Medicare's coverage of subchondroplasty depends on your plan type and whether your doctor orders it as medically necessary

Subchondroplasty is a procedure in which a surgeon injects a special material under damaged cartilage in a joint — usually the knee — to fill a cavity and reduce pain. Original Medicare (Part A and Part B) does not routinely cover subchondroplasty, though some Medicare Advantage plans may. The procedure is still relatively new, and Medicare's national coverage information treats it as investigational, meaning it falls outside standard coverage unless your specific situation meets narrow criteria.

Whether you can get coverage depends on three things: which type of Medicare you have, whether your doctor can document that the procedure is medically necessary for your condition, and whether your plan or a clinical trial has made an exception. This is not a yes-or-no answer across all of Medicare — it varies by plan and by individual case.

Key Takeaways

  • Original Medicare does not cover subchondroplasty as a standard benefit, though your doctor can request a coverage exception if they believe it is medically necessary for your condition.
  • Medicare Advantage plans set their own coverage rules and may cover subchondroplasty; you will need to contact your specific plan to ask.
  • Some academic medical centers and hospitals offer subchondroplasty through clinical trials, which may be an option if standard coverage is denied.
  • Your doctor must document that you have a bone marrow lesion or cartilage defect and that other treatments have not worked before any coverage request has a realistic chance.

How Original Medicare treats subchondroplasty

Original Medicare classifies subchondroplasty as an investigational procedure, which means it does not automatically pay for it. However, this does not mean you cannot receive coverage — it means your doctor has to make a case that the procedure is necessary for your particular condition and that standard treatments have not worked.

To request coverage, your doctor submits what is called a coverage information request to Medicare. This request must include imaging (usually an MRI) showing a bone marrow lesion or cartilage defect, documentation that you have tried other treatments like physical therapy or injections, and an explanation of why subchondroplasty is the appropriate next step. Medicare then reviews the request and decides whether to cover it in your case. This process typically takes two to four weeks.

Even if Medicare denies the initial request, your doctor can appeal. An appeal goes to a Medicare Administrative Contractor (MAC), which is the regional office that handles claims for your state. The appeal process can take several weeks longer, and you have the right to request a hearing if the MAC denies coverage again.

Medicare Advantage plans and subchondroplasty coverage

Medicare Advantage plans (Part C) are run by private insurance companies and set their own coverage rules within Medicare guidelines. Some Advantage plans do cover subchondroplasty, while others do not. There is no single answer across all Advantage plans.

To find out whether your Advantage plan covers the procedure, call the customer service number on your insurance card and ask directly: "Does my plan cover subchondroplasty for knee pain?" Have your doctor's name and the specific diagnosis ready. If the plan says no, ask whether your doctor can request a coverage exception — many plans allow this if the doctor provides medical justification.

If your Advantage plan denies coverage and your doctor believes the procedure is medically necessary, you have the right to appeal. The appeal process is similar to Original Medicare but goes through your Advantage plan's appeals department rather than a MAC.

What you need before requesting coverage

Medicare and most insurance plans will not even consider a coverage request for subchondroplasty without specific documentation. Your doctor needs to have on file:

  • An MRI showing a bone marrow lesion, cartilage defect, or osteochondral lesion in the joint being treated.
  • Records showing you have tried and failed at least one other treatment — usually physical therapy, corticosteroid injection, or hyaluronic acid injection — over a period of weeks or months.
  • Documentation that you have persistent pain or functional limitation despite these treatments.
  • A written explanation from your surgeon about why subchondroplasty is the appropriate next step for your specific condition.

If your doctor has not ordered an MRI yet, that is the first step. Without imaging evidence of the lesion, no coverage request will succeed. If you have tried only one other treatment, your doctor may recommend waiting a few more weeks or trying another conservative option before submitting a coverage request, because Medicare reviewers are more likely to approve when multiple treatments have been attempted.

Clinical trials as an alternative if coverage is denied

If Medicare or your Advantage plan denies coverage, some hospitals and academic medical centers offer subchondroplasty through clinical trials. In a clinical trial, the procedure may be performed at no cost to you as part of a research study. Your doctor can search for active trials at ClinicalTrials.gov, a database maintained by the National Institutes of Health.

To find trials near you, go to ClinicalTrials.gov, search for "subchondroplasty," and filter by location and status. Trials marked "Recruiting" or "Enrolling by Invitation" are actively looking for participants. Contact the trial site directly to ask whether you meet their criteria and whether your condition fits the study.

Clinical trials are not a may provide — you have to meet the study's specific criteria, and the trial has to be enrolling at a location you can reach. But if standard coverage is not available, a trial can be a real option to explore with your doctor.

What happens if Medicare or your plan says no

If your initial coverage request is denied, you have options. First, ask your doctor whether the denial was based on missing information — sometimes a resubmission with additional medical records succeeds where the first request did not. Second, you can appeal the decision. For Original Medicare, the appeal goes to your regional Medicare Administrative Contractor. For Advantage plans, it goes to your plan's appeals department.

You also have the right to request an independent review if you disagree with the appeal decision. This is called an external review for Advantage plans and a reconsideration for Original Medicare. Your doctor's office can help you file these requests, and you do not pay a fee to appeal.

Finally, if you decide to have the procedure done anyway and pay out of pocket, ask your surgeon's office for the cost upfront. Subchondroplasty costs vary widely depending on the facility and your location, but you should expect to pay several thousand dollars. Some surgeons' offices offer payment plans.

Questions to ask your doctor before pursuing coverage

Before your doctor submits a coverage request, have a conversation about realistic expectations. Ask: "Do you think Medicare will cover this based on my specific situation?" "How long will the coverage request take, and what should I do about my pain in the meantime?" "If Medicare says no, do you think it's worth appealing, or should we try another treatment first?" "Are there any clinical trials I might be may be able to access for?"

Your doctor knows your medical history and imaging results better than anyone. They can give you an honest sense of whether a coverage request is likely to succeed and what your options are if it does not. This conversation also helps you decide whether to wait for a coverage decision or pursue other treatments while the request is being reviewed.

Frequently Asked Questions

Will Medicare cover subchondroplasty if my doctor says it's medically necessary?

Not automatically. Original Medicare treats subchondroplasty as investigational, so your doctor has to submit a coverage information request with medical documentation. Medicare will review it, but there is no may provide of approval even if your doctor believes it is necessary. Medicare Advantage plans have their own rules and may cover it; you need to ask your specific plan.

How long does a Medicare coverage request take?

The initial review usually takes two to four weeks. If Medicare denies the request and your doctor appeals, the appeal process can take several weeks longer. During this time, you can pursue other treatments for pain management.

What if I have already had subchondroplasty and paid out of pocket — can I get reimbursed?

Reimbursement after the fact is unlikely, but you can ask. Contact your Medicare Administrative Contractor or your Advantage plan's appeals department with your surgery records and ask whether they will reconsider coverage retroactively. Some plans will not; others may if your doctor's documentation supports medical necessity.

Does it matter which knee surgeon I see for subchondroplasty?

Yes. Surgeons who perform subchondroplasty regularly have more experience documenting the medical necessity and submitting coverage requests successfully. Ask your primary care doctor or orthopedic specialist whether they can refer you to a surgeon who has experience with both the procedure and Medicare coverage requests.

Can I appeal a Medicare Advantage plan's denial of subchondroplasty?

Yes. You have the right to appeal any coverage denial. Your plan must provide you with a written explanation of why they denied coverage and instructions for appealing. You can also request an external review, which is an independent review of your plan's decision by a third party.