Surgical arthroplasty of a finger interphalangeal joint — one unit per joint treated.

Verified May 8, 2026 · 5 sources ↓

Medicare: $419.85
Work RVU: 5.27
Global, days: 90
Region: Hand

Drawn from CMSAAPCNIHMdclarity

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 5 cited references ↓

Specify which finger and which joint (PIP vs. DIP) by name — 'interphalangeal joint' alone is insufficient for audit purposes.
Document conservative treatment failure prior to surgery (splinting, NSAIDs, injections) to support medical necessity.
Operative note must describe the reconstructive technique: implant type and size or resection/repair method used.
Preoperative imaging (X-ray or MRI) confirming arthritic destruction or deformity must be in the record.
If multiple joints were treated in the same session, each joint requires its own documentation entry and corresponding finger modifier on the claim.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 25 Significant separate E/M 51 Multiple procedures 52 Reduced services 58 Staged or related 59 Distinct service 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant LT Left side RT Right side XS Separate structure

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

26535 covers arthroplasty of a single interphalangeal (IP) joint of the finger, whether proximal (PIP) or distal (DIP). The surgeon resects damaged joint surfaces and either implants a prosthetic spacer or performs other reconstructive work to restore motion and relieve pain. Typical indications include severe osteoarthritis, post-traumatic arthritis, or joint deformity unresponsive to conservative care.

26535 is finger-only. Coding it for a toe IP arthroplasty is incorrect — use 28899 (unlisted foot/toes) instead. Because the descriptor reads 'each joint,' you report one unit per joint with the appropriate finger modifier (F1–F9 or FA). MUE values for this code are built around that per-finger modifier logic, so billing multiple units on a single line without distinct finger modifiers will trigger a denial.

The 90-day global period means the operative day, the day-before pre-op visit, and all routine post-op follow-up through day 90 are bundled into the single fee. Use modifier 24 for unrelated E/M visits in that window, and modifier 78 for any unplanned return to the OR for a related complication during the global.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU vs. total RVU

The work RVU (5.27) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (12.57) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	5.27
Practice expense RVU	6.3
Malpractice RVU	1
Total RVU	12.57
Medicare national rate	$419.85
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$419.85
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI A2) Ambulatory surgical center (freestanding)	$1,644.87

Common denial reasons

The recurring reasons claims for CPT 26535 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Wrong body region: 26535 billed for a toe IP arthroplasty — payers reject this; use 28899 for toe procedures.
Missing or mismatched finger modifier (FA, F1–F9) when multiple joints are billed on the same date of service.
Insufficient medical necessity documentation — no evidence of failed conservative treatment before surgery.
Bundling conflict when ancillary soft-tissue repairs performed at the same joint are billed without a distinct modifier establishing separate service.
Global period violation — post-op E/M visits billed without modifier 24 when unrelated, or without modifier 78 for a return to the OR.

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01Can 26535 be used for a toe interphalangeal arthroplasty?

No. 26535 is restricted to finger IP joints. For a toe IP arthroplasty, report 28899 (unlisted foot/toes procedure) and attach an operative report.

02How do you bill 26535 when the surgeon operates on two fingers in the same session?

Report 26535 once for each joint with the appropriate finger modifier (e.g., F1 for left index, F2 for left long). Use modifier 51 on the second and subsequent procedures to indicate multiple surgeries. Each line needs its own finger modifier or Medicare will deny on MUE grounds.

03What is the global period for 26535, and what does it include?

26535 carries a 90-day global period. That bundles the surgery itself, the day-before pre-op visit, and all routine post-op care through day 90. Splint checks, suture removal, and standard wound care in that window are not separately billable.

04Is modifier 50 appropriate for 26535 on bilateral finger procedures?

Bilateral symmetric IP arthroplasty in the same session is rare, but if it occurs, physicians report modifier 50 on a single claim line per CMS bilateral surgery rules. ASCs report two lines with LT and RT instead.

05When is modifier 22 appropriate with 26535?

Use modifier 22 when the procedure is substantially more complex than typical — for example, severe post-traumatic deformity with extensive scar tissue requiring prolonged dissection. Document the additional time and complexity in the operative note; without that documentation, payers will deny the increased-complexity claim.

06What distinguishes 26535 from 26536?

26535 covers arthroplasty without an implant (or with certain implant types); 26536 specifically describes arthroplasty with a prosthetic implant. Verify the correct code based on whether a prosthetic device was placed — using 26535 when an implant was inserted is a coding error that can surface on audit.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the specific finger (e.g., index, long), joint level (PIP or DIP), the surgical technique (implant arthroplasty vs. resection arthroplasty), implant brand and size if used, and the laterality — all from dictation. That structured capture prevents the most common audit flag: an operative note that says 'interphalangeal arthroplasty' without identifying which finger or what was done to the joint surface.

See how Mira captures CPT 26535 documentation