"You might not want to rush into knee surgery. Physical therapy can be just as good for a common injury and at far less cost and risk the most rigorous study to compare these treatments concludes.    Therapy didnt always help and some people wound up having surgery for the problem called a torn meniscus. But those who stuck with therapy had improved as much six months and one year later as those who had arthroscopic surgery right away researchers found.    Both are very good choices. It would be quite reasonable to try physical therapy first because the chances are quite good that youll do quite well said one study leader Dr. Jeffrey Katz a joint specialist at Brigham and Womens Hospital and Harvard Medical School.    He was to discuss the study Tuesday at an American Academy of Orthopaedic Surgeons conference in Chicago. Results were published online by the New England Journal of Medicine.    A meniscus is one of the crescentshaped cartilage discs that cushion the knee. About onethird of people over  have a tear in one and arthritis makes this more likely. Usually the tear doesnt cause symptoms but it can be painful.    When that happens its tough to tell if the pain is from the tear or the arthritis  or whether surgery is needed or will help. Knee surgery for a torn meniscus is done about half a million times each year in the U.S.    The new federally funded study compared surgery with a less drastic option. Researchers at seven major universities and orthopedic surgery centers around the U.S. assigned  people with arthritis and meniscus tears to get either surgery or physical therapy. The therapy was nine sessions on average plus exercises to do at home which experts say is key to success.    After six months both groups had similar rates of functional improvement. Pain scores also were similar.    Thirty percent of patients assigned to physical therapy wound up having surgery before the six months was up often because they felt therapy wasnt helping them. Yet they ended up the same as those who got surgery right away as well as the rest of the physical therapy group who stuck with it and averted an operation.    There are patients who would like to get better in a fix me approach and surgery may be best for them said Elena Losina another study leader from Brigham and Womens Hospital.    However an Australian preventive medicine expert contends that the studys results should change practice. Therapy is a reasonable first strategy with surgery reserved for the minority who dont have improvement Rachelle Buchbinder of Monash University in Melbourne wrote in a commentary in the medical journal.    As it is now millions of people are being exposed to potential risks associated with a treatment that may or may not offer specific benefit and the costs are substantial she wrote.    Surgery costs about  compared with  to  for a typical course of physical therapy Katz said.    One study participant  Bob OKeefe  of suburban Boston  was glad to avoid surgery for his meniscus injury three years ago.    I felt better within two weeks on physical therapy he said. My knee is virtually normal today. He still does the recommended exercises several times a week.    Robert Dvorkin had both treatments for injuries on each knee several years apart. Dvorkin  director of operations at the Coalition for the Homeless in New York City had surgery followed by physical therapy for a tear in his right knee and said it was months before he felt no pain.    Then several years ago he hurt his left knee while exercising. I had been doing some stretching and doing some pushups and I just felt it go pop. he recalls. I was limping. It was extremely painful.    An imaging test showed a less severe tear and a different surgeon recommended physical therapy. Dvorkin said it worked like a charm  he avoided surgery and recovered faster than from his first injury. The treatment involved two to three hourlong sessions a week including strengthening exercises balancing and massage. He said the sessions werent that painful and his knee felt better after each one.    Within a month I was healed Dvorkin said. I was completely back to normal."