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Positional plagiocephaly: evaluation and management
Oral Maxillofacial Surg Clin N Am 16 (2004) 439 – 446
Positional plagiocephaly: evaluation and management John Caccamese, DMD, MDa, Bernard J. Costello, DMD, MDb, Ramon L. Ruiz, DMD, MDc,*, Ann M. Ritter, MDd a
Department of Oral and Maxillofacial Surgery, University of Maryland Medical System, 419 West Redwood Street, Suite 410, Baltimore, MD 21043, USA b Department of Oral and Maxillofacial Surgery, University of Pittsburgh Medical Center, Magee-Women’s Hospital, Children’s Hospital of Pittsburgh, 3471 Fifth Avenue, Suite 1112, Pittsburgh, PA 15213, USA c Oral and Maxillofacial Surgery/Pediatric Craniofacial Surgery, Southwest Florida Oral and Facial Surgery, 5285 Summerlin Road, Suite 101, Fort Meyers, FL 33919, USA d Department of Pediatric Neurosurgery, Children’s Hospital of North Carolina, University of North Carolina at Chapel Hill, 148 Burnett-Womack Building, Chapel Hill, NC 27599, USA
Plagiocephaly is a clinically descriptive term for an oblique or asymmetric head shape that does not imply a definitive diagnosis. Throughout the scientific literature, however, plagiocephaly frequently has been used broadly to describe asymmetries of the anterior or posterior cranial vault, often without differentiating between synostotic (ie, fused sutures) and nonsynostotic (ie, patent suture) deformities [1]. Understanding the heterogenous nature of plagiocephaly is critical because treatments vary dramatically depending on the specific underlying diagnosis. Depending on the specific cause of the cranial vault deformity, the required management may range from observation to more extensive intervention, including major surgery for reconstruction of the cranial vault. Congenital anomalies may be classified into several basic categories: (1) malformations, which result during embryogenesis (eg, craniosynostosis) and are morphologic defects of an organ, part of an organ, or a larger area of the body that result from an intrinsically abnormal developmental process, (2) deformations, which occur later in fetal life or postnatally and are alterations in the form or position of a previously normally formed structure secondary to nondisruptive me-
* Corresponding author. E-mail address: [email protected] (R.L. Ruiz).
chanical forces (eg, positional plagiocephaly), and (3) disruptions, which are morphologic defects of an organ or part of an organ that result from the breakdown or interference with an originally normal structure (eg, amniotic band disruptions) [2]. During the first 2 years of life, brain growth occurs at a rapid rate. In the newborn, the presence of open cranial vault sutures (eg, metopic, coronal, sagittal, and lambdoid) creates a flexible complex of cranial bones that allows the brain to expand. This flexibility of the cranium, which allows unrestricted brain development, also may permit the cranial vault to be deformed. ‘‘Positional plagiocephaly’’ is defined as a cranial vault asymmetry in the presence of patent cranial vault sutures. This type of skull molding or deformational plagiocephaly is commonly seen in neonates and infants, and previous intrauterine constraint, the birthing process, or repetitive sleep positioning all can contribute to the severity of the cranial vault asymmetry. In contrast, craniosynostosis is a malformation that occurs almost universally during fetal development and is defined as the premature fusion of a cranial vault suture or sutures that results in arrested skeletal growth and a head shape abnormality. The different forms of craniosynostosis each produce unique craniofacial dysmorphologies. Clinicians must be able to differentiate between the dysmorphic craniofacial patterns produced by
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J. Caccamese et al / Oral Maxillofacial Surg Clin N Am 16 (2004) 439 – 446
these different causes. This article presents the current diagnostic approach, differential diagnosis, and treatment options for positional plagiocephaly.
Incidence and etiology of positional plagiocephaly During the first few days of life, cranial molding that resulted from the passage of the child’s head through the birth canal or early decent into the mother’s pelvis is frequently noted. This asymmetry usually resolves spontaneously within the first several weeks of life in most infants. No treatment is required other than routine observation during wellbaby check-ups. Another group of children demonstrates normocephalic morphology after birth but subsequently develops cranial vault asymmetry during early postnatal development. This positional plagiocephaly is the result of postnatal external forces, usually from repetitive sleep positioning, that act on a flexible cranium. Previous reports have estimated the incidence of positional plagiocephaly as low as 1:300 and as high as 1:2 infants under the age of 1 year [3,4]. In contrast, the incidence of lambdoid suture craniosynostosis, which also produces posterior plagiocephaly, is approximately 1:150,000 live births [2]. Unilateral coronal craniosynostosis is another relevant condition because it produces anterior cranial vault asymmetry that may be confused with deformational changes. It has a relative incidence of approximately 1:10,000 live births [5]. In 1992, the American Academy of Pediatrics started the ‘‘Back to Sleep’’ campaign, which recommended that infants be placed on their sides or backs during sleep to reduce the risk of sudden infant death syndrome (SIDS) [6]. Since instituting the campaign in 1992, the incidence of SIDS has decreased by 40%. At the same time, however, a significant increase in the number of children referred for management of posterior plagiocephaly without synostosis was observed [7]. Early on, several centers reported a sudden increase in the number of unilateral lambdoid ‘‘synostosis’’ cases being seen. Later, it was realized that the increased number of referrals was actually repetitive sleep positioning that caused nonsynostotic posterior plagiocephaly [1,7]. Positional preference also has been recognized as a significant contributor to cranial asymmetry since the early 1990s. Positional preference merely refers to an infant or child’s preference in maintaining the head turned to one side most of the time. Active movements of the head to the opposite side are few, and passive mobility may be limited. Positional prefer-
ence may be associated with torticollis, ocular conditions, scoliosis of infancy, limited abduction of the contralateral hip, and foot abnormalities [8]. In a recent study performed in the Netherlands that involved a large cohort of patients, the prevalence of positional preference was noted to be 8.2% and was seen most commonly in children younger than 16 weeks of age. First-born children, premature children, and breech positioned infants were at the highest risk for positional preference. Supine sleeping positioning and repetitive positioning during feeding were positively correlated with positional preference [8]. Another potential contributing factor to positional plagiocephaly is congenital muscular torticollis (CMT). CMT is an abnormal head tilt that results from congenital tethering of one of the sternocleidomastoid muscles. The result of this unilateral muscular problem is a persistent aberrant head position that causes skull molding and asymmetry, which affect the anterior or posterior cranial vault. One theory regarding the cause of CMT has proposed that late intrauterine constraint leads to venous occlusion and damage of the sternocleidomastoid muscle [9,10]. This insult generally results in unilateral fibrosis and shortening of the sternocleidomastoid muscle. Other suggested causes include intrinsic malformations or ‘‘pseudo-tumors’’ of the sternocleidomastoid musculature, neurologic disorders, and hemiatrophy/hypertrophy [9,10]. Whatever the cause, the fetal head is molded while obliquely compressed by the muscle tethering. Consequently, contralateral deviation of the chin, lateral neck flexion, and decreased range of motion are frequently noted on examination. In infants in whom CMT is severe, the cranial asymmetry becomes more pronounced in the first few months of life as the infant’s head is maintained in a relatively fixed position. On physical examination, head tilt, limited neck range of motion, and contralateral facial flattening should be noted. Persing et al [4] recommend the rotating chair test to aid in making the diagnosis of CMT associated with positional plagiocephaly. To perform this test, the examiner holds the infant while the parent keeps the infant’s interest. The examiner rotates in the chair and observes the infant’s range of neck motion. The difference in neck mobility toward and away from the affected side may aid in making the diagnosis of CMT [1]. Slate et al [11] noted asymptomatic cervical spine subluxations in half of their study population with CMT. This finding coincided with a 62% rate of difficult or breech deliveries. Whether these findings were the result of birth trauma or unfavorable intrauterine positioning was not clear.
