Osteopathic fellowships require completion of an AOA-accredited residency. So, no, your scenario would not work. However, if you completed an AOA residency, you could enter an ACGME fellowship, then petition the AOA for accreditation of the post-graduate training. Or, you could enter an AOA fellowship after an AOA residency and not worry about it. Finally, you could complete an ACGME residency and fellowship, then petition for accreditation of both residency and fellowship. Too many choices, huh?