My son aged 12 suffers from severs disease. It is now so bad that he has missed lots of school,only been at school 3days this academic year, and can only crawl or walk on tip toe. He has gel insole cups,has been taking Oscon and leg night splints plus painkillers at night. He also has weekly Bowen Therapy which eases the pain. Can you suggest anything else that we could do? how long is this likely to last?