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Other researchers have suggested a less severe variant of CMT called sternocleidomastoid imbalance, in which the position of the neck is not fixed but only intermittently tilted with a normal range of motion attributable to a weakened sternocleidomastoid. This condition may be more common than CMT and more amenable to physical therapy [12]. If left untreated, however, the resultant head deformity remains the same. When positional plagiocephaly is associated with CMT, it is imperative that it be recognized and addressed early. Cervical spine anomalies and extraocular muscle disorders must be ruled out, and appropriate physical therapy is undertaken at an early age.
Diagnosis Routine surveillance of an infant’s head shape should be incorporated into periodic well-child visits during the first year of life [1]. The presence of a cranial vault asymmetry during the early postnatal period should alert the examiner to the possibility of craniosynostosis. Early referral to a craniofacial or neurosurgical specialist is indicated when there is a persistent cranial asymmetry or a skeletal pattern consistent with synostosis. Understanding the differences between craniosynostosis and positional plagiocephaly is important, because craniosynostosis usually requires surgical reshaping of the cranial vault to increase intracranial volume and correct the dysmorphic shape. Conversely, positional plagiocephaly is a disorder that does not require surgery in most cases. A diagnostic dilemma for pediatricians frequently occurs because the two conditions may seem to have similar morphologic features. As a result, an important initial step in the management of abnormal head shape is the determination of an accurate diagnosis separating synostotic from nonsynostotic plagiocephaly. Diagnosis of positional plagiocephaly primarily is based on a thorough history and physical examination and is confirmed radiographically. History taking should include details of the parental medical history and family history, the antenatal and birth histories of the child, giving consideration to any exposures or complications of the pregnancy, and a current medical history for the infant. A detailed history often provides information that strongly suggests the diagnosis even before the actual clinical evaluation. For example, when an infant presents with positional plagiocephaly, parents frequently report that the child’s head shape was well rounded at the time of birth and the asymmetry subsequently developed
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during the first 3 to 6 months of life. By contrast, patients with craniosynostosis-related plagiocephaly have a history of cranial deformity noticed immediately or shortly after birth. This significant difference is consistent with the fact that craniosynostosis is an intrauterine event, with the deformity starting during fetal development, and plagiocephaly secondary to repetitive positioning occurs only after external forces have had ample time to mold the cranium during early postnatal growth. Infants with positional posterior plagiocephaly frequently present with a characteristic, recognizable cranial vault morphology that is highly suggestive, if not diagnostic, for the condition. Examiners who are familiar with the specific asymmetry typically encountered in positional plagiocephaly are able to differentiate it from the dysmorphic pattern associated with lambdoid suture craniosynostosis (Figs. 1 and 2). On clinical examination, patients with benign positional skull molding (ie, positional plagiocephaly) exhibit occipitoparietal flattening on the side of the posterior cranial vault affected by external forces (eg, repetitive sleep positioning). At the same time, ipsilateral frontal bossing and anterior displacement of the ear on the affected side are found. The morphologic pattern is consistent with a flexible cranial
Fig. 1. Illustration of cranial vault dysmorphology characteristic of posterior positional plagiocephaly. Postnatal external forces, such as repetitive sleep positioning, cause unilateral occipitoparietal flattening. Because the sutures are open and the cranial vault complex is flexible, all of the structures on the affected side are displaced anteriorly. Additional findings include ipsilateral frontal bossing and forward displacement of the ear. The outline of the cranial vault, as viewed from above, develops a form that resembles a parallelogram.
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Fig. 2. Bird’s-eye view of a child with benign positional skull molding (ie, positional plagiocephaly) secondary to repetitive sleep positioning. Three key findings are present on clinical examination: unilateral occipitoparietal flattening, ipsilateral frontal bossing, and ipsilateral forward displacement of the ear.
vault that allows forward movement of all structures on the side subjected to external deformational forces. The head shape associated with positional plagiocephaly has been described as having a parallelogram deformity when examined from above (bird’seye view) [13]. By comparison, the cranial vault deformity seen with lambdoid suture craniosynostosis is characterized by distinctly different features (Fig. 3, Table 1). When a lambdoid suture is absent, there is arrested skeletal growth across the affected occipital and parietal bones, which also results in significant flattening or posterior plagiocephaly, but that is where the similarities to positional plagiocephaly end. In lambdoid synostosis, the arrested growth causes retraction of the ipsilateral forehead. The cranial base involvement seen in synostosis also causes posteriorinferior displacement of the ipsilateral ear. Because of compensatory growth that occurs at the sutures that remain open, contralateral frontal bossing is seen. From bird’s-eye view, the deformity is often described as having a trapezoidal shape (Fig. 3). Although the diagnosis of positional plagiocephaly primarily is made on the clinical evaluation of the presenting dysmorphology, confirmatory radiographic studies are required. After careful clinical examination is performed, a complete skull series of plain radiographs is usually sufficient to establish definitively the diagnosis and exclude the possibility of craniosynostosis (Fig. 4). A diagnostic, highquality study permits adequate visualization of all su-
Fig. 3. Illustration of cranial vault dysmorphology characteristic of posterior plagiocephaly secondary to unilateral lambdoid suture craniosynostosis. In this example, arrested development across the right lambdoid suture causes flattening of the occipital and parietal bones. The lack of cranial growth on the affected side also produces retraction of the forehead on the right (ipsilateral) side, and the right ear is displaced posteriorly and inferiorly when compared with the left. Compensatory overgrowth also occurs at the sutures that remain open, which causes contralateral frontal bossing. From a bird’s-eye view, the cranial vault may take on the shape of a trapezoid.
