Craniosynostosis
Classification and external resources
Child with premature closure (craniosynostosis) of the lambdoid suture. Notice the swelling on the right side of the head
ICD-10	Q75.0
ICD-9	756.0
OMIM	218500
DiseasesDB	3160
eMedicine	med/2897
MeSH	D003398

Craniosynostosis,^[1] Craniosynostosis is a condition in which one or more of the fibrous sutures in an infant skull prematurely fuses. This results in restricted skull and brain growth. Because the brain can not expand in the direction of the fused suture, it is forced to grow in the direction of the open sutures, often resulting in an abnormal head shape and facial features. Some cases of craniosynostosis may result in increased pressure on the brain and developmental delays. It is estimated that craniosynostosis affects 1 in 2,000 live births. It can be the result of an inherited syndrome or sporadic. In sporadic cases, the cause is unknown.

Contents 1 Normal skull development 2 Diagnosis 2.1 Syndromes 2.2 Differential diagnosis 3 Treatment 4 Epidemiology 5 See also 6 References 7 External links

[edit] Normal skull development

In an infant, the skull is not one solid bone, it is bony plates separated by fibrous sutures. The infant's skull consists of the metopic suture,coronal sutures, sagittal suture, and lambdoid sutures. These sutures allow the skull to expand as an infant's brain develops. Over time these sutures eventually fuse into the solid skull.

[edit] Diagnosis

Physicians diagnose craniosynostosis through physical examination, plain x-rays, and CT scans. ^[2]

[edit] Syndromes

Craniosynostosis often occurs alone, however about 20% of cases are associated with syndromes. A syndrome is diagnosed by considering the presence of a variety of features, signs, and symptoms throughout the body. Genetic testing may be available to confirm the diagnosis of a specific syndrome. A family history of abnormal head shape can sometimes be found with genetic syndromes, though many syndromes are caused by new genetic mutations, and there is no family history of the disorder. ^[2]

The most common causes of syndromic craniosynostosis are Crouzon syndrome and Apert syndrome. However, there are over 150 syndromes associated with craniosynostosis. ^[2] The following table lists some of the craniosynostosis syndromes, as well as prominent additional symptoms that are found in these syndromes — this is not a comprehensive list of all symptoms that could occur within each syndrome. There is considerable overlap of symptoms between many of these syndromes, and clinical evaluation by a geneticist may be necessary to determine the most appropriate diagnosis.

The following syndromes are associated with fibroblast growth factor receptors:

Name of syndrome	Other signs and symptoms (along with craniosynostosis; may not all be present)	OMIM reference	Gene
Crouzon syndrome	wide-set, bulging eyes • beaked nose • flat face	123500	FGFR2, FGFR3
Apert syndrome	fused fingers or toes • flat midface	101200	FGFR2
Crouzonodermoskeletal syndrome	wide-set, bulging eyes • beaked nose • flat face • dark, velvety skin folds • spine abnormalities • benign growths in the jaw	134934	FGFR3
Jackson-Weiss syndrome	enlarged, bent big toes • flat midface	123150	FGFR1, FGFR2
Muenke syndrome	coronal synostosis • skeletal abnormalities of the hands or feet • hearing loss	602849	FGFR3
Pfeiffer syndrome	broad, short thumbs or big toes • webbed or fused fingers or toes	101600	FGFR1, FGFR2

In addition, the following syndromes have been identified:

Name of syndrome	Other signs and symptoms (along with craniosynostosis; may not all be present)	OMIM reference	Gene
Loeys-Dietz syndrome	wide-set eyes • split uvula or cleft palate • arterial tortuosity • aneurysms	609192	TGFBR1
Saethre-Chotzen syndrome	facial asymmetry • low frontal hairline • drooping eyelids • webbed fingers or toes • broad big toes	101400	TWIST1
Shprintzen-Goldberg syndrome	bulging eyes • flat face • hernias • long, thin fingers • developmental delay • mental retardation	182212	FBN1

[edit] Differential diagnosis

A separate cause of abnormal head shape is positional plagiocephaly — flattened or misshapen areas on the head that may develop due to sleeping position. While the appearance may look rather similar to craniosynostosis, the distinction is important. Positional plagiocephaly does not require surgery^[3] — treatment can be as simple as occasionally repositioning the child's head while sleeping or, in some cases, wearing a cranial band to mold the skull. ^[2] It has recently been discovered that using certain prescription drugs during pregnancy may lead to this disorder. (sertraline)

[edit] Treatment

Surgery is typically used to separate the fused sutures of the skull as well as to reshape the skull. To treat the cosmetic troubles, a combination of orthodontic and orthognathic surgery can be used to relieve some of the midface deficiency.

