How to Get Insurance to Cover Hip or Knee Replacement Surgery

Written by Aptiva Health Editorial Team · Medically reviewed by Thomas Huhn, MD · Clinically reviewed by Simon Hoehn, DPT, PT · Reviewed by Crystal Brake, RCM Director and Taylor Sorrels, Esq. · Editorial & review standards · How we research

A joint replacement removes the worn parts of a joint and puts in new metal, plastic or ceramic parts. Total hip and total knee replacements are most often done for arthritis that has worn down the joint.

These surgeries are planned ahead, and most plans review them before they pay. This guide explains what plans usually look for, how to get the request right, and what to do if it is denied. It is part of the Coverage & Appeals Center.

Why joint replacements get denied

Joint replacement denials usually fall into one of these groups:

• Not medically necessary. The records didn’t show the plan’s criteria. See not medically necessary denials.
• No prior authorization, or approval for a different joint, side or facility. See missing prior authorization.
• Too soon. The plan wants more treatment tried first, or proof of the treatment you already had.
• Physical therapy not documented. The plan can’t see therapy notes or claims for the therapy you did.
• A health issue to address first. For example, an infection or a recent steroid shot in the joint.
• Out of network. The surgeon or hospital isn’t in your plan’s network. See out-of-network denials.

What plans usually look for

Each plan has its own written policy for joint replacement. Many plans also use a separate company to review surgery requests.

The criteria below are common examples, not rules for your plan. Ask your plan for its exact policy. Many of the examples come from one payer, Aetna, whose policies are public (Aetna CPB 0660, knee; Aetna CPB 0287, hip). Your plan may be stricter or looser.

• Pain and loss of function that limit daily life. For example, trouble walking, using stairs, sleeping or working.
• Exam findings. For example, limited motion, swelling or a limp.
• X-rays that show moderate or severe arthritis. Aetna’s knee policy, as one example, uses Kellgren-Lawrence grade 3 or 4; its hip policy uses Tönnis grade 2 or 3.
• Treatment tried first, often for about 3 months. Aetna’s policies, as one example, ask for at least 12 weeks of non-surgical treatment, or 24 weeks for some people, such as those with a BMI over 40 or under age 50.
• Physical therapy as part of that treatment. In the same Aetna policies, at least half of that treatment should be formal, in-person physical therapy in the past year, confirmed by therapy notes or claims.
• Other treatment. For example, anti-inflammatory or pain medicine, strengthening exercises, activity changes, and sometimes a cane or walker or a joint injection.
• When treatment first may not be needed. Aetna’s knee policy says conservative therapy may be inappropriate in some severe cases, such as bone-on-bone arthritis, and the chart must explain why.
• Health issues addressed first. Examples from the same policies: no active infection, no steroid injection into the joint in the 12 weeks before surgery, and, for people with diabetes, an HbA1c under 8% within 3 months before surgery.

Guidelines your clinician may cite

A 2023 guideline from the American College of Rheumatology and the American Association of Hip and Knee Surgeons looked at when to do joint replacement. It found “no evidence that delaying surgery” for more non-surgical treatment improves outcomes for people with moderate to severe arthritis who are indicated for joint replacement and have already failed non-surgical treatment (ACR: timing guideline). The same guideline sees a possible benefit in delaying surgery to cut down or stop nicotine use.

The American Academy of Orthopaedic Surgeons (AAOS) also publishes a guideline on surgery for knee arthritis, which covers topics such as blood sugar control and opioid use before knee replacement (AAOS: knee surgery guideline update).

Prehab and therapy before surgery

Some surgeons ask patients to do therapy before surgery to build strength, sometimes called “prehab.” This is separate from the therapy a plan may require before it approves surgery, though the same visits may count for both. Ask your surgeon and your plan.

If your plan limits physical therapy visits, see getting physical therapy covered.

Medicare and joint replacement

If you have Traditional Medicare, ask the surgeon’s office, or check with Medicare at 1-800-MEDICARE (1-800-633-4227), whether any prior authorization applies to your surgery.

Medicare Advantage plans usually have their own prior authorization rules. Since 2026, they must decide urgent requests within 72 hours and standard requests within 7 calendar days (CMS: CMS-0057-F fact sheet). See Medicare Advantage and Traditional Medicare.

What to ask your clinician to document

Before the request is sent, it helps if your chart clearly shows:

1. How long you have had joint pain and how it has changed.
2. How the joint limits daily life, such as walking, stairs, sleep and work.
3. Exam findings.
4. X-ray results, with the arthritis grade if your plan uses one.
5. Every treatment you have tried, for how long, and the result, including physical therapy dates and visits.
6. Any health issues and how they have been addressed, such as blood sugar, weight or nicotine use.
7. If treatment first was skipped, why it would not help.

You can ask: “Does my chart show what my plan’s joint replacement policy requires?” Bring a copy of the policy if you have it.

How to get a joint replacement covered

1. Ask whether prior authorization is needed. Call the plan or ask the surgeon’s office.
2. Get the plan’s joint replacement policy. Ask for the criteria for your joint and the exact surgery planned.
3. Count your treatment weeks. Compare the treatment you have had, including physical therapy, with what the policy asks for.
4. Gather records from other clinics. Therapy notes, injection records and X-ray reports often sit at other offices.
5. Confirm the request was sent. Get the date and reference number.
6. Check the approval details. Match the approved joint, side, facility, inpatient or outpatient setting, and dates to what is scheduled.
7. If denied, appeal quickly. Ask for a peer-to-peer review and file an internal appeal with your surgeon’s letter.

