A Medicare Advantage/HMO plan is a “gatekeeper” system. All of the beneficiary/member’s doctors have to be in the same medical group and take the Medicare Advantage HMO plan that best fits your wife’s medical and prescription drug needs. Should one of her doctors either not be a part of the same medical group as the rest of her doctors and/or does not accept Medicare Advantage plans, then when your wife sees this physician she becomes a private pay (solely financially responsible) for services received from this out of network physician.
Another option is for her to look at a Medicare supplement/medigap policy which, for a monthly premium, will typically allow her to go to the Medicare physician of her choice. Medicare supplements/medigap policies are defined by Medicare and offered by insurance companies. However, in addition to the supplement/medigap policy, your wife would also have to sign up for a stand-alone prescription drug plan.