label: Cervical C6/C7 vertebrae fusion
label_lc: cervical c6/c7 vertebrae fusion
description: "Fusion of cervical vertebrae at C6 and C7, caused by a failure in the normal segmentation or division of the cervical vertebrae during the early weeks of fetal development, leading to a short neck with a low hairline at the back of the head, and restricted mobility of the upper spine."