Glossary · Billing

Appeal

An appeal is a formal request to a payer to reconsider a claim that was denied, underpaid, or otherwise decided unfavorably. In orthopedic billing, appeals are commonly triggered by bundling edits, medical-necessity denials, and site-of-service disputes.

Verified May 8, 2026 · 8 sources ↓

Drawn from AAOSCMSMedicare.govAAPC42 CFR

Definition

Source · Editorial summary grounded in 8 cited references ↓

When a Medicare Administrative Contractor (MAC), Medicare Advantage plan, or commercial payer issues an unfavorable coverage or payment determination, the provider, supplier, or beneficiary has the right to challenge that decision through a structured appeals process. For Original Medicare, the process runs through five escalating levels: redetermination (MAC), reconsideration (Qualified Independent Contractor), Administrative Law Judge (ALJ) hearing, Medicare Appeals Council review, and federal district court. Timeframes matter: most redetermination requests must be filed within 120 days of the initial determination notice, and each subsequent level carries its own deadline. Medicare Advantage plans follow parallel requirements under 42 CFR Part 422, Subpart M, which govern organization determinations and multi-level appeals for MA enrollees.

In orthopedic practice, denials frequently stem from National Correct Coding Initiative (NCCI) bundling edits, modifier misuse (particularly modifiers 25 and 59), downcoding of evaluation and management services, and prior-authorization disputes—especially for procedures such as total knee arthroplasty (CPT 27447) after its removal from the Medicare Inpatient-Only list in 2018. A successful appeal requires submitting the original claim documentation alongside supporting evidence: operative reports, medical records, relevant CPT and CMS coding guidelines, and, where available, AAOS-developed appeal letter templates or Complete Global Service Data.

The AAOS Coding, Coverage & Reimbursement Committee (CCRC) actively develops standardized resources—template appeal letters, FAQs, and downcoding action guides—to help orthopedic surgeons challenge inappropriate denials systematically. Using these resources strengthens appeals by anchoring arguments in published CPT guidance and CMS policy rather than practice-specific assertions alone.

Why it matters

Failing to appeal a denial is, in effect, writing off legitimate revenue. For high-RVU orthopedic procedures—TKA, shoulder arthroscopy, complex fracture repair—even a single uncontested denial can represent thousands of dollars in lost reimbursement per case. Beyond individual claims, a pattern of unappealed denials can signal to payers that a practice accepts bundling or downcoding decisions without scrutiny, inviting future edits. On the compliance side, an appeal creates a documented record that the practice disagreed with a payer's determination, which matters during audits; silence after a denial can be read as tacit acceptance of an incorrect coding position.

Common mistakes

Where people most often go wrong with this concept.

Source · Editorial brief grounded in cited references ↓

Missing the 120-day redetermination deadline for Original Medicare because the date is counted from the initial determination notice, not the remittance advice posting date.
Submitting a bare appeal letter without attaching the operative report, office notes, or relevant NCCI policy documentation—reviewers can only rule on evidence in the case file.
Conflating a grievance (quality-of-care complaint) with an appeal (coverage or payment dispute), which routes the request to the wrong department and restarts the clock.
Appealing a bundled code denial without first verifying whether an appropriate modifier (e.g., modifier 59 or an X{EPSU} modifier) was correctly applied on the original claim—an omitted modifier is correctable at redetermination, not solely through appeal.
Assuming one appeal letter template fits all payers; Medicare Advantage plans operate under their own organization-determination rules, and commercial payers have contract-specific appeal procedures that differ from Original Medicare's five-level structure.
Overlooking AAOS-provided specialty-specific appeal resources for high-denial procedures like TKA (CPT 27447) and shoulder arthroscopy, which include pre-built clinical justification language and letters sent by AAOS to CMS.

Related codes

Codes commonly involved when this concept appears in practice.

CPT

ICD-10

M17.11 M17.12

Modifiers

25 Significant separately identifiable E/M 59 Distinct procedural service XS Separate structure 76 Repeat procedure same physician KX Medical-policy requirements met

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 8 cited references ↓

01How long does a provider have to file a Medicare redetermination request?

