Over 40? Your rotator cuff probably looks a little rough

After age 40, we may all have busted-looking shoulders. But that doesn’t mean anything is wrong.

In a study of hundreds of people, MRI images showed that nearly every person scanned had frayed, torn or otherwise abnormal rotator cuff tendons, researchers report February 16 in JAMA Internal Medicine. Those abnormalities didn’t automatically signify problems or a need for surgery, though — they showed up in people with or without symptoms.

One take-home message is that MRIs aren’t so useful for diagnosing shoulder pain, says Brian Feeley, an orthopedic surgeon at the University of California, San Francisco who wasn’t involved with the work. Instead, the imaging test reveals a bigger picture about aging: When it comes to the structure of our skeletons and all the tendons and tissues that support it, he says, our bodies look different as we grow older. “And that’s not necessarily a bad thing.”

The rotator cuff is the group of muscles and tendons surrounding each shoulder joint. It helps control where your arm is in space, Feeley says. It’s also a common source of shoulder pain. Surgery can repair rotator cuff tears and the number of such operations has been trending upwards. From 2007 to 2016, the rate of these repairs in the United States rose more than 1 percent every year, researchers reported in 2021. This may be due, in part, to more patients getting MRIs, Feeley wrote in a commentary accompanying the new work. Hundreds of thousands of patients get the repair each year.

Previous studies have hinted that shoulder abnormalities visible via MRI aren’t always accompanied by symptoms. The new study offers definitive evidence that such abnormalities are a normal part of aging, Feeley says.

Researchers scanned the shoulders of Finnish adults ages 41 to 76 years and noted shoulder pain or other issues. While 110 out of the 602 participants experienced such symptoms, all but seven had a rotator cuff abnormality, like a partial or full tendon tear. That “means that the mere presence of an abnormality has limited diagnostic value,” writes study coauthor Thomas Ibounig, a shoulder and elbow surgeon at Helsinki University Hospital.

The new work isn’t saying shoulder MRIs are useless. When surgery is required, Feeley uses the technology to plan where he’ll anchor torn tendon to bone. But for diagnosis, he sticks to the basics, like listening to patients describe their symptoms, taking their history and doing a physical exam. “Old-school medicine,” Feeley says.