ture areas to establish that the cranial vault sutures are patent. In cases in which plain radiographic images do not permit conclusive evaluation of the sutures, the use of a complete craniofacial CT scan is indicated (Fig. 5). CT evaluation allows a more detailed view of the suture regions and provides additional information about the three-dimensional skeletal morphology. Such detailed studies are used more commonly for surgical planning in patients with surgical problems (ie, synostosis) but may also be of value in cases of
Table 1 Nonsynostotic versus synostotic plagiocephaly Positional plagiocephaly
Lambdoid synostosis
Occipitoparietal flattening Ipsilateral frontal bossing Forward displacement of the ipsilateral ear No bony ridging
Occipitoparietal flattening Ipsilateral frontal flattening Posterior displacement of the ipsilateral ear Bony ridging along involved suture region
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Fig. 4. (A – D) A complete skull series of plain radiographs is frequently adequate imaging for confirmation of the diagnosis of positional plagiocephaly. Diagnostic films provide a clear view of all open major cranial vault suture regions.
suspected positional plagiocephaly, in which the plain film study results are equivocal. In addition to confirming the status of the cranial vault sutures, radiographic imaging studies also provide insights regarding the morphology of the cranial base. Lo et al [14] detailed changes in the endocranial base seen in unilateral coronal and unilateral lambdoid synostosis and compared them to those of skull molding. They made the observation that the endocranial base of infants with craniosynostosis was likely to deviate from the 0°- to 180°anteroposterior axis by more than 7° toward the affected suture, whereas this was not the case in positional plagiocephaly. Although current radiographic imaging techniques have become increasingly refined, allowing for detailed visualization of the cranial anatomy (including the sutures), wide variation remains regarding the radiographic descriptions used for positional plagiocephaly and craniosynostosis. At some medical centers, radiologists continue to use outdated and confusing terminology, such as ‘‘fibrous synostosis’’
or ‘‘impending synostosis,’’ to describe cranial vault sutures that otherwise appear patent on a radiograph or CT scan. The idea is that the suture appears radiographically normal but somehow will demonstrate abnormal physiology. We know that the premature fusion of cranial vault sutures (ie, craniosynostosis) is an intrauterine event that is present at birth when it occurs. Unfortunately, some centers still use this type of inappropriate terminology, which has an impact on the clinical decision making related to patients with abnormal head shape. The result may be confusion among health care providers and even surgical intervention for a patient with a nonsurgical problem (ie, positional plagiocephaly). As recently as the 1990s, posterior positional plagiocephaly was misdiagnosed frequently and treated inappropriately as unilateral lambdoid synostosis. This was realized at many centers with increasing numbers of lambdoid synostosis cases being treated and what some surgeons termed ‘‘functional lambdoid synostosis’’ when the histopathologic diagnosis did not support true synostosis [11,13]. From a chronologic standpoint,
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Fig. 5. (A – D) Complete craniofacial CT scan with three-dimensional reconstructions for evaluation of a cranial vault asymmetry. The study reveals that all of the cranial vault sutures are open, which rules out craniosynostosis. CT imaging provides the most detailed view of the sutures and quantitative data about the cranial vault morphology.
this activity coincided with the initiation of the American Academy of Pediatrics’ ‘‘Back to Sleep’’ campaign. We know that the cranial asymmetry of unilateral lambdoid synostosis is distinct from that of posterior positional plagiocephaly; perhaps more importantly, we recognize positional plagiocephaly as a nonsurgical problem in most patients [1,6,7,13 – 19].
Treatment The treatment of positional plagiocephaly is generally nonsurgical. If craniosynostosis is confirmed, then reconstruction of the cranial vault to increase intracranial volume and establish a more normal morphology is completed using a team approach with a pediatric neurosurgeon and pediatric craniofacial surgeon. Positional plagiocephaly does not result in restriction of brain growth. As a result,
there are no associated negative functional neurologic consequences, so operative intervention is not indicated. Despite the lack of neurologic insult, there may be a significant skeletal deformity that must be addressed. When the degree of skeletal asymmetry is mild and is detected early in life, providing parental instruction about alternating head movements and avoiding repetitive positioning is usually the most appropriate initial measure. Parents are instructed to monitor and encourage frequent changes in their children’s head position throughout the course of the day and avoid repetitive sleep positioning. Repositioning of a baby’s head while in carriers and car seats is an important component of this regimen. Parents are also taught to lay infants down to sleep in the supine position and alternate the right and left occipital regions. When awake, children should be fed from the right and left sides to discourage the
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development of a voluntary position preference. Supervised ‘‘tummy time’’ should be encouraged once infants are capable of lifting their head and have acceptable arm strength. Generally, these guidelines should be followed until the physician is confident that the deformity is improving or until infants are sitting and crawling consistently and spending less time on their back. Infants who present with positional skull molding and moderate to severe plagiocephalic skull deformity benefit from treatment with a custom-made cranial orthotic device (Fig. 6). Orthotics are of two basic varieties: (1) custom-fitted molding helmets that facilitate passive cranial reshaping and (2) dynamic or ‘‘active’’ orthotic cranioplasty devices that use the growth potential of the brain and skull and mild constrictive forces to mold the cranial skeleton (eg, DOC Band, Cranial Technologies, Tempe, Arizona; STAR Band, Orthomerica, Newport Beach, California). Clarren et al [9] first reported the use of custom helmet therapy for infants with CMT and positional plagiocephaly. Others have since described the use of ‘‘dynamic’’ and passive devices with similar efficacy [15,19 – 21]. The idea is to apply direct pressure or limit further growth and deformity in the areas of frontal and occipital prominence, while the helmet is relieved over adjacent flattened areas to allow for ongoing brain growth to drive cranial vault expansion and remodeling. Physicians recommend that the orthotic be worn for 22 to 23 hours a day to obtain
Fig. 6. A child with positional plagiocephaly undergoing nonsurgical treatment with the use of a custom-made cranial orthotic device.
