Med Library . org

Open Source Encyclopedia

Femoral Acetabular Impingement

Welcome to MedLibrary.org. For best results, we recommend beginning with the navigation links at the top of the page, which can guide you through our collection of over 14,000 medication labels and package inserts. For additional information on other topics which are not covered by our database of medications, just enter your topic in the search box below:

Femoroacetabular Impingement (FAI) or hip impingement syndrome is a condition affecting the hip joint in young and middle-aged adults.[1] Impingement occurs when the ball shaped femoral head rubs abnormally[2] or does not have full range of motion in the acetabular socket.[3] Damage in the hip joint can occur to the articular cartilage or the labral cartilage (soft tissue bumper of the socket). Treatment options vary from conservative treatment to arthroscopic and open surgery.

Contents

Overview

The three recognized types of femoroacetabular impingement.

FAI is regarded as a cause of premature hip osteoarthritis.[4] The condition is characterized by abnormal contact between the proximal femur and rim of the acetabulum (hip socket). In most cases, patients present with a deformity in the femoral head or acetabulum, a poorly positioned femoral-acetabular junction, or may present with both. It is believed that a combination of certain factors may lead to some form of FAI. Predominantly, a marginal developmental hip abnormality together with environmental factors such as the partaking in activities involving recurrent motion of the legs within a supraphysiologic range.[5]

Three types of FAI are recognized. The first involves an excess of bone along the upper surface of the femoral head: this is known as a Cam deformity, the name is short for camshaft as the form of the femoral head and neck resembles a camshaft. The second is due to an excess of growth of the upper lip of the acetabular cup and is known as the Pincer deformity. The third is a mixture of the preceding two forms. The result of any of these deformities is increased friction between the acetabular cup and femoral head which may result in pain and loss or reduction of hip function.

Individuals with FAI tend to have an active lifestyle prior to diagnosis.[4] However, FAI-related pain may occur within a normal range of motion during actions not normally associated with a need for physical demand such as the motions of sitting down and standing up.

Diagnosis

FAI-related pain is often felt in the groin, but may also be experienced in the lower back or around the hip.[4] The diagnosis of FAI typically involves a physical examination in which the range of motion of the leg in relation to the hip is tested. Positive limited flexibility would lead to further examination with x-ray, for a two-dimensional view of the hip joints. Subsequent imaging techniques such as a CT or MRI scan may then be used in order to produce a three-dimensional image showing the condition of hip cartilage, signs of osteoarthritis, or angles of the hip socket (e.g. the alpha-angle as described by Nötzli[6] in 2-D and Siebenrock in 3-D[7]). It is possible to perform a dynamic simulation of hip motion using CT or MRI data.[8][9] Dynamic simulations may be useful to establish whether, where and to what extent hip impingement is occurring in a hip joint.

Treatment

The treatments for FAI vary considerably. Conservative treatments for FAI may include reducing levels of physical activity and having pain medication and physiotherapy sessions. Physical Therapy [physiotherapy] intervention may help to optimize alignment and mobility of the hip joint, therefore, decreasing excessive forces on irritable or weakened tissues. Physical Therapy can also help to identify specific movement patterns that may be injuring the involved hip.

Due to the condition being diagnosed frequently in adolescents and young adults, various surgical techniques have been developed in order to preserve the hip joint. Surgery may be arthroscopic or open.[4] Periacetabular or rotational osteotomies are two common open surgery techniques that may be performed if investigations have shown there to be an abnormal angle of the hip joint. These primarily aim to alter the angle of the hip socket in such a way that contact between the acetabulum and femoral head are greatly reduced, allowing a greater range of movement. Femoral sculpting may be performed simultaneously, if required for a better overall shape of the hip joint. It is unclear whether or not these interventions effectively delay or prevent the onset of arthritis. Well designed, long term studies evaluating the efficacy of these treatments have not been done.

Notable persons who suffered hip impingements

References

  1. ^ Dooley PJ (January 2008). "Femoroacetabular impingement syndrome: Nonarthritic hip pain in young adults". Can Fam Physician 54 (1): 42–7. PMC 2293316. PMID 18208954.
  2. ^ "Femoroacetabular Impingement (FAI)". Hipfai.com. Retrieved March 18, 2013.
  3. ^ [1]
  4. ^ a b c d Chakraverty, JK; Snelling, NJ (2012). "Anterior hip pain-Have you considered femoroacetabular impingement?". International Journal of Osteopathic Medicine 15 (1): 22–27. doi:10.1016/j.ijosm.2011.09.003.
  5. ^ Michael Leunig, Paul E. Beaulee, Reinhold Ganz. "The Concept of Femoroacetabular Impingement, Current Status and Future Perspectives", Clin. orthop., 2008, 467(3).
  6. ^ Nötzli HP, Wyss TF, Stoecklin CH, Schmid MR, Treiber K, Hodler J., "The contour of the femoral head–neck junction as a predictor for the risk of anterior impingement", J Bone Joint Surg Br, 2002, 84:556 –560
  7. ^ Siebenrock KA, Ferner F, Noble PC, Santore RF, Werlen S, Mamisch TC, "The Cam-type Deformity of the Proximal Femur Arises in Childhood in Response to Vigorous Sporting Activity", CORR, 2011, 469, 11, p3229-3240
  8. ^ Tannast, Moritz. "Noninvasive three-dimensional assessment of femoroacetabular impingement", J Orthop Res, Jan 2007. 25(1):122-31.
  9. ^ http://www.clinicalgraphics.com Dynamic motion simulation for hip impingement.