The deadline is 120 days from the date of the initial determination notice. This clock starts from the notice date, not from when the remittance advice is posted or processed internally—a distinction that catches many practices off guard.

02What is the difference between a Medicare appeal and a Medicare Advantage appeal?

Original Medicare appeals follow a five-level federal process governed by CMS. Medicare Advantage appeals are governed by 42 CFR Part 422, Subpart M, and begin with an organization determination by the MA plan itself before escalating to external review. Deadlines, decision timeframes, and the entities reviewing the appeal differ between the two tracks.

03Can a billing service file a Medicare appeal on behalf of a practice?

Yes. Per CMS guidance, billing clerks or billing services employed by the provider act as the provider's agent and do not need a separate appointment of representative. They are appealing on behalf of the provider or supplier, not the beneficiary.

04Does AAOS provide ready-made appeal resources for orthopedic-specific denials?

Yes. The AAOS Coding, Coverage & Reimbursement Committee maintains appeal letter templates, FAQs, and procedure-specific resources for high-denial codes including TKA (CPT 27447) and shoulder arthroscopy. These materials are available through the AAOS coding and reimbursement pages and are grounded in CPT and CMS policy language.

05What documentation should be included in an orthopedic appeal?

At minimum: the operative or procedure report, relevant office notes establishing medical necessity, the remittance advice showing the denial reason code, and a written argument citing applicable CPT guidelines, CMS policy, or NCCI edit rules. AAOS Complete Global Service Data content can bolster arguments about bundling or global package disputes.

06Can minor claim errors—like a wrong place-of-service code—be resolved through appeal?

Yes. CMS permits telephone reviews for straightforward corrections including place-of-service errors, modifier additions or changes, erroneous duplicate denials, and unit count discrepancies, provided an initial determination has already been issued on the claim.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira can support the appeals workflow at the documentation layer—the point where most appeals are won or lost. When Mira detects that a procedure, modifier combination, or E/M level is at elevated denial risk (e.g., modifier 25 appended to a same-day E/M with a procedure, or CPT 27447 billed in an outpatient setting), it flags the documentation gap in real time so the note can be strengthened before claim submission. Proactive documentation—clear medical necessity language, explicit separation of the E/M decision from the surgical indication, and site-of-service justification—is the most efficient appeal strategy because it reduces the need for retrospective appeals entirely. If a claim is denied post-submission, Mira's documentation record provides a ready-made evidence base: the structured operative note, the pre-visit assessment supporting medical necessity, and the modifier rationale are already captured in retrievable form. This output can be attached directly to a redetermination request alongside AAOS appeal letter templates. Mira does not file appeals or interact with payer portals, but the structured clinical documentation it generates aligns with the evidentiary requirements of CMS redetermination reviewers and Qualified Independent Contractors.

See Mira's approach

A redetermination is the first of five Medicare appeal levels, in which a Medicare Administrative Contractor (MAC) conducts a fresh review of a denied or partially paid claim; the request must be filed within 120 days of receiving the initial determination notice.

Reconsideration (Medicare appeal level 2) Billing

Reconsideration is the second of five Medicare appeal levels, in which a Qualified Independent Contractor (QIC)—entirely separate from the MAC that issued the original denial—conducts an independent review of the full administrative record and renders a new decision. It must be requested within 180 days of receiving the redetermination notice.

Prior authorization Billing

Prior authorization (PA) is a payer requirement that a provider obtain approval before delivering a specific service, procedure, or item—otherwise the claim will be denied regardless of medical necessity. Approval is granted when submitted clinical documentation meets the payer's coverage criteria.

Medicare Administrative Contractor (MAC) Compliance

A Medicare Administrative Contractor (MAC) is a private insurance company under contract with CMS to process and pay Medicare Part A and Part B fee-for-service claims within an assigned geographic jurisdiction. MACs are the primary point of contact for providers on coverage policies, claims adjudication, and local coverage determinations.