For consumers who read these titles we like to clarify terminology and also to understand that chairs in and of themselves do not prevent MSI’s (misnamed RSI’s here). RSI stands for repetitive strain injury. In Canada we more correctly call this Musculoskeletal Injuries which arise from a combination of ergonomic hazards being present. Assuming these MSI’s arise from repetition is incorrect and has no relationship to the science of ergonomics. Repetition is one of 7 ergonomic hazards which need to be quantified by a certified ergonomist before making a conclusion about causaility. It is only after this method has been applied that a number of recommendations can be made one of which may or may not be a chair. The recommendations should always include an Administrative Section which managers and supervisors need to pay attention to; and a Behavioural section which the employee is responsible for such as taking regular breaks away from the workstation. The chair no matter how well designed is NOT a panacea (we do not sell furniture or seating in our practice at OPC) and is only 1 of many tools to be used at the right time and for the right reasons. You can now see hopefully that Ergonomics is indeed a science and one that should be performed by qualified and certified professionals. JE Sleeth Reg PT, ACE