Effect of cam-type deformity associated with femoroacetabular impingement on hip mechanics

Hip osteoarthritis (OA) is a painful condition affecting 4.4 per cent of the population aged 55 and older. Currently, there are very limited treatment options and no known cure for OA. Improving prevention and treatment of early hip OA requires a thorough understanding of the joint mechanics and how these mechanics affect the initiation and progression of the disease. Hip OA can either be primary (occurs with no previously known cause) or it can be secondary to a known deformity. It has recently been hypothesized that most “”primary”” cases are actually caused by small deformities in the joint that were previously unnoticed. One deformity that has been found to have a strong correlation with hip OA is called a cam deformity, which can cause pain and decreased range of motion in the hip. Cam deformities occur on the upper femur (thigh bone) and cause increased contact between the femur and the acetabulum (hip socket). Joint contact pressure is thought to play a role in accelerating the onset of OA. To determine the association between cam deformity and the onset of hip OA, Laura Given is studying how the joint mechanics change depending on the degree of cam deformity. She will track how the joint translations and rotations are affected throughout the range of motion of the hip and determine how the range of motion is affected by simulated cam deformity. By describing how the size of cam deformity affects joint mechanics, Given’s research will help surgeons understand how to effectively correct the deformity in an effort to slow or even stop the osteoarthritic disease progression. It could also lead to preliminary guidelines in arthritis screening programs. This could reduce the number of cases of hip OA seen in the future.