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maximal improvement in cranial shape. Progress is followed weekly by an orthotist or physical therapist, at which time skull growth and incremental correction of the deformity are evaluated. The inner lining is modified accordingly or, in situations that involve rapid growth or correction, a new band is fabricated. The greatest benefit from the use of custom-made cranial orthotic devices is achieved when they are used before 1 year of life and ideally when they are initiated before 6 months of age [22]. This benefit arises because of the propulsive rate of brain growth during this period, which drives outward expansion and remodeling of the cranial vault. Usually, a cranial orthotic is used for a 4-month period before the child outgrows it and the band loses its ability to effect cranial morphology. Because the speed of brain expansion slows down after 1 year of life, treatment performed between 12 and 18 months of age usually is associated with diminished reshaping. By the time a child is 18 to 24 months old, the benefit of cranial orthotic treatment is limited, and after 24 months, minimal to no changes are likely. Cranial orthotic devices produce the most significant improvements in the position of the cranial vault segments to round out the shape of the head. Changes in auricular position are more limited, and even patients who achieve excellent correction of the cranial shape often demonstrate persistent asymmetry in their ear alignment and position. The same is true when an underlying skull base asymmetry is noted. Successful management of positional plagiocephaly requires that any contributing factors be addressed at the same time that the cranial asymmetry is treated. In patients with CMT, simultaneous physical therapy and parent-directed exercises are prescribed. If a patient demonstrates an abnormal head tilt that is related to extraocular muscle imbalance or cervical spine anomalies, then pediatric ophthalmologic consultation and pediatric neurosurgical evaluation are undertaken, respectively. Surgical treatment of infants with positional plagiocephaly is not undertaken. In rare instances, a child with an untreated skull deformity demonstrates severe residual asymmetry after cranial growth is finished. Fortunately, this is a rare occurrence and usually is associated with a previous history that involves repetitive positioning for prolonged periods of time. For example, a child with a complicated medical situation and history of prolonged bed rest during early life may have developed a severe skull asymmetry that went untreated. Although these residual deformities do not affect brain function, they may be severe and cause significant negative psychosocial consequences. Surgical intervention is
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undertaken with a combined pediatric neurosurgical and pediatric craniofacial approach similar to that used in the management of craniosynostosis.
Summary Plagiocephaly is the result of many causes. Clinicians must be well versed in the differential diagnosis of plagiocephaly to determine if treatment should be surgical or nonsurgical. Craniosynostosis is a fetal malformation and should be diagnosed and treated relatively early in a child’s life with cranio-orbital decompression and reshaping. Positional plagiocephaly is a nonsynostotic condition in which there is a deformation of the cranial vault in the presence of otherwise open, normally functioning sutures. The reported incidence of positional plagiocephaly has increased with the implementation of ‘‘Back to Sleep’’ guidelines for the prevention of SIDS. Pediatricians also have maintained an increased awareness of the importance of early referral for evaluation of abnormal head shape during infancy. Positional plagiocephaly is a cranial vault deformation in the presence of open cranial vault sutures with no negative neurologic consequences. A distinct morphologic pattern and patent cranial sutures noted on confirmatory radiographic studies distinguish positional plagiocephaly from abnormal head shapes secondary to craniosynostosis. Management consists of conservative (nonsurgical) means, depending on the extent of the cranial asymmetry and any contributing etiologic factors.
References [1] Kane AA, Mitchell LE, Craven KP, Marsh JL. Observations on a recent increase in plagiocephaly without synostosis. Pediatrics 1996;97:877 – 85. [2] Cohen Jr MM. The etiology of craniosynostosis. In: Cohen Jr MM, editor. Craniosynostosis: diagnosis, evaluation, and management. New York7 Raven Press; 1986. p. 65 – 6. [3] Dunn PM. Congenital postural deformities. Br Med Bull 1976;32:71 – 6. [4] Persing J, James H, Swanson J, Kattwinkel J. Prevention and management of positional skull deformities in infants. Pediatrics 2003;112:199 – 202. [5] Cohen Jr MM. Craniostenosis and syndromes with craniosynostosis: Incidence, genetics, penetrance, variability, and new syndrome updating. Birth Defects 1979;15:13 – 63.
[6] AAP Taskforce. Positioning and SIDS. Pediatrics 1992;89:1120 – 6. [7] Posnick JC. Posterior plagiocephaly: unilateral lambdoid synostosis and skull molding. In: Posnick JC, editor. Craniofacial and maxillofacial surgery in children and young adults. Philadelphia7 WB Saunders; 2000. p. 231 – 48. [8] Boere-Boonekamp MM, van der Linden-Kuiper C. Positional preference/prevalence in infants and followup after two years. Pediatrics 2001;107:339 – 43. [9] Clarren SK, Smith DW, Hanson JW. Helmet treatment for plagiocephaly and congenital muscular torticollis. J Pediatr 1979;94:43 – 6. [10] Clarren SK. Plagiocephaly and torticollis: etiology, natural history, and helmet treatment. J Pediatr 1981; 98:92 – 5. [11] Slate RK, Posnick JC, Armstrong DC, et al. Cervical spine subluxation associated with congenital muscular torticollis and craniofacial anomaly. Plast Reconstr Surg 1993;91:7. [12] Golden KA, Beals SP, Littlefield TR, Pomatto JK. Sternocleidomastoid imbalance versus congenital muscular torticollis: their relationship to positional plagiocephaly. Cleft Palate Craniofac J 1999;36:256 – 61. [13] Huang MHS, Gruss JS, Clarren SK, Mouradain WE, Cunningham ML, Roberts TS, et al. The differential diagnosis of posterior plagiocephaly: true lambdoid synostosis versus positional molding. Plast Reconstr Surg 1996;98:765 – 76. [14] Lo L, Marsh JL, Pilgram TK, Vannier MW. Plagiocephaly: differential diagnosis based on endocranial morphology. Plast Reconstr Surg 1996;97:282 – 91. [15] Pollack IF, Fasick P. Diagnosis and management of posterior plagiocephaly. Pediatrics 1997;99:180 – 5. [16] Hansen M, Mulliken JB. Frontal plagiocephaly. Clin Plast Surg 1994;21:543 – 53. [17] Bruneteau RJ, Mulliken JB. Frontal plagiocephaly: synostotic, compensational, or deformational. Plast Reconstr Surg 1992;89:21 – 31. [18] Argenta LC, David LR, Wilson JA, Bell WO. An increase in infant cranial deformity with supine sleeping position. J Craniofac Surg 1996;7:5 – 11. [19] Turk AE, McCarthy JG, Thorne CHM, Wisoff JH. The ‘‘back to sleep campaign’’ and deformational plagiocephaly: is there cause for concern? J Craniofac Surg 1996;7:12 – 8. [20] Loveday BPT, de Chalain TB. Active counterpositioning or orthotic device to treat positional plagiocephaly? J Craniofac Surg 2001;12:308 – 13. [21] Vles JSH, Colla C, Weber JW, Beuls E, Wilmink J, Kingma H. Helmet versus nonhelmet treatment in nonsynostotic positional plagiocephaly. J Craniofac Surg 2000;11:572 – 4. [22] Kelly KM, Littlefield TR, Pomatto JK, Ripley CE, Beals SP, Joganic EF. Importance of early recognition and treatment of deformational plagiocephaly with orthotic cranioplasty. Cleft Palate Craniofac J 1999;36: 127 – 30.
