What is hip impingement? What is femoroacetabular impingement (FAI)?
Femoroacetabular impingement (FAI), also known as hip impingement, is a condition where the bones of the hip joint do not have a matching shape. During movement this mismatch leads to friction in the joint. Depending on the severity of the mismatch and the activities this may damage the cartilage and tissues surrounding the joint. The symptoms of FAI are pain of the hip and a reduced range of motion. When the cup gives too much coverage, leading to impingement, this is called Pincer type impingement. When the head of the femur has a bump that causes impingement, this is called a Cam type impingement.
Hip arthroscopy, a rising star
In many cases of hip impingement it is possible to perform 'joint preserving surgery'; the surgeon removes the excess bone and tries to maintain as much of your hip joint as possible. When the bone areas that caused impingement are removed, the joint can move freely again. Joint preserving surgery may allow you to return to practicing active sports again. An increasing number of surgeons perform this type of surgery arthroscopically: they use a camera and tools for which no incision is required. The advantage of an arthroscopic procedure compared to open surgery is that less damage is being done to the tissues surrounding the joint.
Traditional diagnosis for FAI, hip impingement
The sooner hip impingement is detected, the better. However, early stage FAI can be difficult to detect. Pain complaints may be caused by a variety of reasons, so radiological images are required to inspect the joint. Every surgeon will have a personal preference on the type of diagnostic images to use for diagnosis and assessment of hip impingement. Some choose MR (based on magnetism), some choose CT (based on x-rays), and some only use simple radiographs. Not every shape deviation in the hip joint will be a cause for hip impingement. Therefore, the challenge is to determine which shape deviations are causing hip impingement and should therefore be removed in a surgical procedure.