I like the simplicity of your drawing, and nice colours you have chosen, which look better than the black and white. Perhaps the head might be a colour instead of black? Perhaps there are other simple yoga-like poses to create? Check out our website, which is about to be updated, for some image ideas we have been playing with: http://www.newbacktherapy.com/TheNewBackProgram.html
One of my colleagues really likes this: "Clean lines, simple, professional look. I like the flowing symmetry and color combinations. The body is symbolized in a simple form."
My partners will look further later today, and respond to you with more suggestions..
Your font choice has a nice professional appearance. The pictorial element could be played with some more. It is elegantly simple, although some feedback I have received suggests it may be too simple, and lacks something... perhaps a background? Or perhaps a border on one side? Something to suggest a back...?
The color combination of the image in versions #4 and #5 were preferred. Also, creating versions with the word NewBack prominent on the first line and the word Therapy secondary on the second line (and in smaller font and in grey) were also preferred. Do not include the Inc in any versions.