Positional plagiocephaly: evaluation and management John Caccamese, DMD, MDa, Bernard J. Costello, DMD, MDb, Ramon L. Ruiz, DMD, MDc,*, Ann M. Ritter, MDd a
Department of Oral and Maxillofacial Surgery, University of Maryland Medical System, 419 West Redwood Street, Suite 410, Baltimore, MD 21043, USA b Department of Oral and Maxillofacial Surgery, University of Pittsburgh Medical Center, Magee-Women’s Hospital, Children’s Hospital of Pittsburgh, 3471 Fifth Avenue, Suite 1112, Pittsburgh, PA 15213, USA c Oral and Maxillofacial Surgery/Pediatric Craniofacial Surgery, Southwest Florida Oral and Facial Surgery, 5285 Summerlin Road, Suite 101, Fort Meyers, FL 33919, USA d Department of Pediatric Neurosurgery, Children’s Hospital of North Carolina, University of North Carolina at Chapel Hill, 148 Burnett-Womack Building, Chapel Hill, NC 27599, USA
Plagiocephaly is a clinically descriptive term for an oblique or asymmetric head shape that does not imply a definitive diagnosis. Throughout the scientific literature, however, plagiocephaly frequently has been used broadly to describe asymmetries of the anterior or posterior cranial vault, often without differentiating between synostotic (ie, fused sutures) and nonsynostotic (ie, patent suture) deformities [1]. Understanding the heterogenous nature of plagiocephaly is critical because treatments vary dramatically depending on the specific underlying diagnosis. Depending on the specific cause of the cranial vault deformity, the required management may range from observation to more extensive intervention, including major surgery for reconstruction of the cranial vault. Congenital anomalies may be classified into several basic categories: (1) malformations, which result during embryogenesis (eg, craniosynostosis) and are morphologic defects of an organ, part of an organ, or a larger area of the body that result from an intrinsically abnormal developmental process, (2) deformations, which occur later in fetal life or postnatally and are alterations in the form or position of a previously normally formed structure secondary to nondisruptive me-
* Corresponding author. E-mail address: [email protected] (R.L. Ruiz).
chanical forces (eg, positional plagiocephaly), and (3) disruptions, which are morphologic defects of an organ or part of an organ that result from the breakdown or interference with an originally normal structure (eg, amniotic band disruptions) [2]. During the first 2 years of life, brain growth occurs at a rapid rate. In the newborn, the presence of open cranial vault sutures (eg, metopic, coronal, sagittal, and lambdoid) creates a flexible complex of cranial bones that allows the brain to expand. This flexibility of the cranium, which allows unrestricted brain development, also may permit the cranial vault to be deformed. ‘‘Positional plagiocephaly’’ is defined as a cranial vault asymmetry in the presence of patent cranial vault sutures. This type of skull molding or deformational plagiocephaly is commonly seen in neonates and infants, and previous intrauterine constraint, the birthing process, or repetitive sleep positioning all can contribute to the severity of the cranial vault asymmetry. In contrast, craniosynostosis is a malformation that occurs almost universally during fetal development and is defined as the premature fusion of a cranial vault suture or sutures that results in arrested skeletal growth and a head shape abnormality. The different forms of craniosynostosis each produce unique craniofacial dysmorphologies. Clinicians must be able to differentiate between the dysmorphic craniofacial patterns produced by
1042-3699/04/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/j.coms.2004.08.006
oralmaxsurgery.theclinics.com
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these different causes. This article presents the current diagnostic approach, differential diagnosis, and treatment options for positional plagiocephaly.
Incidence and etiology of positional plagiocephaly During the first few days of life, cranial molding that resulted from the passage of the child’s head through the birth canal or early decent into the mother’s pelvis is frequently noted. This asymmetry usually resolves spontaneously within the first several weeks of life in most infants. No treatment is required other than routine observation during wellbaby check-ups. Another group of children demonstrates normocephalic morphology after birth but subsequently develops cranial vault asymmetry during early postnatal development. This positional plagiocephaly is the result of postnatal external forces, usually from repetitive sleep positioning, that act on a flexible cranium. Previous reports have estimated the incidence of positional plagiocephaly as low as 1:300 and as high as 1:2 infants under the age of 1 year [3,4]. In contrast, the incidence of lambdoid suture craniosynostosis, which also produces posterior plagiocephaly, is approximately 1:150,000 live births [2]. Unilateral coronal craniosynostosis is another relevant condition because it produces anterior cranial vault asymmetry that may be confused with deformational changes. It has a relative incidence of approximately 1:10,000 live births [5]. In 1992, the American Academy of Pediatrics started the ‘‘Back to Sleep’’ campaign, which recommended that infants be placed on their sides or backs during sleep to reduce the risk of sudden infant death syndrome (SIDS) [6]. Since instituting the campaign in 1992, the incidence of SIDS has decreased by 40%. At the same time, however, a significant increase in the number of children referred for management of posterior plagiocephaly without synostosis was observed [7]. Early on, several centers reported a sudden increase in the number of unilateral lambdoid ‘‘synostosis’’ cases being seen. Later, it was realized that the increased number of referrals was actually repetitive sleep positioning that caused nonsynostotic posterior plagiocephaly [1,7]. Positional preference also has been recognized as a significant contributor to cranial asymmetry since the early 1990s. Positional preference merely refers to an infant or child’s preference in maintaining the head turned to one side most of the time. Active movements of the head to the opposite side are few, and passive mobility may be limited. Positional prefer-
ence may be associated with torticollis, ocular conditions, scoliosis of infancy, limited abduction of the contralateral hip, and foot abnormalities [8]. In a recent study performed in the Netherlands that involved a large cohort of patients, the prevalence of positional preference was noted to be 8.2% and was seen most commonly in children younger than 16 weeks of age. First-born children, premature children, and breech positioned infants were at the highest risk for positional preference. Supine sleeping positioning and repetitive positioning during feeding were positively correlated with positional preference [8]. Another potential contributing factor to positional plagiocephaly is congenital muscular torticollis (CMT). CMT is an abnormal head tilt that results from congenital tethering of one of the sternocleidomastoid muscles. The result of this unilateral muscular problem is a persistent aberrant head position that causes skull molding and asymmetry, which affect the anterior or posterior cranial vault. One theory regarding the cause of CMT has proposed that late intrauterine constraint leads to venous occlusion and damage of the sternocleidomastoid muscle [9,10]. This insult generally results in unilateral fibrosis and shortening of the sternocleidomastoid muscle. Other suggested causes include intrinsic malformations or ‘‘pseudo-tumors’’ of the sternocleidomastoid musculature, neurologic disorders, and hemiatrophy/hypertrophy [9,10]. Whatever the cause, the fetal head is molded while obliquely compressed by the muscle tethering. Consequently, contralateral deviation of the chin, lateral neck flexion, and decreased range of motion are frequently noted on examination. In infants in whom CMT is severe, the cranial asymmetry becomes more pronounced in the first few months of life as the infant’s head is maintained in a relatively fixed position. On physical examination, head tilt, limited neck range of motion, and contralateral facial flattening should be noted. Persing et al [4] recommend the rotating chair test to aid in making the diagnosis of CMT associated with positional plagiocephaly. To perform this test, the examiner holds the infant while the parent keeps the infant’s interest. The examiner rotates in the chair and observes the infant’s range of neck motion. The difference in neck mobility toward and away from the affected side may aid in making the diagnosis of CMT [1]. Slate et al [11] noted asymptomatic cervical spine subluxations in half of their study population with CMT. This finding coincided with a 62% rate of difficult or breech deliveries. Whether these findings were the result of birth trauma or unfavorable intrauterine positioning was not clear.
