Surgical lengthening of both the radius and ulna using bone graft harvested from the patient (autograft), performed to correct forearm length discrepancy or deformity.

Verified May 8, 2026 · 6 sources ↓

Medicare: $1,033.09
Total RVUs: 30.93
Global, days: 90
Region: Wrist

Drawn from CMSEmednyGenhealthAAPC

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Diagnosis specifying forearm length discrepancy, deformity, or other indication requiring bilateral bone lengthening
Operative note confirming osteotomy of both radius AND ulna — single-bone procedures do not support 25393
Autograft harvest site documented by name (e.g., iliac crest, distal radius), including graft dimensions and volume
Fixation method and implant details (plate, intramedullary device, external fixator) recorded in the operative note
Pre- and post-operative imaging (plain films or fluoroscopy) confirming deformity and correction
Failure of conservative management or documented clinical necessity for surgical intervention

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 52 Reduced services 58 Staged or related 59 Distinct service 62 Co-surgeons 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 25393 covers osteoplasty of both the radius and ulna with lengthening via autograft. The surgeon cuts through each bone, interposes autogenous bone graft to span the created gap, and stabilizes the construct with fixation. Both bones must be addressed — if only one forearm bone is lengthened, 25391 applies instead. Autograft harvest is included in the code and not separately billable.

This is a 90-day global procedure. All routine follow-up, dressing changes, and cast management through day 90 are bundled. Unrelated E/M visits in that window require modifier 24; a significant, separately identifiable E/M on the day of surgery requires modifier 25. A planned staged procedure during the global period bills with modifier 58; an unplanned return for a related complication uses modifier 78.

The procedure falls under Repair, Revision, and/or Reconstruction of the Forearm and Wrist. It is billed primarily by hand surgeons. Site of service matters — HOPD and ASC facility payments differ substantially (see the Site of Service comparison table on this page). Document the indication, the specific osteotomy technique, graft harvest site, volume and dimensions of graft used, fixation method, and intraoperative fluoroscopy findings to support medical necessity and withstand audit.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	16.15
Practice expense RVU	11.34
Malpractice RVU	3.44
Total RVU	30.93
Medicare national rate	$1,033.09
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	$1,033.09
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,727.17

Common denial reasons

The recurring reasons claims for CPT 25393 get rejected.

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

Code billed when only one forearm bone was lengthened — use 25391 for radius OR ulna alone
Autograft harvest billed separately when it is already bundled into 25393
Medical necessity not established — absence of imaging or clinical documentation quantifying length discrepancy
ICD-10 diagnosis code does not map to a bilateral forearm deformity or length discrepancy
Missing operative detail on graft harvest site or fixation, triggering post-payment audit recoupment

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What is the difference between 25393 and 25391?

25391 covers lengthening of the radius OR ulna (one bone) with autograft. 25393 requires lengthening of both the radius AND ulna in the same operative session. If only one bone was cut and lengthened, 25393 does not apply.

02Is autograft harvest separately billable with 25393?

No. Autograft harvest is included in 25393. Billing a separate graft harvest code alongside this procedure will be denied as unbundling.

03Can 25393 be billed bilaterally (both arms)?

If both forearms are operated on at the same session, append modifier 50 for a bilateral procedure, or use LT and RT on separate claim lines per payer preference. Confirm payer-specific bilateral billing rules before submitting — some require separate lines, others accept modifier 50 on a single line.

04How does the 90-day global period affect post-op billing?

Routine post-op visits, dressings, cast checks, and stitch removal through day 90 are bundled. Bill unrelated conditions with modifier 24 on E/M codes. Use modifier 58 for a planned staged procedure within the global, and modifier 78 for an unplanned return to the OR for a related complication.

05What ICD-10 codes typically support 25393?

Common supporting diagnoses include congenital forearm deformities (Q71-series), acquired deformity of the forearm (M21.83x), malunion of radius and ulna fractures (M84.33x), and sequelae of prior forearm fractures. The diagnosis must reflect a bilateral forearm condition to support the AND code.

06When should modifier 22 be used with 25393?

Append modifier 22 when the procedure required substantially increased work beyond what the code typically represents — for example, severe scarring from prior surgery, complex deformity requiring intraoperative problem-solving, or significantly prolonged operative time. Document the specific factors increasing complexity in the operative note; payers will request records before paying the upcharge.

Sources & references

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

Mira AI Scribe

Mira's AI scribe captures from dictation: osteotomy technique for both radius and ulna, graft harvest site and dimensions, fixation construct, and fluoroscopic confirmation of alignment. This prevents the most common audit flag — operative notes that confirm only one bone was addressed or that omit autograft harvest detail, which auditors use to downcode to 25391 or deny the graft-inclusive bundling entirely.

See how Mira captures CPT 25393 documentation