rheumatoid arthritis is not an easy condition to treat. It doesn't have a cure. Medical management can only go so far. There are rheumatologist out there so hopefully they have a specialist working with them. Traditionally the best place for Rheumatology in NZ is rotorua because of the local hot springs. Hense I would suggest hydrotherapy in heated pools looking to do strengthening. Using electromodalities such as laser is ok - not my treatment of choice - but as it isn't working they need to be doing something more active. Strengthening for the knee is important with arthritis and the least painful situation would be to do it in a heated pool. Get them to find a physiotherapist who can provide that.