This is a series on the causes of arm and hand pain. There is a checklist for you at the beginning of this series.

“Sit up straight!” your mother would correct you. It wasn’t only because you looked bad slumped over, she knew that it was bad for your back, probably because she suffered from back pain herself, but she didn’t know the effect on your arms and hands in this computer-oriented culture. This is going to be a damaged generation because of it.
The two most common postural causes of arm and hand pain are slumping and keeping the arms out in front on a keyboard or mouse or steering wheel. Both the rounded back and the forward-arm positions cause chest tension that leads to entrapment of nerves and blood vessels and the resulting pain in the upper extremities.

The primary postural stress is a slumped posture. Unfortunately, this is our popular casual American look. It is the equalizer, keeping you looking cool and relaxed, not standing out in the crowd. Sitting back on the base of your spine between your butt bones (sacrum and coccyx) rounds the lumbar vertebrae in the lowest part of your back outward toward the chair. These five chunky vertebrae are slightly wedge-shaped and are meant to stack up in a curve. In architecture, the arch is the strongest form of support. In the low back, this foundation structure supports the weight of the torso. When the curve is reversed as in the slumped posture, it disrupts the strength of the arch and forces the back to work harder to maintain the curve. Eventually the muscles get weak and vulnerable from the mild overuse, leading to shortening and tightening of chest and abdominal muscles, rounding the shoulders and forcing the head-forward, all of which can eventually lead to arm and hand pain.

The easy correction is to change the position of your lumbar spine to reestablish the natural curve, that strong architectural arch. To do that, rock your pelvis forward until you are positioned just in front of the highest part of the bones you sit on. When you do that, just like stacking kids blocks, the opposing curves of the mid-back and neck will naturally correct and you’ll be sitting straighter with your head back and balanced on top of your spine. It takes no effort to make this change, but your muscles will tire since they have become weak, returning you to the slumped position. Strengthening the core muscles and upper back muscles will help you maintain this as a comfortable posture and significantly reduce arm and hand pain.

A secondary postural stress is caused by the imbalance of the weight of the arms held out in front. The weight of the arms and hands plus the added weight of gravity puts a strain on the muscles of the upper back and shoulders as they try to hold that position. Pain is caused either by overuse of the muscles, lack of blood flow or distortion of nerve signals.

Positional stress is caused by any position that must be held for a while, like sitting at a computer or standing over a counter or a workbench. If there is a weight involved like holding the arms forward on the keyboard, controlling a tool, driving long distances or carrying a child the stress load is increased. The muscles work harder, the blood flow slows down with the tension, nutrients and oxygen don’t get delivered, waste products build up and you’ve got pain!

Posture and positional stress factors are evaluated in patients presenting with arm and hand pain at my Neuromuscular Therapy center near Boston.