ISHA MEETING SAN FRANCISCO 2016 What I have learned in over a decade about acetabuloplasty and pincer impingement

 Two distinct types of FAI: Cam and rim or pincer impingement.  Pincer impingement is believed to result from abnormal extensión/contact (Bony prominence) of the anterior and/or posterior walls or acetabular roof relative to the center of the femoral head, causing an abutment of the acetabular rim against the femoral head-neck junction.  The term pincer impingement was defined in 2003 by Ganz (1).  This type of impingement can occur as a result of several distinct structural abnormalities.  Pincer impingement harder to diagnose that Cam.  Significant controversy surrounding the diagnosis and treatment of this disorder and its associated conditions.  In clinical practice, isolated pincer impingement is rare. In one epidemiologic study (Beck et al) of 149 hips with impingement, 26 (17.4%) had isolated cam impingement, 16 (10.7%) had isolated pincer impingement, and 107 (71.8%) had combined cam-pincer impingement .