Plagiocephaly is a general term for cranial asymmetry, derived from the Greek
word roots, plagios, meaning "oblique, aslant" and kephalê,
meaning "head." Pathogenically, plagiocephaly can be classified as
synostotic, caused by abnormal sutural development, or deformational, caused
by external forces acting on the cranium. Synostotic plagiocephaly usually requires
surgical correction, whereas deformational plagiocephaly improves with crib
positioning and, more predictably, with a molding helmet.