Typical surgery begins with a zigzag incision from ear to ear across the top of the head. The scar left by this type of incision makes the hair look more natural than that left by a straight incision would. Leroy clips are typically used to curtail bleeding, as cauterization would not result in an aesthetically pleasing result upon healing. Once the scalp is peeled back, pilot holes are drilled through the skull. These pilot holes are then connected, separating the skull into several pieces. Once reshaped, these pieces are placed back on the head (typically in an altered configuration) and held together by a combination of dissolving sutures, plates, and screws. These plates and screws are typically made of a copolymer composed of polyglycolic and polylactic acid and will break down into water and carbon dioxide within a year. Demineralized bone matrix or bone morphogenetic proteins are often used to fill gaps left by the expanded skull, encouraging the body to grow new bone in a process called intramembranous ossification. Once the hemostatic scalp clips are removed, sutures are again used to close the incision.

Newer approaches include minimally invasive endoscopic assisted removal of the closed suture followed by treatment with custom made molding helmets. These surgeries are associated with significantly less blood loss, swelling, hospital length of stay and pain. The results have been excellent in the majority of patients treated this way. Endoscopic surgery, however, is indicated only for very young infants(< 6 months of age). Older children require the more extensive surgery described above.

[edit] Epidemiology

The incidence of craniosynostosis has been described as 1 in 2500 live births.^[4] The earliest known case is a child dated to 530,000 BP found in Atapuerca Spain.^[5]

[edit] See also

• Cephalic disorder
• Positional plagiocephaly (flattened head syndrome)

[edit] References

[edit] External links

• Endoscopic Craniosynostosis Repair Video
• Information and support Cranio Kids- Families sharing and supporting
• Information and support Childrens Craniofacial Association

• Overview of craniosynostosis from Children's Hospital Boston
• Craniosynostosis — comprehensive overview (American Family Physician)
• Single Suture Craniosynostoses (The Craniofacial Center in Dallas, Texas)
• Craniosynostosis Photo Gallery at the University of Missouri Children's Hospital
• Information from CAPPS
• Information from Headlines]
• GeneReview/NIH/UW entry on FGFR-Related Craniosynostosis Syndromes

v • d • e Congenital malformations and deformations of musculoskeletal system / musculoskeletal abnormality (Q65-Q76, 754-756.3) Limb/ dysmelia Upper clavicle/shoulder: Cleidocranial dysostosis · Sprengel's deformity · Wallis Zieff Goldblatt syndrome hand deformity: Madelung's deformity · Clinodactyly Lower hip: Dislocation of hip/Hip dysplasia · Upington disease · Coxa valga · Coxa vara knee: Genu valgum · Genu varum foot deformity: Club foot · Flat feet · Pes cavus · Rocker bottom foot Either/both dactyly/digit: Polydactyly/Syndactyly (Webbed toes) · Arachnodactyly · Cenani Lenz syndactylism · Ectrodactyly · Brachydactyly reduction deficits/limb: Acheiropodia · ectromelia (Phocomelia, Amelia, Hemimelia) multiple joints: Arthrogryposis · Larsen syndrome · Rapadilino syndrome Craniofacial Craniosynostosis: Scaphocephaly · Oxycephaly · Trigonocephaly Craniofacial dysostosis: Crouzon syndrome · Hypertelorism · Hallermann-Streiff syndrome · Treacher Collins syndrome other: Macrocephaly · Platybasia · Craniodiaphyseal dysplasia · Dolichocephaly · Greig cephalopolysyndactyly syndrome · Plagiocephaly · Saddle nose Other axial spine: spinal curvature (Scoliosis) · Klippel-Feil syndrome · Spondylolisthesis · Spina bifida occulta ribs: Cervical rib · Bifid rib sternum: Pectus excavatum · Pectus carinatum joint navs: anat, non-congenital arthropathies/deformities/dorsopathies/soft tissue arthropathy/congenital, eponymous signs, proc