It's the worst kept secret in all of medicine: Docs who own testing equipment order more tests.

The more expensive the equipment, the more tests they order.

Think about that next time your own doc breaks a bottle over a brand-new $2 million MRI machine that comes with $800,000 a year in operational expenses.

You know he's going to recoup that money--and he's probably going to do it on the backs of one set of patients in particular: people fighting back pain.

Now, researchers confirm that docs who get MRI machines order more scans for patients with low back pain and perform more surgeries--despite the fact that there's usually no real medical reason for the scans or the surgeries.

Researchers from the Stanford University School of Medicine examined a sample of 20 percent of all Medicare claims for low back pain submitted by primary care doctors and orthopedists between 1998 and 2005.

Then, they compared the rates of MRI referrals of 1,271 orthopedists and 1,033 primary care doctors before and after they purchased or leased the machines.

They found that the number of MRI referrals shot up by 32 percent in primary care docs after they got their own machines... and by 13 percent in orthopedists, according to the study in Health Services Research.

And that's not even the worst part of this.

There was actually a 34 percent increase in surgeries among orthopedic patients in the six months after those docs got their own MRI machines--despite the fact that surgery for low back pain was, and remains, a crapshoot no matter what kind of imaging your doctor uses.

And that's because, over time, all our bodies develop little quirks and issues that don't quite look right on a scan... but don't really cause us pain, either.

For example, one study of seniors found bulging discs or spinal disc degeneration in 90 percent of them. But here's the thing: None of these seniors actually had any back pain.

And that means the real cause of back pain for most people is something that won't turn up on any MRI, CT scan or X-ray.

For most, the pain goes away on its own within a few months.

For others, the pain is caused by a lifestyle-related issue--anything from poor exercise habits to poor posture... or even an undiagnosed injury that can be treated with rehab instead of surgery.

Instead of expensive imaging tests and surgical procedures that rarely provide long-term relief, find the real cause of your pain--and fix it before you find yourself paying for some orthopedist's shiny new toy.