmet as the infant’s cranium grows, thereby reducing or eliminating the need for multiple helmets. (See. Fig. 3f.) In those helmets in which the liner is seamed, the ridge of the seam can be irritating to the infant’s scalp.

Vent Holes
Finally, the placement of vent holes only over the void areas helps to prevent the development of window edema (dimpling of the scalp) on the areas where pressure develops. (See Fig. 3.) The vent holes also allow the orthotist to verify that the helmet does not contact skull in these void areas.

Conclusion
Because the window of opportunity for correcting positional plagiocephaly is small, Ballert feels that the Ballert helmet is a wise choice for three primary reasons: First, our helmet provides more complete coverage of the skull, directing growth only to the flat spots of the skull, and facilitating quicker correction of the condition. Second, the Ballert helmet helps to prevent unwanted growth superior to the ears and at the top of the head. Third, a bonus may be a quicker correction due to limiting skull growth to only the void areas.