Zergotech

ANATOMICAL REFERENCES

Understanding our anatomy and how we interact with our computers is key to the Freedom's design.

anatomical references woman hands calm

The starting point of ergonomics is understanding the anatomy of our bodies. For keyboards, this primarily your wrists, hands, and forearms.  Below is some general information about the various positions your hands can assume. We designed the Freedom to provide you with the most neutral and comfortable of these positions.


NOTE: The information provided on this website does not constitute medical advice. If you suffer from any pain, do consult your doctor. Please see our disclaimer concerning the use of our product and information contained on this website.

Vertical Movements

Wrist flexion is the position of the wrist reaching toward the inside of the forearm. This is a rare position which occurs when the keyboard is significantly lower than an accompanying wrist rest. Wrist extension occurs when the back of the hand reaches toward the outside of the forearm. This is a very common position for desktop users where the palms are rested on the desk while simultaneously reaching for the keys at a height. To maintain this position, forearm muscles would need to remain in a flexed position contributing to fatigue. Prolonged periods in this position can give rise to wear in the wrist's tendons and muscles.  A wrist neutral position places the hand aligned with the direction of the forearm. There is no flexion or contraction of muscles, and the tendons and bones of the hands remain in a relaxed and natural position.

Wrist Extension
wrist extension
Wrist Flexion
wrist flexion
Neutral Position
neutral position

Horizontal Movements

Radial Deviation is the posture of the hand turned inward in the direction of the thumb. Ulnar deviation is the position of the hand turned outward in the direction of the outer most “little” finger. These stressed positions occur when an over-reach is required to make a keystroke on a distant key. For example, three of the most commonly used keys are the Enter key, Backspace key and Delete key, all of which are located to the extreme right. Repeated deviations and extended periods of over-reach place excessive strain on the wrist and tendons, and are the largest source of RSI pain. A neutral and comfortable position aligns the fingers, wrist and forearms in a straight line.

Radial Deviation
radial deviation
Ulnar Deviation
ulnar deviation
Neutral Position
neutral position

Rotational Movements

Forearm Supination is the position of the forearm turned outward away from the body. This is a highly uncomfortable position, but one that rarely occurs at a desk. Forearm Pronation is the position of the forearm which is turned inward toward the body. This is a common position that is required to operate a flat structured keyboard. Pronation requires constant flexion and contraction of forearm muscles to maintain this position, exerting most of its pressure at the wrist. A neutral forearm position is one which resembles a handshake posture. It requires no flexion of forearm muscles, reducing general typing fatigue.

Forearm Pronation
forearm pronation
Forearm Supination
forearm supination
Neutral Position
neutral position

Asymmetrical Movements

Standard issue flat keyboards have asymmetrical offset rows of keys. This creates an asymmetry of finger reach. The “ASDF” row is the starting home row for typing. The bottom “ZXCV” row has keys that are exactly offset to the centre of the home row. The bottom row has symmetrical offset and does not cause fingers to over reach or under reach. The top two rows, however, namely the number row and the “QWERTY” row, are off asymmetrically offset from centre and to the left of the home row. Both sets of fingers on each hand are required to reach to the left. This means fingers on the left hand have a tighter and uncomfortable under-reach to the keys above, while the fingers on the right hand need to extend further with an over-reach to strike keys on those rows. The fingers and wrists struggle to deviate outward toward the pinky fingers. They have much less resistance to deviate inward toward the thumb.

Asymmetry of reach
asymmetry of reach
Phalange Deviation
phalange deviation