Torticollis is a condition involving the neck that is often caused when the sternocleidomastoid (one of two muscles arising from the sternum and inner part of the clavicle, also called SCM) muscle is shorter than normal. This often results in a posture where the head tips toward the side of the short muscle, and rotates toward the opposite side.
Plagiocephaly (pley-jee-oh-'sef-uh-lee) is a term used to describe a malformation of the skull marked by an oblique slant to the head. More generally the term applies to any condition in which there is a misshapen skull including a flat spot on the back or side of the head. It is important to distinguish between an abnormal head shape caused by positional changes or deformation vs. an abnormal head shape caused by premature closure of the cranial sutures, known as craniosynostosis.