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Other researchers have suggested a less severe variant of CMT called sternocleidomastoid imbalance, in which the position of the neck is not fixed but only intermittently tilted with a normal range of motion attributable to a weakened sternocleidomastoid. This condition may be more common than CMT and more amenable to physical therapy [12]. If left untreated, however, the resultant head deformity remains the same. When positional plagiocephaly is associated with CMT, it is imperative that it be recognized and addressed early. Cervical spine anomalies and extraocular muscle disorders must be ruled out, and appropriate physical therapy is undertaken at an early age.
Diagnosis Routine surveillance of an infant’s head shape should be incorporated into periodic well-child visits during the first year of life [1]. The presence of a cranial vault asymmetry during the early postnatal period should alert the examiner to the possibility of craniosynostosis. Early referral to a craniofacial or neurosurgical specialist is indicated when there is a persistent cranial asymmetry or a skeletal pattern consistent with synostosis. Understanding the differences between craniosynostosis and positional plagiocephaly is important, because craniosynostosis usually requires surgical reshaping of the cranial vault to increase intracranial volume and correct the dysmorphic shape. Conversely, positional plagiocephaly is a disorder that does not require surgery in most cases. A diagnostic dilemma for pediatricians frequently occurs because the two conditions may seem to have similar morphologic features. As a result, an important initial step in the management of abnormal head shape is the determination of an accurate diagnosis separating synostotic from nonsynostotic plagiocephaly. Diagnosis of positional plagiocephaly primarily is based on a thorough history and physical examination and is confirmed radiographically. History taking should include details of the parental medical history and family history, the antenatal and birth histories of the child, giving consideration to any exposures or complications of the pregnancy, and a current medical history for the infant. A detailed history often provides information that strongly suggests the diagnosis even before the actual clinical evaluation. For example, when an infant presents with positional plagiocephaly, parents frequently report that the child’s head shape was well rounded at the time of birth and the asymmetry subsequently developed
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during the first 3 to 6 months of life. By contrast, patients with craniosynostosis-related plagiocephaly have a history of cranial deformity noticed immediately or shortly after birth. This significant difference is consistent with the fact that craniosynostosis is an intrauterine event, with the deformity starting during fetal development, and plagiocephaly secondary to repetitive positioning occurs only after external forces have had ample time to mold the cranium during early postnatal growth. Infants with positional posterior plagiocephaly frequently present with a characteristic, recognizable cranial vault morphology that is highly suggestive, if not diagnostic, for the condition. Examiners who are familiar with the specific asymmetry typically encountered in positional plagiocephaly are able to differentiate it from the dysmorphic pattern associated with lambdoid suture craniosynostosis (Figs. 1 and 2). On clinical examination, patients with benign positional skull molding (ie, positional plagiocephaly) exhibit occipitoparietal flattening on the side of the posterior cranial vault affected by external forces (eg, repetitive sleep positioning). At the same time, ipsilateral frontal bossing and anterior displacement of the ear on the affected side are found. The morphologic pattern is consistent with a flexible cranial
Fig. 1. Illustration of cranial vault dysmorphology characteristic of posterior positional plagiocephaly. Postnatal external forces, such as repetitive sleep positioning, cause unilateral occipitoparietal flattening. Because the sutures are open and the cranial vault complex is flexible, all of the structures on the affected side are displaced anteriorly. Additional findings include ipsilateral frontal bossing and forward displacement of the ear. The outline of the cranial vault, as viewed from above, develops a form that resembles a parallelogram.
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Fig. 2. Bird’s-eye view of a child with benign positional skull molding (ie, positional plagiocephaly) secondary to repetitive sleep positioning. Three key findings are present on clinical examination: unilateral occipitoparietal flattening, ipsilateral frontal bossing, and ipsilateral forward displacement of the ear.
vault that allows forward movement of all structures on the side subjected to external deformational forces. The head shape associated with positional plagiocephaly has been described as having a parallelogram deformity when examined from above (bird’seye view) [13]. By comparison, the cranial vault deformity seen with lambdoid suture craniosynostosis is characterized by distinctly different features (Fig. 3, Table 1). When a lambdoid suture is absent, there is arrested skeletal growth across the affected occipital and parietal bones, which also results in significant flattening or posterior plagiocephaly, but that is where the similarities to positional plagiocephaly end. In lambdoid synostosis, the arrested growth causes retraction of the ipsilateral forehead. The cranial base involvement seen in synostosis also causes posteriorinferior displacement of the ipsilateral ear. Because of compensatory growth that occurs at the sutures that remain open, contralateral frontal bossing is seen. From bird’s-eye view, the deformity is often described as having a trapezoidal shape (Fig. 3). Although the diagnosis of positional plagiocephaly primarily is made on the clinical evaluation of the presenting dysmorphology, confirmatory radiographic studies are required. After careful clinical examination is performed, a complete skull series of plain radiographs is usually sufficient to establish definitively the diagnosis and exclude the possibility of craniosynostosis (Fig. 4). A diagnostic, highquality study permits adequate visualization of all su-
Fig. 3. Illustration of cranial vault dysmorphology characteristic of posterior plagiocephaly secondary to unilateral lambdoid suture craniosynostosis. In this example, arrested development across the right lambdoid suture causes flattening of the occipital and parietal bones. The lack of cranial growth on the affected side also produces retraction of the forehead on the right (ipsilateral) side, and the right ear is displaced posteriorly and inferiorly when compared with the left. Compensatory overgrowth also occurs at the sutures that remain open, which causes contralateral frontal bossing. From a bird’s-eye view, the cranial vault may take on the shape of a trapezoid.
