Head and Neck Mechanics

Mechanically, the neck functions as an inverted pendulum with the weight balanced on top of the neck. The average weight of a human cadaver head dissected at C3 weight approximately 4 - 4.5 kg (On line ref: http://danny.oz.au/anthropology/notes/human-head-weight.html). Neck muscles are active throughout the day to stabilise this weight over the trunk as well as enable functional movements of rotation, flexion and extension. The further the head is positioned away from the central normal resting position the greater the leaver arm and resulting demands on neck muscles to support the head.