Medicare coverage for chiropractic services extends only to treatment by means of manual manipulation of the spine to correct a subluxation, provided such treatment is reasonable and medically necessary and legal in the state where performed. All other services (i.e., x-rays, ultrasound, and massage) furnished or ordered by chiropractors are never payable by Medicare and are therefore referred to as “noncovered services.” Services provided to beneficiaries which are billed with CPT codes 98940 (CMT: spinal 1‑2 regions), 98941 (spinal 3‑4 regions), and 98942 (spinal 5 regions) may be paid for under the Medicare Program depending on medical necessity and are therefore referred to as “covered services.”
Under the Medicare Program, chiropractic maintenance therapy is not considered to be medically reasonable or necessary, and is therefore not payable. Maintenance therapy is defined as a treatment plan that seeks to prevent disease, promote health, and prolong and enhance the quality of life; or therapy that is performed to maintain or prevent deterioration of a chronic condition. When further clinical improvement cannot reasonably be expected from continuous ongoing care and the chiropractic treatment becomes supportive rather than corrective in nature, the treatment is then considered maintenance therapy. For additional information regarding maintenance therapy, refer to the Centers for Medicare & Medicaid Services (CMS) Internet-Only Manual (IOM) Publication 100-02, Medicare Benefit Policy Manual, Chapter 15, Section 30.5. (1 MB)
A beneficiary should be given an ABN, when a provider is performing maintenance therapy. As of 6/21/2017, the revised ABN (Form CMS-R-131 with the expiration date of 3/2020 printed in the lower left hand corner) is the only ABN form to be used. If an older version of an ABN (form CMS-R-131 release date 03/2011 printed in the lower left hand corner) is used after 6/21/2017, the ABN is considered invalid and the provider will be held liable for the services rendered.
The ABN gives the beneficiary three options for billing, or not billing, these services to Medicare.
Modifier AT (active treatment) must be appended to the chiropractic manipulation code to indicate the manipulation was for medically necessary and reasonable treatment of an acute subluxation or chronic subluxation as defined in national policy and LCD L33613. LCDs are located on our website under Medical Policy & Review > Medical Policy Center. The AT modifier should not be placed on the claim when maintenance therapy has been provided. Claims without the AT modifier will be considered as maintenance therapy and denied.
Modifier GA is used when the provider has issued a valid ABN for maintenance care and the beneficiary has selected Option 1. This modifier may also be used on assigned claims when a patient refuses to sign the ABN and the latter is properly witnessed. When using the modifier GA, it must be appended to the spinal manipulation CPT code. If no modifier is appended to the spinal manipulation codes the claim will deny in the system as not medically necessary.
Modifier GZ is used in those rare cases when the provider expects that Medicare will deny an item or service as not reasonable and medically necessary but the provider did not obtain a valid ABN prior to the services being rendered.
Modifier GY is used when “noncovered” services such as x-rays, massage, ultrasound, and physical therapy are performed by a chiropractor and the provider elects to bill those services to Medicare. Claims billed with this modifier will be automatically denied by the Medicare claims processing system and the beneficiary will be liable for all charges, whether personally or through other insurance. Providers are required to bill “noncovered” services to Medicare when requested by the beneficiary.
