FAI and CAM Impingement found in Normal Pain-free Hips!

CAM impingement?  This past year or two has been what I call hip labrum “mania”. It’s all the rage in orthopedic surgical circles. I have blogged before on how this hip problem is over diagnosed. The usual picture looks something like this, the patient has hip pain and a hip MRI (usually with contrast) is performed, which then leads to the diagnosis of a small tear in the labrum and CAM impingement (aka FAI or femoral acetabular impingement) being identified. This then leads to highly invasive surgery where the hip labral tear is sewn up and the outside of the hip socket is completely surgically remodeled to “alleviate” the hip impingement. The surgery is so invasive, that in order to get enough room for the arthroscope, massive amounts of hip traction have to be used, which pulls so hard on the main nerves of the thigh that these nerves loose their ability to conduct impulses and have to be monitored electrically to prevent permanent nerve damage. All of this may make some sense if there was copious evidence that CAM impingement is only found in patients with hip pain and arthritis, it all makes much less sense if CAM impingement is reasonably common in normal patients without hip pain. Enter a new study that shows that almost 30% of hips in normal healthy males without pain met one or more diagnostic criteria for CAM impingement! This “abnormal” appearance on MRI was twice as common in men as women. The upshot? Like a bevy of findings seen on MRI of the low back and knee, just because something is seen on MRI doesn’t mean it’s causing pain or other issues and needs aggressive surgical management. If you’ve been diagnosed with hip impingement, especially if you’re male, make sure you’re not in the 1/3 of patients for whom this is just likely a variation of normal anatomy.