How Rette helps

The Wasteful and Inappropriate Service Reduction (WISeR) Model is a CMS Innovation Center test of technology-assisted prior authorization in Original Medicare. It began January 1, 2026, and runs through December 31, 2031. WISeR does not change Medicare coverage rules or payment rates. It changes when and how existing national and local coverage determination (NCD and LCD) criteria are checked.

For orthopedic and spine practices, the list is short but includes high-volume services: knee arthroscopy for osteoarthritis, epidural steroid injections and several spine procedures. This guide reflects CMS’s WISeR Provider and Supplier Operational Guide, version 7.0, dated July 24, 2026. CMS can update the list during the model, so check the current version before you build workflows.

Which states does WISeR cover, and who reviews requests?

WISeR applies when an Original Medicare patient receives a listed service in one of these states. Medicare Advantage and Railroad Medicare patients are excluded, and so are providers under review by a Unified Program Integrity Contractor. Participants and MACs began accepting requests on January 5, 2026, for services on or after January 15, 2026.

The participants are technology companies that combine AI and machine learning with clinical reviewers. Technology can speed approvals, but a licensed clinician with relevant expertise must review every non-affirmation before it is issued. CMS pays participants a share of the spending they avert, adjusted for timeliness, accuracy and provider experience, and it withholds or recoups that payment when a non-affirmed service later wins on appeal.

Which orthopedic services are on the WISeR list?

In plain terms, 29877 is arthroscopic chondroplasty, the smoothing or shaving of damaged knee cartilage. 62321 and 62323 are interlaminar epidural injections with imaging guidance in the neck or upper back and the lower back. 64479 to 64484 are transforaminal epidural injections with imaging guidance, first and additional levels. 22510 to 22515 cover vertebroplasty and kyphoplasty-type augmentation, 22554 is an anterior cervical interbody fusion below C2, and 63655 places paddle spinal cord stimulator electrodes through a laminectomy.

Total hip and knee replacement, fracture care and joint injections such as 20610 are not on the list as of the July 24, 2026 guide. Other WISeR services, including skin and tissue substitutes for lower-extremity wounds (only where an active LCD applies), hypoglossal and sacral nerve stimulation, and incontinence devices, matter more to wound care, sleep medicine and urology.

Which sites of service and claims are affected?

WISeR covers the office (POS 11), home (POS 12), ambulatory surgery centers (POS 24) and hospital outpatient departments. In ASCs and hospital outpatient departments, review attaches to the facility claim. In the office, it attaches to your professional claim. Inpatient-only and emergency services are excluded.

The guide also lists associated codes, such as anesthesia, the femoral nerve block 64447 and the meniscectomy codes for knee arthroscopy. They don’t need their own request, but they are denied or recouped if the primary service is non-affirmed or denied. A surgeon’s professional claim can therefore be denied when the ASC’s facility claim fails review.

What documentation does CMS expect?

For knee arthroscopy, CMS’s checklist asks for documentation of less severe or early degenerative arthritis with symptoms beyond pain alone, such as locking, catching or popping, plus standing x-ray and MRI reports. NCD 150.9 already makes arthroscopic lavage alone, and debridement for pain-only presentations or severe (Outerbridge grade III or IV) osteoarthritis, nationally noncovered.

For epidural steroid injections, it asks for radiculopathy, radicular pain or neurogenic claudication supported by history, exam and imaging; at least 4 weeks of pain with failed or poorly tolerated conservative care; a baseline pain or function scale repeated at follow-up; no more than four sessions per spinal region in a rolling 12 months; and the planned image guidance, approach and levels.

How do you submit a WISeR prior authorization request?

You can send a request directly to your state’s WISeR participant through its portal, by fax or by mail. You can also send it to your MAC by fax, esMD, mail or the MAC portal, and the MAC forwards it within one calendar day. Physicians may submit on behalf of the ASC or hospital that will bill the facility claim.

