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Review
. 2019 Sep;12(3):253-259.
doi: 10.1007/s12178-019-09559-1. Epub 2019 Jul 5.

Etiology and Pathomechanics of Femoroacetabular Impingement

W Jeffrey Grantham  1 , Marc J Philippon  2   3
Affiliations
Review

Etiology and Pathomechanics of Femoroacetabular Impingement

W Jeffrey Grantham et al. Curr Rev Musculoskelet Med. 2019 Sep.

Abstract

Purpose of review: Femoroacetabular impingement is a common cause of hip pain in young patients and has been shown to progress to osteoarthritis. The purpose of this review is to better understand the development of femoroacetabular impingement.

Recent findings: Recent literature shows little genetic transmission of FAI. However, molecular studies show strong similarities with the cartilage in osteoarthritis. The development of cam lesions has a strong association with sports participation, particularly at the time of physeal closure suggesting abnormal development. Lumbar, pelvis, and femoral biomechanics may also play an important role in dynamic impingement. In summary, femoroacetabular impingement is a dynamic process with many influences. Further research is needed to clarify the pathophysiology of FAI development in hopes of finding preventative options to reduce symptoms and progression to osteoarthritis.

Keywords: Cam development; FAI etiology; FAI pathomechanics; FAI pathophysiology; Femoroacetabular impingement; Pincer development.

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Conflict of interest statement

W. Jeffrey Grantham declares that he has no conflict of interest. Marc J. Philippon reports royalties from Smith & Nephew, Arthrosurface, Arthrex, Bledsoe, ConMed Linvatec, DonJoy, SLACK Inc., and Elsevier, consultancy fees from Smith & Nephew and MIS, and research support from Smith & Nephew, Ossur, Arthrex, and Siemens.

Figures

Fig. 1
Fig. 1
Cam lesions, identified by the arrows on the AP and frog leg lateral radiographs, are osteochondral extensions along the femoral head-neck junction
Fig. 2
Fig. 2
Pincer lesions, identified by the arrows on the AP pelvis radiograph, are over coverage of the acetabulum
Fig. 3
Fig. 3
Measuring the alpha angle at 76.9° to evaluate for a cam lesion
Fig. 4
Fig. 4
Measuring the lateral center edge angle at 32.9° to evaluate for a pincer lesion
Fig. 5
Fig. 5
AP and frog leg lateral radiographs of a patient’s right hip showing an anterior cam lesion with alpha angles of 44.5° on the AP and 64.4° on the lateral
Fig. 6
Fig. 6
Sagittal and coronal T2 MRI images identifying the chondrolabral injury due to femoroacetabular impingement
See this image and copyright information in PMC

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