Knee Osteoarthritis: A 2006 study published in the Journal of the American Medical Association concluded that massage therapy seemed to be efficacious in treating osteoarthritis of the knee. A 2012 study published in Plos One (Public Library of Science) determined that a weekly 60-minute massage is optimal for treatment of osteoarthritis of the knee.
Lower back pain: Findings of a 2012 controlled trial published in the Annals of Internal Medicine by Dr. Daniel C. Cherkin at the Group Health Research Institute in Seattle stated, "Massage therapy improved function and decreased pain more than usual care in patients with uncomplicated chronic lower back pain after 10 weeks."
Headaches:
Tension Headaches: A 2002 study in the American Journal of Public Health showed that massage therapy significantly reduced headache frequency and duration of chronic nonmigraine headaches.
Migraines: And in a 2006 study, published in the Annals of Behavioral Medicine, participants who had massages had fewer migraines and slept better during the weeks they had massages.
Cancer Pain: A meta analysis of 12 studies published in ResearchGate in 2015 concluded that massage has "a beneficial effect for relief of cancer pain."