Each request covers one WISeR service and must include:

• Patient name, Medicare number (MBI), date of birth and address

• Facility name, address, NPI and PTAN or CCN, when a facility is involved

• Physician name, NPI, PTAN and address, plus the requester’s contact details

• CPT or HCPCS codes, diagnosis codes, place of service and units to be performed within 120 days

• Whether it is an initial request or a resubmission, and whether expedited review is needed and why

• Clinical documentation that meets the NCD or LCD criteria

Participants typically decide within 3 calendar days of receiving a request. Expedited requests are decided within 2 days when a delay could seriously jeopardize the patient’s life, health or ability to regain maximum function. Resubmissions are unlimited.

Every decision carries a MAC-generated unique tracking number (UTN), valid for 120 calendar days from the decision. Report it on the claim whether the decision was affirmed or not, in loop 2300 REF (qualifier G1) of an 837P or the first 14 positions of item 23 on a paper CMS-1500. For ASC and hospital outpatient services, the UTN goes on the facility claim.

What happens if you skip prior authorization?

Requesting prior authorization is voluntary. If you bill a WISeR service without a decision on file, the MAC suspends the claim and the participant performs pre-payment medical review. You receive an additional documentation request (ADR) and have 45 days to respond, and the participant sends its decision to the MAC within 3 days of receiving the records. If you miss the 45-day window, the claim is denied.

A claim billed after a non-affirmation is denied, with normal Medicare appeal rights. If the patient still wants the service, CMS says to deliver an Advance Beneficiary Notice before providing it and bill with modifier GA. An affirmation is not a payment guarantee: claims can still deny for technical errors or new information, although affirmed claims get some protection from later audits. For broader denial patterns, see the most common orthopedic claim denials.

Can your surgeons earn a WISeR exemption, or gold card?

Yes. Since July 2026, participants automatically exempt individual NPIs that demonstrate compliance. CMS’s minimum criteria are at least 10 prior authorization requests across WISeR services during an assessment period and a minimum affirmation rate, which each participant sets and publishes.

Exemptions are added quarterly, last at least a year and cover all WISeR services and sites of care. Participants reevaluate them with no more than 10 ADRs per year and give at least 60 days’ notice before removing a provider. On claims, report the exempt NPI as the rendering provider in the office or home, the referring or ordering provider on ASC claims, and the operating provider on hospital outpatient claims.

How should an orthopedic practice build a WISeR workflow?

1. Screen at scheduling: Original Medicare (not Medicare Advantage or Railroad Medicare), a service delivered in a WISeR state and a primary code from the WISeR list.

2. Choose a pathway by service line. For planned knee arthroscopy and spine procedures, prior authorization gives you a coverage decision before the case; pre-payment review leaves payment at risk after the service.

3. Build note templates from CMS’s checklists so they capture mechanical symptoms, imaging, conservative care, pain or function scores and session counts.

4. Agree with each ASC and hospital on who submits the request, who receives the UTN and how it reaches the facility claim.

5. Track UTN expiration. If surgery moves beyond 120 days, submit a new request.

6. Work non-affirmations quickly: read the rationale, add missing records, request peer-to-peer review and resubmit, or deliver an ABN if the patient chooses to proceed.

7. Calendar every ADR’s 45-day deadline.

8. Track affirmation rates by surgeon to see who is close to exemption.

Keep WISeR separate from Medicare Advantage prior authorization, which follows each plan’s rules and the CMS Interoperability and Prior Authorization Final Rule. For other 2027 Medicare changes, see our CY 2027 Physician Fee Schedule overview.

How Rette helps

Rette’s agents read the operative and clinical notes in the EHR your practice already uses and check documentation against NCD and LCD criteria before a request or claim goes out. Prior authorization, denials, appeals and workers’ compensation work sit in one prioritized queue, so WISeR requests, ADR deadlines and resubmissions are tracked alongside your other payer work.