There is a small detail that you might like to add in to your forward thinking, which takes the notion of some form of certification for ‘good’ chair shapes a step further than we discussed yesterday.

What is to me so delightful is Dr Henry has very elegantly identified the core detail of ‘good sitting’ as maintaining the angle of the pelvis, so that the first few vertebrae above it are sustained in their right geometric relationships and carry their loads easily, without the geometry becoming distorted and the surrounding tissue strained, causing back problems. The notion of some form of certification process hinges around the understanding of the notion of ‘good sitting’.

There is a step beyond this. Once the notion of ‘good sitting’ becomes not only well understood but also well accepted – and I think we have enough clarity from all the work that Dr Henry has pulled together, and enough medical agreement about that work, for this to happen – there comes a point where it becomes professionally unacceptable to sell chairs that cause ‘bad sitting’ and will in due course cause back ache. At this point the position of the global chair industry shifts, because you cannot sell large numbers of office chairs that are known to induce back problems and open yourself up to what the Americans would call a class case in the law courts, accusing you of knowingly selling a harmful product.

I guess the example would be seat belts in cars. It is not only that they save lives for those in the car. They save an inordinate amount of accident and emergency time and effort in hospitals on Saturday nights. So we don’t wear seat belts ‘because they are a good thing’ we wear them because not to do so is a bad thing.

There are of course many, many ways of producing ‘good sitting’. But where I think there is real value in the simple clarity that Dr Henry has achieved in his work, is that the essentials of ‘good sitting’ are made very clear. And THAT – the spreading of that message – in the end has the power to ban ‘bad sitting’.            Best regards,     Jim

The present position.

Prevalence and economic cost of LBP.→   The actual increase of mechanical spinal pathology and backache prevalence seems to be a genuine phenomenon of the 20th century and is rising exponentially (Hemingway 1997) with the increase in sedentary occupations.

In the United States About 100 million workdays are lost annually  (Johanning 2000).  Insurance figures show that 82% of US office workers complain of LBP (personal communication 2012 HAS),   Lower back pain’s economic impact is shown to be the number one reason for individuals under the age of 45 to limit their activity, second highest complaint seen in physician’s offices, fifth most common requirement for hospitalization, and the third leading cause for surgery.  (Health and Safety Executive‘s Better Backs   .https://en.wikipedia.org/wiki/Health_and_Safety_Executive).

Mandal AC  showed that the recommended ‘correct’ position was fundamentally wrong.   This has been validated by subsequent research but is still advocated as ‘correct’.    He  suggested  that   “Mankind has progressed from Homo sapiens to Homo sedens”.                    (See  ☛ Why? Mandal’s Homo sedens.)

→  He advocated a forward tilted seat (FTS) which is incorporated into the  Ischial off-load system now used by some high-end office chairs.    (See  ☛ . mid-upright sitting.→).