Checklist before your surgery is scheduled

• Prior authorization approved, with a reference number
• Approved joint and side match the surgery on your schedule
• Approved facility and setting (inpatient or outpatient) match your plan
• Surgery date falls inside the approved dates
• X-ray reports are in your chart
• Physical therapy notes, including from other clinics, are in your chart
• Surgeon, hospital and anesthesia are in network, or you know the cost if not
• You have a written cost estimate

What the approval should match

Sample appeal letter

You can fill in this letter by hand, or build one with the Appeal Letter Builder.

[Your name]
[Your address] · [Your phone] · [Your email]

[Date]

[Plan name or review company] — Appeals Department
[Address or fax from your denial letter]

RE: Appeal of joint replacement denial
Member name: [Name] · Member ID: [Number]
Reference / case number: [Number]
Procedure: [e.g., right total knee replacement]
Surgeon: [Name, credentials]
Date of denial: [Date]

To the Appeals Department:

I am appealing your denial of the surgery listed above. Your letter says: "[exact reason]."

I meet your criteria, [policy name or number]:
- Pain and function: [how the joint limits walking, stairs, sleep, work] — see [record, date].
- Exam findings: [findings] — see [record, date].
- X-rays: [date] show [finding, grade if known] — see report.
- Treatment tried first: [physical therapy dates and visits; medicine; injections; cane or walker] for [number] weeks — see [records].
- Health issues addressed: [e.g., HbA1c result and date; no recent joint injection] — see [records].

My surgeon's enclosed letter explains why the surgery is medically necessary and cites [guideline].

Enclosed:
- Letter of medical necessity from [surgeon]
- Visit notes and physical therapy records from [dates]
- X-ray reports from [dates]
- Your denial letter

Please approve the surgery. If you uphold the denial, please give me the specific reason, the criteria used, and the steps for external review in writing.

[If urgent:] My surgeon believes delay could harm my health. I request an expedited review.

Sincerely,
[Signature]
[Printed name]

Deadlines

Medicare has its own appeal steps (Medicare.gov: Original Medicare appeals; Medicare.gov: Medicare Advantage appeals).

To work out your own dates, try the Appeal Deadline Calculator. See Kentucky and Indiana for state steps.

What the process looks like

Here is how a joint replacement request usually moves. Your plan may differ.

1. Your surgeon recommends a joint replacement and documents why.
2. The surgeon’s office sends the prior authorization request to your plan or its review company, often weeks before the surgery date.
3. The plan reviews it against its joint replacement policy. Plans covered by the 2026 federal rule must decide within 7 calendar days, or 72 hours if urgent.
4. The plan approves, asks for more information, or denies. A request for more information is not a denial. Respond quickly.
5. If approved, you schedule surgery within the approved dates, at the approved facility and setting.
6. If denied, your surgeon can ask for a peer-to-peer and you can file an appeal.

An example

*This is an illustrative example, not a real patient.*

Robin has knee arthritis. Walking a block hurts, and stairs are hard. Robin’s surgeon requests a total knee replacement. The plan denies it: “insufficient conservative treatment.”

Robin had done physical therapy for two months the year before, plus medicine and a knee injection. But the therapy was at another clinic, and the request listed only the injection. Robin gets the therapy notes, and the surgeon writes a letter that counts the weeks of each treatment and describes the X-ray. Robin appeals with the letter and records.

The lesson: count your treatment weeks against the policy, and make sure every record is in the file.

Questions to ask before your surgery

• “Does my plan need prior authorization for this surgery?”
• “How many weeks of treatment does my plan’s policy ask for, and do I have them?”
• “Do you have my physical therapy notes from other clinics?”
• “Is the surgery approved as inpatient or outpatient? At which facility?”
• “Are the surgeon, hospital and anesthesia in my network?”
• “What is my cost after insurance, including therapy after surgery?”

Common mistakes

• Scheduling before approval comes through. If the plan denies it later, you may owe the bill.
• Missing therapy notes, especially from another clinic.
• Not counting treatment weeks. A request sent a few weeks early may be denied as “too soon.”
• Forgetting the setting. An approval for outpatient surgery may not cover an inpatient stay.
• Not asking about a peer-to-peer. It can be faster than a written appeal.

If your joint replacement is denied

Read the denial letter closely. The Denial Decoder can help you understand the codes and wording.

Since January 1, 2026, Medicare Advantage, Medicaid, CHIP and HealthCare.gov Marketplace plans must give a specific reason when they deny a prior authorization request (CMS: CMS-0057-F fact sheet). A vague reason makes an appeal harder, so it is fair to ask for more detail.

Check that the letter tells you:

• The exact service that was denied and the date.
• The specific reason, in words you can act on.
• The policy or criteria the plan used. If it doesn’t, ask for a free copy (29 CFR 2560.503-1(g)(1)(v); 45 CFR 147.136(b)).
• Your deadline to appeal and how to send it.
• How to ask for an expedited review if it’s urgent.
• How to ask for an external review if the internal appeal fails.

If anything is missing, call the plan, ask for it in writing, and write down the date, the name of the person you spoke with, and a reference number.

Costs and your deductible while you wait

An appeal can take weeks. Meanwhile, it helps to understand what you might owe either way.

• If the appeal succeeds, the plan pays under your normal benefits. You still owe any deductible, copay or coinsurance.
• If you go ahead before a decision, you may owe the full bill if the appeal fails. Ask for a written cost estimate first.
• Check your EOB (explanation of benefits) when each claim is processed. Surgery often brings several bills: surgeon, facility and anesthesia.
• Ask about payment plans if a large bill arrives during the appeal. Ask the billing office to hold the account while the appeal is open.

If coverage doesn’t work out

• Ask for an external review after a final internal denial.
• Ask about a cash-pay price, and get it in writing.
• Talk with your surgeon about other treatment while you appeal, such as physical therapy.

Before paying cash, ask how it affects your deductible. Cash payments may not count toward it unless your plan allows that.