Guest Author - Marji Hajic
In ergonomics, you will frequently hear the term “neutral positioning”. Let’s clarify what this term means. This is part 1 of a 2 part series discussing the fingers, wrist and forearm. Part 2 will discuss the elbows, shoulder and neck.
According to the medical dictionary at thefreedictionary.com, the neutral position of the arm is a body position to be assumed that prevents cumulative trauma to the arm. It incorporates proper placement of the wrist, elbow, and shoulder.
The Importance of Neutral Positioning
Awkward positioning at your computer can increase pressure or stretch on the nerves or cause friction and strain as the tendons move through or around pulley systems. This can lead to chronic inflammation and pain. Being positioned in the more relaxed and neutral position can help ease strain on the body and improve your work comfort.
The fingers should be relaxed and slightly curved as if they are resting over a large ball. Many people tend to hold their fingers too straight. Holding the fingers rigidly stiff is actually quite stressful to the small muscles in the hand. Two common causes of awkward finger positioning include 1) finger nails that are too long causing the finger to straighten when activating the keyboard with the pad of the fingers and 2) tension or stress causing the computer operator to pound the keyboard.
For more information, see Typing Style - Repetitive Strain Injuries are NOT Just About the Keyboard.
Poor wrist positioning is often implicated in carpal tunnel syndrome and wrist tendinitis. Maintaining a neutral wrist position can be critical to comfortable typing. The neutral wrist position is with the wrist flat (not bent forward or back) and not angled side-to-side. For every fifteen degrees that the wrist is bent forward or back, increased pressure is placed on the nerve that runs through the carpal tunnel.
Common causes of wrist pain include 1) planting the wrist down on the desk or wrist rest in front of the keyboard and 2) a keyboard that is too small causing the wrist to angle toward the small finger when placing the fingers on the home keys.
For more information, see The Wrist & Repetitive Strain Injuries
Most computer stations position our forearms in the palm-down position. Neutral positioning is actually positioning with the forearm half-way between palm-up and palm-down (with the thumb up and the palms facing each other). To help you find this neutral position, hand your hand at the side of your body and then bend your elbow without rotating your forearm. If you are having forearm or elbow pain, you may want to look into using a keyboard or mouse that helps rotate your arm into more of a neutral rotation.
For more information, see my reviews of vertical mice.
The Evoluent Mouse
The 3M Vertical Mouse
Coming Next Week
Part 2 - Neutral Positioning of the Elbow, Shoulder & Head
Marji Hajic is an Occupational Therapist and a Certified Hand Therapist practicing in Santa Barbara, California. For more information on hand and upper extremity injuries, prevention and recovery, visit Hand Health Resources.