TUESDAY, March 19 (HealthDay News) -- Although most people get a total hip or knee replacement to decrease pain and move around more easily, a team of orthopedic surgeons has discovered an unexpected benefit: people enjoy sex more after surgery.

A new study found that total hip or total knee replacement surgery improved self-reported sexual function in 90 percent of patients.

Study author Dr. Jose Rodriguez, director of the Center for Joint Preservation and Reconstruction at Lenox Hill Hospital in New York City, created a survey to learn more about how sexual experience was affected by getting a new joint. He said he thought that if he brought up the topic by asking questions about sexuality, people would respond. And they did. "Most patients won't bring up the topic on their own," he said.

Rodriguez said that many patients fear they'll damage the new joint if they have sex, but don't ask any questions about it. Now he makes a point of telling people, after their operations, that "most of what you want to do -- physical and intimate -- you can do."

Getting total hip or knee replacement may improve overall well-being and self-esteem, which itself can be a turn-on, said Rodriguez. "Anything that causes pain and affects how you move is going to influence sexuality," he explained. After surgery, if you feel you are more sensual yourself, you're going to enjoy having sex, he added.

The study, which is scheduled to be presented Tuesday at the American Academy of Orthopaedic Surgeons annual meeting in Chicago, involved reports about sexual activity done before and after total hip or knee replacement surgery. Male and female patients under 70 years old were recruited from the practices of two arthroplasty surgeons. They were asked to anonymously complete and mail back one survey before surgery and two other surveys at six months and one year after surgery.

Out of 147 people who returned the preoperative questionnaire, 116 returned the six-month survey and 65 also sent back the one-year survey. The mean age of patients was about 58 years; there were 69 males and 78 females in the initial group.

Before surgery, 67 percent of respondents reported having physical problems with sexual activity that included pain and stiffness; reduced sex drive (49 percent); an inability to attain the necessary position (14 percent); and psychological issues such as a lack of well-being (91 percent) and low self-image (53 percent).

After surgery, 42 percent of the patients reported an improvement in interest in sex; 35 percent said they had increased duration of intercourse; 41 percent reported more frequent sex; 84 percent said they had improved well-being; and 55 percent reported having an improved self-image.

Hip replacement patients had a higher rate of improvement than did knee replacement patients, and after hip surgery, more females reported improvement in sexual activity than did males, the investigators found.

Rodriguez said the researchers think the results show that sexual function needs to be included in the routine evaluation of patients after both surgeries to help answer patients' questions about the safety of sex after surgery.

He noted a few limitations of the study: the results are based solely on the self-report by patients and includes only those responses sent back. "It's possible only the people interested in sex bothered to send back the surveys," he noted. Rodriguez also said he wished he had consulted with an expert in sexuality. "We basically just made up the questions we thought we should ask, with some help from some of our patients," he explained.

Yet the outcomes of the study make sense, said Dr. Giles Scuderi, vice president of orthopedics at North Shore-LIJ Healthcare System in Great Neck, N.Y. "The most important message here is overall performance and self-image are improved. Patients' lifestyles are definitely better after these surgeries," Scuderi said.

A second study slated to be presented at the meeting by Swiss researchers showed that patients undergoing total hip replacement surgery are more active than were patients who got the procedure a decade ago. They also found that most of them return to their previous recreational activities, including biking, hiking, swimming and golfing.

Scuderi said there are about 720,000 total knee replacement surgeries and 450,000 total hip replacement surgeries in the United States annually. On average, he estimated the cost for the surgery, hospital stay and implants for an average joint replacement is about $25,000, not including the cost of rehabilitation.

Because the studies were presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

More information

Learn more about joint replacement surgery from the U.S. National Institute of Arthritis and Musculoskeleta...nd Skin Diseases.