What Happens When You Sit

 A “Bare Bones” explanation of why we can get pressure sores and pain from sitting too long. When we see another person, we don’t see the bone structure that is the framework that  we are built on. This skeletal frame is marvelously designed and built to allow us to do most anything we might be able to want to do. We are not well designed to sit for long periods without moving. In fact, we are not designed to “not move” for periods of time longer than 20 minutes according to several respected plastic surgeons I have discussed this question with. We are designed to keep moving, even in our sleep so that when any part of the soft tissue that covers our skeletal frame is squeezed between the bone and the support surface, something in our subconscious causes us to move and change position to lower the pressure on the soft tissue so we move, whether sitting in a chair or even while sleeping. When we sit, the soft tissue between the ischial bones and the support surface outside gets compressed with so much pressure that the tissue and skin gets all the blood squeezed out of it.


See illustration #1
We have placed our employee, Mr. Bones in a chair sitting with an ischial on a scrap of foam urethane. As you can see, the pressure of the ischial bone is compressing the foam into a virtual solid under pressure.
The foam represents the soft tissue and skin over the bone when you sit, this happens inside your body! Something in our subconscious prompts us to move when an area such as this has been deprived of blood, so that the fresh blood comes back in and supplies the nutrients to keep the tissue healthy. For someone who is incapable of moving because of injury or disease, this can cause a lot of pain (if they can feel pain) or for many people with spinal cord injuries (SCI) they don’t feel pain or discomfort so are at far greater risk of pressure sores. If they have no feeling it is absolutely mandatory that they be moved by another person, or perhaps tilting their wheelchair, anything to relieve that pressure to allow fresh blood to flow. If fresh blood is not there for more than 20 minutes, some small percentage of the cells start to die from lack of fresh blood and if the time extends to 2 hours or so, a bad pressure sore is virtually the guaranteed result. The ischial bones that we all sit on can also be almost sharp edged in some people which make them even more susceptible to soft tissue damage from not moving. What we are talking about here is the real cause of “pressure ulcers” as they are often called. While pressure is part of the cause, the real culprit is lack of movement! All the seating systems built by Best Seat and the parent company Ease Seating Systems, use Computer Controlled Pressure Management (C.C.P.M.) which I invented and patented in 2000.


When we sit we have a lot of pressure on the ischial tuberosities, the two bony projections on the bottom side of the pelvic bone structure. About 65% of our weight is upper body weight which is transferred to the spinal column and into the pelvic structure. All this weight is pushing the ischials into the soft tissue from the inside and the support surface you are sitting on is pushing back with enough force to support your weight.


The soft tissue between the bone and the support surface is being compressed and the blood is being squeezed out of it! You must move in a timely manner, at least once every 20 minutes or some of the cells in the soft tissue will die from lack of fresh blood. The longer you sit without moving, the more likely you will have enough cellular damage to have a pressure sore. Unrelieved pressure without movement equals a pressure sore.We combat this problem with artificially created movement which causes the tissues to get a good exchange of fresh blood. Nature does the rest. Movement equals good soft tissue health. Our seating products provide movement!




The purpose of this portable alternating pressure cushion concept is to provide artificial movement, controlled by a computer chip, operating a battery driven air pumping system that provides the all important movement. Most of our customers are dealing with some degree of mobility impairment, but our systems can and do compensate for their inability to move by using artificial means to replace the movement they have lost.


Our systems are a Godsend to severely disabled people and also a blessing to the care givers who previously had to be super vigilant about lifting and turning at least every 1/2 hour to prevent tissue breakdown. Now, as they sit on our moving alternating pressure cushioning system; they do not have to be assisted to have soft tissue prevention that works. Movement is the only thing that will prevent soft tissue breakdown. Any cushion that does not move simply is not up to the task of prevention. But don’t take my word for it, read the full report of United States Air Force Research Laboratory. Click here for the full report. Also read the testimonials of our customers. Their lives have been changed for the better by our systems. Compare the life you live with the quality of our customer’s lives on our Computer Controlled Pressure Management systems. If you want to live as they do, get the seating systems they have found to work for them.


Skin breakdown and chronic pressure sores are totally preventable in most people. Quit spending time and money treating pressure sores and prevent them. Life in a wheelchair probably wouldn’t have been your first choice, but it can be so much better and productive if you don’t have skin breakdown problems, to solve that problem, please talk to us. Our only business is helping people in wheelchairs get the most out of life! We have the seating systems and alternating pressure mattress products, plus 14 years of experience in keeping people happy and healthy in their chairs and their lives. You don’t have to have pressure sores just because you are in a wheelchair. Our customers are living proof of that! Let us help you with your wheelchair seating. You’ll be glad you did.

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