Mayo Clinic researchers reported that one in five cases experienced fracture of a bone within an average of seven years after the surgery. Major fractures occurred in hands and feet but hip, spine and humerus (upper arm bone) fractures also were found.

We knew there was a dramatic and extensive bone turnover and loss of bone density after bariatric surgery, said study senior author Dr. Jackie Clowes, a Mayo rheumatologist. But we didn’t know what that meant in terms of fractures.

The ongoing study involves a review of the records of 292 people who had bariatric procedures like stapling of the stomach (gastric bypass) or banding of the stomach (gastric band surgery), over two decades at the Minnesota facility. The procedures are done to minimize the intake of food and nutrients into the body.

The results from 97 surgical patients were to be presented at the Endocrinology Society’s annual meeting in Washington, D.C.

The study found that in the group, 21 people had 31 fractures. According to background information that’s a fracture rate nearly twice what would be expected in a comparable group of people who’d not had the surgery.

Researchers reported that further study is needed to determine what causes the increased risk for fractures.