Newswise — The knees suffer injury more often than any other joint, in part because of their intricate system of ligaments. Women are especially prone to knee problems, and they injure the anterior cruciate ligament (ACL) twice as often as men. Knees & Hips: A Troubleshooting Guide to Knee and Hip Pain, a new report from Harvard Medical School, explains how a combination of anatomy and hormones contribute to women's weak knees. The report also outlines steps women can take to reduce their risk of knee injury.

According to Knees & Hips, the Q-angle, the angle formed at the knee where the slanting line of the femur (thigh) bone meets the vertical line from the kneecap to the ankles, is more pronounced in women than in men because women tend to have wider hips. This increases strain on the knee. Researchers also speculate that high levels of estrogen can make the knee ligaments more flexible while weakening their shock absorption.

Differences in training techniques may add to the problem. For example, female athletes, who run in a more upright position than men, tend to strongly contract their quadriceps, which also increases stress on their ligaments.

The report explains how to safely reduce the risk of knee injuries by wearing the right shoes, stretching the quads and hamstrings before exercise, and being mindful during exercise. It also discusses symptoms and treatment for specific knee injuries.

Knees & Hips is edited by David Scott Martin, M.D., Ph.D., Assistant Professor of Orthopedic Surgery at Harvard Medical School and Attending Orthopedic Surgeon at Brigham and Women's Hospital. Additional topics in the 41-page report include:"¢ innovative testing for knee and hip problems"¢ nonsurgical treatments for knees and hips"¢ joint replacement, including what it's like to undergo surgery and how to rehabilitate at home.Knees & Hips: A Troubleshooting Guide to Knee and Hip Pain is available for $24 from Harvard Health Publications, the publishing division of Harvard Medical School. Order it online at www.health.harvard.edu/KH or by calling 1-877"649"9457 (toll free).