The HHS Office of Inspector General (OIG) reports that in 2006, Medicare inappropriately paid a total net $178 million (out of $466 million) for chiropractic services that reviewers determined to be maintenance therapy, miscoded, or undocumented. The OIG recommends that CMS take a number of steps to address continuing vulnerabilities in this area, including implementing a new modifier for chiropractic claims to indicate the start of a new episode and/or a cap on allowed chiropractic claims. CMS also should ensure that chiropractic claims are not paid unless documentation requirements are met.