Effectiveness of Tortle Midliner Positioning System on the Prevention and Treatment of Cranial Molding Deformities in Preterm Infants

Dolichocephaly (or positional scaphocephaly) is defined as a boat-shaped or elongated
anterior-posterior axis as a result of skull flattening during side-to-side head positioning
of infants during hospitalization. This deformity often takes place in preterm infants <32
weeks because the preferred position is sidelying or prone for improved ease of containment,
decreased reflux episodes, and decreased apnea/bradycardia. Supine positioning with head in
midline is recommended to decrease the occurrence of this deformity, but maintaining midline
is difficult as a result of gravity and preterm hypotonia. Developmental positioning through
use of special positioning aids and caregiver education are common interventions used to
address dolichocephaly. Dolichocephaly may resolve prior to hospital discharge, but in some
cases infants are discharged home with the deformity.

Despite documentation of dolichocephaly in preterm infants for nearly three decades, few
studies report how often it occurs or the rate of resolution with intervention. Prematurity
appears to be the most common predetermining factor. Preterm infants may experience a
limited variety of positions due to autonomic instability or critical respiratory status.
These infants are often positioned in prone to improve oxygenation and decrease incidence of
reflux. Furthermore, the preterm infant demonstrates proximal hypotonia, causing the head to
fall to either side with gravity while in supine. Bilateral flattening of the lateral skull
develops as a result of the weight of the head and the pressure of gravity.

The correlation between low birth weight and head flattening has been established in the
literature. Researchers suggested that the deformity was preventable with the use of air or
water pillows. Limited emphasis was placed on body position (i.e. supine, sidelying, or
prone) in these articles. Since this period of time, the use of positioning aids and
developmental positioning has been used to decrease the occurrence of dolichocephaly during
hospitalization. Despite these interventions, some infants have dolichocephaly at hospital
discharge.

The long-term consequences of dolichocephaly are not fully known, but it has been correlated
with delayed reaching skills, tightness in the spinal extensors and scapular retractors, and
development of motor asymmetries. Other long-term effects of dolichocephaly have been
evaluated minimally. Elliman's study demonstrated comparable developmental quotients at age
3 when comparing a preterm group to controls. Kitchen and colleagues reported no differences
in IQ at a 7-year follow up. Mewes and colleagues, however, suggest that the shift in
cortical structures, caused by dolichocephaly may affect the preterm brain, which continues
to develop rapidly after birth. Since the American Academy of Pediatrics established the
widely successful and influential "Back to Sleep Campaign" in 1992, many studies have
established the relationship between prevalence and long-term neuro-developmental outcomes
of preterm infants with plagiocephaly - asymmetric flattening of the skull due to head
preference - but there are no studies that determine the long-term neuro-developmental
outcomes of preterm infants with dolichocephaly. Increased time spent supine, coupled with
the fact that nearly half of preterm infants leave the hospital with a head preference,
calls for updated long-term study of the effect of dolichocephaly specifically on
neuro-developmental outcomes.

Inclusion Criteria:

1. Birth weight of <1500 g

2. Gestational age of ≤ 30 weeks

3. <2 weeks chronological age

4. ≤30 weeks gestation at time of parent consent

5. Receiving continuous positive airway pressure (CPAP), nasal cannula or room air

6. Signed the informed consent from the legal caregiver

Exclusion Criteria:

1. Determined to be too medically unstable by their attending physician

2. Diagnosed with a genetic/chromosomal abnormality, congenital neuromuscular disorder,
craniofacial abnormalities, congenital hydrocephalus, post-hemorrhagic hydrocephalus,
or other diagnoses determined by the PI that impacts generalizability of results