ture areas to establish that the cranial vault sutures are patent. In cases in which plain radiographic images do not permit conclusive evaluation of the sutures, the use of a complete craniofacial CT scan is indicated (Fig. 5). CT evaluation allows a more detailed view of the suture regions and provides additional information about the three-dimensional skeletal morphology. Such detailed studies are used more commonly for surgical planning in patients with surgical problems (ie, synostosis) but may also be of value in cases of
Table 1 Nonsynostotic versus synostotic plagiocephaly Positional plagiocephaly
Lambdoid synostosis
Occipitoparietal flattening Ipsilateral frontal bossing Forward displacement of the ipsilateral ear No bony ridging
Occipitoparietal flattening Ipsilateral frontal flattening Posterior displacement of the ipsilateral ear Bony ridging along involved suture region
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Fig. 4. (A – D) A complete skull series of plain radiographs is frequently adequate imaging for confirmation of the diagnosis of positional plagiocephaly. Diagnostic films provide a clear view of all open major cranial vault suture regions.
suspected positional plagiocephaly, in which the plain film study results are equivocal. In addition to confirming the status of the cranial vault sutures, radiographic imaging studies also provide insights regarding the morphology of the cranial base. Lo et al [14] detailed changes in the endocranial base seen in unilateral coronal and unilateral lambdoid synostosis and compared them to those of skull molding. They made the observation that the endocranial base of infants with craniosynostosis was likely to deviate from the 0°- to 180°anteroposterior axis by more than 7° toward the affected suture, whereas this was not the case in positional plagiocephaly. Although current radiographic imaging techniques have become increasingly refined, allowing for detailed visualization of the cranial anatomy (including the sutures), wide variation remains regarding the radiographic descriptions used for positional plagiocephaly and craniosynostosis. At some medical centers, radiologists continue to use outdated and confusing terminology, such as ‘‘fibrous synostosis’’
or ‘‘impending synostosis,’’ to describe cranial vault sutures that otherwise appear patent on a radiograph or CT scan. The idea is that the suture appears radiographically normal but somehow will demonstrate abnormal physiology. We know that the premature fusion of cranial vault sutures (ie, craniosynostosis) is an intrauterine event that is present at birth when it occurs. Unfortunately, some centers still use this type of inappropriate terminology, which has an impact on the clinical decision making related to patients with abnormal head shape. The result may be confusion among health care providers and even surgical intervention for a patient with a nonsurgical problem (ie, positional plagiocephaly). As recently as the 1990s, posterior positional plagiocephaly was misdiagnosed frequently and treated inappropriately as unilateral lambdoid synostosis. This was realized at many centers with increasing numbers of lambdoid synostosis cases being treated and what some surgeons termed ‘‘functional lambdoid synostosis’’ when the histopathologic diagnosis did not support true synostosis [11,13]. From a chronologic standpoint,
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Fig. 5. (A – D) Complete craniofacial CT scan with three-dimensional reconstructions for evaluation of a cranial vault asymmetry. The study reveals that all of the cranial vault sutures are open, which rules out craniosynostosis. CT imaging provides the most detailed view of the sutures and quantitative data about the cranial vault morphology.
this activity coincided with the initiation of the American Academy of Pediatrics’ ‘‘Back to Sleep’’ campaign. We know that the cranial asymmetry of unilateral lambdoid synostosis is distinct from that of posterior positional plagiocephaly; perhaps more importantly, we recognize positional plagiocephaly as a nonsurgical problem in most patients [1,6,7,13 – 19].
Treatment The treatment of positional plagiocephaly is generally nonsurgical. If craniosynostosis is confirmed, then reconstruction of the cranial vault to increase intracranial volume and establish a more normal morphology is completed using a team approach with a pediatric neurosurgeon and pediatric craniofacial surgeon. Positional plagiocephaly does not result in restriction of brain growth. As a result,
there are no associated negative functional neurologic consequences, so operative intervention is not indicated. Despite the lack of neurologic insult, there may be a significant skeletal deformity that must be addressed. When the degree of skeletal asymmetry is mild and is detected early in life, providing parental instruction about alternating head movements and avoiding repetitive positioning is usually the most appropriate initial measure. Parents are instructed to monitor and encourage frequent changes in their children’s head position throughout the course of the day and avoid repetitive sleep positioning. Repositioning of a baby’s head while in carriers and car seats is an important component of this regimen. Parents are also taught to lay infants down to sleep in the supine position and alternate the right and left occipital regions. When awake, children should be fed from the right and left sides to discourage the
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development of a voluntary position preference. Supervised ‘‘tummy time’’ should be encouraged once infants are capable of lifting their head and have acceptable arm strength. Generally, these guidelines should be followed until the physician is confident that the deformity is improving or until infants are sitting and crawling consistently and spending less time on their back. Infants who present with positional skull molding and moderate to severe plagiocephalic skull deformity benefit from treatment with a custom-made cranial orthotic device (Fig. 6). Orthotics are of two basic varieties: (1) custom-fitted molding helmets that facilitate passive cranial reshaping and (2) dynamic or ‘‘active’’ orthotic cranioplasty devices that use the growth potential of the brain and skull and mild constrictive forces to mold the cranial skeleton (eg, DOC Band, Cranial Technologies, Tempe, Arizona; STAR Band, Orthomerica, Newport Beach, California). Clarren et al [9] first reported the use of custom helmet therapy for infants with CMT and positional plagiocephaly. Others have since described the use of ‘‘dynamic’’ and passive devices with similar efficacy [15,19 – 21]. The idea is to apply direct pressure or limit further growth and deformity in the areas of frontal and occipital prominence, while the helmet is relieved over adjacent flattened areas to allow for ongoing brain growth to drive cranial vault expansion and remodeling. Physicians recommend that the orthotic be worn for 22 to 23 hours a day to obtain
Fig. 6. A child with positional plagiocephaly undergoing nonsurgical treatment with the use of a custom-made cranial orthotic device.
