Probably any form of yoga would be helpful to those suffering from arthritis. Just be sure not to work through the pain--gentle stretches are best for beginners. Water aerobics will also increase muscle strength and flexibility. It might be best to start by using yoga as a form of relaxation and meditation. Water therapy, which is done in a swimming pool, is also helpful because the body is more buoyant and flexible making the exercises a bit easier for the patient.
Yoga done in a classroom setting has been been beneficial for those suffering from arthritis. When deep relaxation is combined with social contact, yoga can often reduce or eliminate depression and anxiety in the patient. Additionally, yoga is valuable because it treats pain, swelling, joint stiffness and lack of flexibility. Yoga is a "go-at-your-own pace" form of exercise and stretching. It is mild enough for even the greatest of arthritis pain.