Almost every physician practicing today has been taught a structural model of pain. If we see something abnormal on an MRI of a part of that body where the patient is experiencing pain, we assume that the abnormality is causing the pain. If just as many abnormalities could be found in patients without pain as those with pain, this would call into question the whole structural model of pain.
How inaccurate is our structural model of pain? Although the model is amazingly compelling, research behind it holds as much water as a sieve. A case in point is meniscus tears. Billions of dollars have been spent on surgeries to treat patients reporting knee pain whose MRIs also exhibited meniscus tears. Studies show, however, that in middle aged and older patients, meniscus tears are like grey hair—they’re found in just about everybody whether they have knee pain or not. The MRI findings doctors rely on when looking at the spine also show just as many abnormalities in pain-free patients as in those patients with pain.
A study reported in the March 2015 American Journal of Sports Medicine shows similar findings in the world of rotator cuff surgery. Authors of the study looked at 140 patients undergoing surgery for one shoulder that hurt, and that showed a tear on imaging. They also looked at images of the opposite pain-free shoulder. More than one third of the patients who had rotator cuff tears on both shoulders curiously had pain in only one shoulder. A study reported in the November 2014 International Journal of Rheumatic Diseases also failed to find any differences in the shoulder MRI findings of patients with and without shoulder pain. Some rotator cuff tears hurt, and some do not.
An MRI of the shoulder can be very useful when combined with a detailed hands-on exam that looks at the shoulder and neck—and lasts more than a few minutes. We should beware, however, of basing surgical decisions on MRI results alone.
Do Shoulder Rotator Cuff Tears Hurt? first appeared as a post on the Regenexx Blog.