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maximal improvement in cranial shape. Progress is followed weekly by an orthotist or physical therapist, at which time skull growth and incremental correction of the deformity are evaluated. The inner lining is modified accordingly or, in situations that involve rapid growth or correction, a new band is fabricated. The greatest benefit from the use of custom-made cranial orthotic devices is achieved when they are used before 1 year of life and ideally when they are initiated before 6 months of age [22]. This benefit arises because of the propulsive rate of brain growth during this period, which drives outward expansion and remodeling of the cranial vault. Usually, a cranial orthotic is used for a 4-month period before the child outgrows it and the band loses its ability to effect cranial morphology. Because the speed of brain expansion slows down after 1 year of life, treatment performed between 12 and 18 months of age usually is associated with diminished reshaping. By the time a child is 18 to 24 months old, the benefit of cranial orthotic treatment is limited, and after 24 months, minimal to no changes are likely. Cranial orthotic devices produce the most significant improvements in the position of the cranial vault segments to round out the shape of the head. Changes in auricular position are more limited, and even patients who achieve excellent correction of the cranial shape often demonstrate persistent asymmetry in their ear alignment and position. The same is true when an underlying skull base asymmetry is noted. Successful management of positional plagiocephaly requires that any contributing factors be addressed at the same time that the cranial asymmetry is treated. In patients with CMT, simultaneous physical therapy and parent-directed exercises are prescribed. If a patient demonstrates an abnormal head tilt that is related to extraocular muscle imbalance or cervical spine anomalies, then pediatric ophthalmologic consultation and pediatric neurosurgical evaluation are undertaken, respectively. Surgical treatment of infants with positional plagiocephaly is not undertaken. In rare instances, a child with an untreated skull deformity demonstrates severe residual asymmetry after cranial growth is finished. Fortunately, this is a rare occurrence and usually is associated with a previous history that involves repetitive positioning for prolonged periods of time. For example, a child with a complicated medical situation and history of prolonged bed rest during early life may have developed a severe skull asymmetry that went untreated. Although these residual deformities do not affect brain function, they may be severe and cause significant negative psychosocial consequences. Surgical intervention is
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undertaken with a combined pediatric neurosurgical and pediatric craniofacial approach similar to that used in the management of craniosynostosis.
Summary Plagiocephaly is the result of many causes. Clinicians must be well versed in the differential diagnosis of plagiocephaly to determine if treatment should be surgical or nonsurgical. Craniosynostosis is a fetal malformation and should be diagnosed and treated relatively early in a child’s life with cranio-orbital decompression and reshaping. Positional plagiocephaly is a nonsynostotic condition in which there is a deformation of the cranial vault in the presence of otherwise open, normally functioning sutures. The reported incidence of positional plagiocephaly has increased with the implementation of ‘‘Back to Sleep’’ guidelines for the prevention of SIDS. Pediatricians also have maintained an increased awareness of the importance of early referral for evaluation of abnormal head shape during infancy. Positional plagiocephaly is a cranial vault deformation in the presence of open cranial vault sutures with no negative neurologic consequences. A distinct morphologic pattern and patent cranial sutures noted on confirmatory radiographic studies distinguish positional plagiocephaly from abnormal head shapes secondary to craniosynostosis. Management consists of conservative (nonsurgical) means, depending on the extent of the cranial asymmetry and any contributing etiologic factors.
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[6] AAP Taskforce. Positioning and SIDS. Pediatrics 1992;89:1120 – 6. [7] Posnick JC. Posterior plagiocephaly: unilateral lambdoid synostosis and skull molding. In: Posnick JC, editor. Craniofacial and maxillofacial surgery in children and young adults. Philadelphia7 WB Saunders; 2000. p. 231 – 48. [8] Boere-Boonekamp MM, van der Linden-Kuiper C. Positional preference/prevalence in infants and followup after two years. Pediatrics 2001;107:339 – 43. [9] Clarren SK, Smith DW, Hanson JW. Helmet treatment for plagiocephaly and congenital muscular torticollis. J Pediatr 1979;94:43 – 6. [10] Clarren SK. Plagiocephaly and torticollis: etiology, natural history, and helmet treatment. J Pediatr 1981; 98:92 – 5. [11] Slate RK, Posnick JC, Armstrong DC, et al. Cervical spine subluxation associated with congenital muscular torticollis and craniofacial anomaly. Plast Reconstr Surg 1993;91:7. [12] Golden KA, Beals SP, Littlefield TR, Pomatto JK. Sternocleidomastoid imbalance versus congenital muscular torticollis: their relationship to positional plagiocephaly. Cleft Palate Craniofac J 1999;36:256 – 61. [13] Huang MHS, Gruss JS, Clarren SK, Mouradain WE, Cunningham ML, Roberts TS, et al. The differential diagnosis of posterior plagiocephaly: true lambdoid synostosis versus positional molding. Plast Reconstr Surg 1996;98:765 – 76. [14] Lo L, Marsh JL, Pilgram TK, Vannier MW. Plagiocephaly: differential diagnosis based on endocranial morphology. Plast Reconstr Surg 1996;97:282 – 91. [15] Pollack IF, Fasick P. Diagnosis and management of posterior plagiocephaly. Pediatrics 1997;99:180 – 5. [16] Hansen M, Mulliken JB. Frontal plagiocephaly. Clin Plast Surg 1994;21:543 – 53. [17] Bruneteau RJ, Mulliken JB. Frontal plagiocephaly: synostotic, compensational, or deformational. Plast Reconstr Surg 1992;89:21 – 31. [18] Argenta LC, David LR, Wilson JA, Bell WO. An increase in infant cranial deformity with supine sleeping position. J Craniofac Surg 1996;7:5 – 11. [19] Turk AE, McCarthy JG, Thorne CHM, Wisoff JH. The ‘‘back to sleep campaign’’ and deformational plagiocephaly: is there cause for concern? J Craniofac Surg 1996;7:12 – 8. [20] Loveday BPT, de Chalain TB. Active counterpositioning or orthotic device to treat positional plagiocephaly? J Craniofac Surg 2001;12:308 – 13. [21] Vles JSH, Colla C, Weber JW, Beuls E, Wilmink J, Kingma H. Helmet versus nonhelmet treatment in nonsynostotic positional plagiocephaly. J Craniofac Surg 2000;11:572 – 4. [22] Kelly KM, Littlefield TR, Pomatto JK, Ripley CE, Beals SP, Joganic EF. Importance of early recognition and treatment of deformational plagiocephaly with orthotic cranioplasty. Cleft Palate Craniofac J 1999;36: 127 – 30.