Partial excision of the ulna — removing a section of ulnar bone using craterization, saucerization, or diaphysectomy technique, typically to address osteomyelitis or other focal bone disease.

Verified May 8, 2026 · 7 sources ↓

Medicare: $534.75
Total RVUs: 16.01
Global, days: 90
Region: Wrist

Drawn from CMSFastrvuAAPCGenhealthMedicaid

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Specify the surgical technique used: craterization, saucerization, or diaphysectomy — not just 'partial excision'
Document the indication explicitly (e.g., osteomyelitis, necrotic bone, chronic infection) with supporting imaging or pathology correlation
Record the extent of bone removed and confirm the ulna — not radius — is the operative site
Include intraoperative findings describing the appearance of the diseased bone and soft tissue involvement
If cultures or bone specimens were sent, document pathology/microbiology orders to support medical necessity
For osteomyelitis cases, note prior failed conservative or antibiotic treatment to support surgical necessity

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 LT Left side RT Right side XS Separate structure

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

CPT 25150 covers partial removal of the ulna via craterization, saucerization, or diaphysectomy — techniques that leave a concave defect in the bone after diseased, infected, or necrotic tissue is excised. The classic indication is chronic osteomyelitis of the ulna, though the code also applies to other focal pathology requiring surgical debridement of ulnar bone. The procedure does not include the complete distal ulna resection performed under 25240 (Darrach procedure); if you remove the entire distal ulna, 25150 is the wrong code.

The 90-day global period means all routine postoperative care — wound checks, dressing changes, suture removal, and follow-up visits for the operative condition — is bundled through day 90. Separate billing during that window requires modifier 24 (unrelated E/M) or 79 (unrelated procedure). If the patient returns for an unplanned procedure related to a complication of this excision, bill that return with modifier 78.

The companion code for a comparable radius procedure is 25151. If both bones are operated on at the same session, report each code with the appropriate LT/RT modifier rather than modifier 50, since the radius and ulna are distinct anatomic structures — not bilateral paired organs.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	7.2
Practice expense RVU	7.37
Malpractice RVU	1.44
Total RVU	16.01
Medicare national rate	$534.75
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	$534.75
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 25150 get rejected.

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

Medical necessity not established — no documentation of failed conservative treatment, supporting imaging, or confirmed bone pathology
Incorrect code selection: 25150 billed when operative note describes complete distal ulna resection (Darrach), which maps to 25240
Unbundling with 25151 (radius) without LT/RT modifiers to distinguish operative sites
Global period violation — postoperative E/M billed without modifier 24 or 25 within the 90-day window
Missing laterality modifier (LT or RT) causing claim rejection or payer-level edit failures

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 7 cited references ↓

01What's the difference between 25150 and 25240?

25150 is a partial excision — the surgeon removes a diseased section of the ulna while leaving the bone structurally present. 25240 is the Darrach procedure: complete resection of the distal ulna. If your operative note describes full removal of the distal segment, 25150 undercodes the work.

02Can I bill 25150 and 25151 together when both forearm bones are operated on?

Yes — 25150 (ulna) and 25151 (radius) are distinct anatomic procedures. Apply LT and RT modifiers or document bilateral involvement clearly. Do not use modifier 50; these are separate bones, not a bilateral paired structure.

03What ICD-10 codes typically support 25150?

Chronic osteomyelitis of the forearm (M86.63x) is the primary driver. Also supported by acute hematogenous osteomyelitis of the forearm (M86.13x) and other bone infection or necrosis codes specific to the ulna. Payers will scrutinize any diagnosis that doesn't reflect bone pathology — soft tissue infection alone won't support this code.

04Is this procedure typically done in an ASC or hospital outpatient setting?

Both are used. The ASC and HOPD payments differ materially — see the Site of Service comparison on this page. Complex osteomyelitis cases with significant soft tissue involvement often migrate to the hospital outpatient or inpatient setting based on the need for IV antibiotics and wound management post-op.

05If the patient returns within 90 days for wound debridement related to this surgery, how do I bill?

Use modifier 78 — unplanned return to the OR for a complication or directly related condition during the global period. Modifier 79 is for unrelated procedures. Inverting these modifiers is a common audit flag.

06Does the 90-day global include the bone pathology follow-up and IV antibiotic management?

Routine post-op visits are bundled. However, if the patient requires ongoing infectious disease management or E/M visits for a condition unrelated to the operative site, those can be billed separately with modifier 24. The key test: is the visit for the surgical condition or something distinct?

Sources & references

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

Mira AI Scribe

Mira's AI scribe captures the technique name (craterization, saucerization, or diaphysectomy), the bone confirmed as ulna, the pathologic indication, extent of resection, and intraoperative condition of surrounding soft tissue. That specificity prevents downcoding to an unlisted or less-complex bone excision code and gives auditors the operative detail needed to defend the 90-day global and any same-day procedure billing.

See how Mira captures CPT 25150 documentation