Another group of less common cephalic disorders are the CRANIOSTENOSES.
Craniostenoses are deformities of the skull caused by the premature fusion or joining together of the cranial sutures. Cranial sutures are fibrous joints that join the bones of the skull together. The nature of these deformities depends on which sutures are affected.
- BRACHYCEPHALY occurs when the coronal suture fuses prematurely, causing a shortened front-to-back diameter of the skull. The coronal suture is the fibrous joint that unites the frontal bone with the two parietal bones of the skull. The parietal bones form the top and sides of the skull.
- OXYCEPHALY is a term sometimes used to describe the premature closure of the coronal suture plus any other suture, or it may be used to describe the premature fusing of all sutures. Oxycephaly is the most severe of the craniostenoses.
- PLAGIOCEPHALY results from the premature unilateral fusion (joining of one side) of the coronal or lambdoid sutures. The lambdoid suture unites the occipital bone with the parietal bones of the skull. Plagiocephaly is a condition characterized by an asymmetrical distortion (flattening of one side) of the skull. It is a common finding at birth and may be the result of brain malformation, a restrictive intrauterine environment, or torticollis (a spasm or tightening of neck muscles).
- SCAPHOCEPHALY applies to premature fusion of the sagittal suture. The sagittal suture joins together the two parietal bones of skull. Scaphocephaly is the most common of the craniostenoses and is characterized by a long, narrow head.
- TRIGONOCEPHALY is the premature fusion of the metopic suture (part of the frontal suture which joins the two halves of the frontal bone of the skull) in which a V-shaped abnormality occurs at the front of the skull. It is characterized by the triangular prominence of the forehead and closely set eyes.