Billing code 26531: Knuckle arthroplastyMedicare rate & RVUs in Oregon
Reports implant arthroplasty of a metacarpophalangeal joint to address painful joint destruction or deformity while preserving finger motion.
CMS doesn’t publish an office rate for 26531 in Oregon.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 26531 covers
A hand surgeon removes damaged joint surfaces at a metacarpophalangeal (MCP) joint and places an implant to improve alignment and preserve motion. Typical cases include painful MCP destruction and deformity from rheumatoid arthritis, or joint damage from other causes. The procedure is generally performed in an operating room, with the specific finger and joint identified in the operative report.
Report this code when the operation includes an implant at the MCP joint; distinguish it from MCP arthroplasty without an implant and implant arthroplasty at a finger interphalangeal joint. Documentation should establish the treated joint, the underlying problem, and implant placement. Medicare assigns a 90-day global period, including the day-before preoperative visit and related postoperative care during that period. When multiple procedures are performed in one session, the highest-valued procedure is paid in full and other procedures are subject to the standard reduction. Modifier 50 is inappropriate. Assistant-at-surgery payment may be available; co-surgeon payment requires supporting documentation, and team surgery is not permitted.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 26531 pays more and less in Oregon
| Payment locality | Office | Facility |
|---|---|---|
| Portland | Unavailable | $610.05 |
| Rest Of Oregon | Unavailable | $572.31 |
How the 26531 rate is calculated
Each of 26531’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 26531
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 7.93Practice expense 8.19Malpractice 1.49
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 26531
26531 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 26531
Knuckle arthroplasty
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 090 | Major surgery: the day before, the day of, and 90 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.10/0.69/0.21 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 26531
Knuckle arthroplasty
90-day global period ends
Dec 30, 2026
Covers Sep 30, 2026 through Dec 30, 2026 (92 days, including the day before surgery).
Visit on Oct 31, 2026
Day 30 of the 90-day post-op period: related follow-up care is included in the surgical payment.
Pre-op dayGlobal period
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
26531 without 51 · national facility
$588.19
Knuckle arthroplasty
26531-51 · Second procedure: 50%
$294.10
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
26531 compared with similar codes
Compare codes
26531 vs 26530 vs 26536 vs 26516: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 26530Knuckle arthroplasty
- Both address MCP joint arthroplasty, but 26531 includes implant placement; 26530 is for arthroplasty without an implant.
- 26536Finger joint arthroplasty
- Both involve implant arthroplasty, but 26536 is for a finger interphalangeal joint. Use 26531 for an MCP joint.
- 26516Knuckle fusion
- This code describes fusion of an MCP joint. Choose it when the operation fuses the joint, not when an implant arthroplasty is performed.
26531 billing questions
How does this differ from 26530?
Use 26531 when an implant is placed during MCP joint arthroplasty. Code 26530 describes MCP arthroplasty without an implant.
Can this code be used for an implant at a finger joint?
No. This code is for a metacarpophalangeal joint. Code 26536 describes implant arthroplasty at an interphalangeal joint.
Should modifier 50 be reported when both hands are treated?
No. CMS identifies bilateral adjustment as inappropriate for this code. Follow the applicable reporting instructions for the procedures performed on each hand.
What postoperative care is included?
The 90-day global period includes the day-before preoperative visit and related postoperative care for 90 days after surgery.
Can an assistant surgeon or co-surgeon be reported?
Assistant-at-surgery payment may be available. Co-surgeon payment requires supporting documentation; team surgery is not permitted.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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