Neutral Posture

"Neutral Posture" refers to the resting position of each joint-the position in which there is the least tension or pressure on nerves, tendons, muscles and bones. It is also the position in which muscles are at their resting length-neither contracted nor stretched. Muscles at this length can develop maximum force most efficiently. One aspect of ergonomic redesign is the reworking of tools, work stations and processes to allow the worker's joints to remain in neutral position as much as possible.

(words in italics = definitions of postural terms)

Fingers

The fingers are gently curved, in their natural resting position. They are not spread apart. They are neither fully straightened out (extended) nor tightly curled (flexed).

Wrist

The wrist is in line with the forearm. It is neither bent up (extension) nor bent down (flexion). It is not bent towards the thumb (radial deviation) nor towards the little finger (ulnar deviation).

Forearm

The forearm rests with the thumb up. It is not rotated to make the palm face down (pronation) or up (supination).

Elbow

The elbow is in a neutral position when the angle between forearm and upper arm is close to a right angle (90 degrees). Some extension (up to 110 degrees) may be desirable.

Upper Arm

The upper arm hangs straight down. It is not elevated to the side (abduction), pulled across in front of the body (adduction), raised to the front (flexion) nor raised towards the back (extension).

Shoulder

The shoulders are in a resting position, neither hunched up nor pulled down, and not pulled forward or back.

Neck

The head is balanced on the spinal column. It is not tilted forward, back or to either side. It is not rotated to the left or right.

Back

The spine naturally assumes an S-shaped curve. The upper spine (thoracic region) is bent gently out; the lower spine (lumbar region) is bent gently in. These bends are called kyphosis and lordosis, respectively. The spine is not rotated (or twisted) to the left or right, and it is not bent to the left or right. Whether standing or sitting, the trunk does not bend forward (flexion) or backward (extension) by much (although a good backrest on a seat does allow extension).

Lower Body

Under conditions of weightlessness (e.g., in space travel), the lower body naturally assumes a neutral, fetal position-hip and knee joints somewhat bent. Thus, both seated and standing postures involve deviations from neutral posture.

Prepared by Nicholas Warren, MS, MAT, ScD and Timothy F. Morse, PhD, ErgoCenter, UConn Health Center, Farmington, CT.