There are a couple of muscle groups in the neck that are important to know about in order to understand the damage that can be done by the standard ?hunched? laptop user. This will be especially applicable to regular users of PDAs. In the latter case, how many people do you see using a PDA properly, in terms of ergonomics, ie by holding the unit at face level ? Practically zero. The vast majority will contract their head and chest muscles with the standard ?head down? posture. Does this mean that we should not use these devices ? No, it does not. It simply means that we need to be aware of the possible side effects, and then perform routines afterwards that will help negate the bad effects.
The first group are called the ?SCALENE MUSCLES? and are situated at the side of the neck. We will discuss the second group, called the "STERNOCLEIDOMASTOID" muscles in the next post.When we move into a ?head forward posture?, some of these muscles contract ( they have to?..in order for the head to move ). Some other muscles at the rear are increased in length. So what is so important about the scalenes ?
We mentioned before that all nerves originate at the brain, and run down the spinal chord canal. At each spinal ?level? ( i.e. where two vertebrae join to form a foraminal hole ), nerves exit to the appropriate locations?hands, heart, kidneys etc. Some important nerves to the hands and arms leave the foramen in the neck vertebrae and exit via a ?gap? in the scalene muscles at the side of the neck. This very important gap is called the THORACIC OUTLET. A number of important blood vessels also leave this gap.
When your head is where it should be ( in other words balanced via the neck vertebrae and disks ), the muscles at the front, back and sides of the neck should be fairly relaxed, having minimal internal pressure. As soon as we start to get forward head posture ( from sitting improperly at computers, from having a ?head down? posture working on a machine, from a soldier carrying a heavy pack ), all that changes. Now, large amounts of pressure are put on the scalene muscles, and that THORACIC OUTLET gap starts to get smaller. Eventually, a point will be reached where the nerves and blood vessels get impacted. All sorts of problems can then occur ( and I say this from personal experience, as well as having seen hundreds of people with this condition at the clinics I go to ). Sharp shooting pains up and down the arms can occur, tingling in the fingers, pain in the fingers, pain and tingling in the neck, pain and tingling in the shoulders etc.
This is one of the most potentially serious conditions that can occur due to forward head posture, and is not to be taken lightly. Compression of the blood vessels reduces nutrition flow to the muscles and impairs waste removal.
Never cradle a telephone at the side of your neck.
I have seen half a dozen people ending up getting unecessary neck surgery due to the fact that the doctors who treated them, thought that the impingement was at the foraminal holes. It was not. It was at the thoracic oulet.
Note the median nerve in the previous diagram. As mentioned in the post about carpal tunnel, the median nerve is an important component. Entrapment of the nerve at the thoracic outlet can refer problems all the way down to the wrist ( weakness of grip, tingling etc ).
When we are kids, our muscles recover much quicker than when we are adults. People who have a ?head down posture? at video games, computers etc go to sleep at night, and the muscles initially relax and go back to their original size. If the head down posture continues regularly, adhesions and knots will gradually occur. Eventually the muscles will no longer return to their original state and the head will remain forward.