Hospitals in Indiana and Alabama have agreed to pay the federal government $8.3 million to settle a whistleblower lawsuit. The suit alleges the hospitals overcharged Medicare for routine back surgery, called “kyphoplasty.”

The six hospitals, three in Indiana and three in Alabama, settled the qui tam lawsuit ,which said that during a period from 2000 to 2008, hospitals kept patients overnight when it was not necessary, classifying the surgery as inpatient to boost hospital revenues.

This is the second group of hospitals to settle charges stemming from whistleblower lawsuits alleging Medicare billing fraud involving kyphoplasty.