Open surgical treatment of a Monteggia fracture-dislocation at the elbow — fracture of the proximal ulna combined with dislocation of the radial head — including internal fixation when used.

Verified May 8, 2026 · 6 sources ↓

Medicare: $639.96
Total RVUs: 19.16
Global, days: 90
Region: Elbow

Drawn from CMSNIHAAPCFastrvuFindacode

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Confirm both injury components: proximal ulna fracture AND radial head dislocation — both must be documented for 24635 to be defensible
Specify the surgical approach by name and describe layers of dissection to the bone
Document all internal fixation hardware used (plate type, screw count, wire placement) or explicitly note fixation was not performed
Record intraoperative fluoroscopic or imaging confirmation of fracture reduction and joint congruity restoration
Note any ulnar nerve identification, retraction, or intervention — if neuroplasty was performed, document it separately with its own distinct operative narrative
Include pre-op imaging (X-ray or CT) in the record confirming Monteggia pattern to support ICD-10 diagnosis code alignment

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 51 Multiple procedures 58 Staged or related 59 Distinct service 76 Repeat, same physician 77 Repeat, another physician 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 6 cited references ↓

CPT 24635 covers open treatment of a Monteggia injury: a proximal ulna fracture paired with radial head dislocation. The surgeon opens the elbow, reduces the joint, realigns the ulna fracture, and stabilizes the construct with internal fixation (plates, screws, or wires) as needed. Both the fracture reduction and the radiocapitellar joint reduction are bundled into this single code — you do not separately bill for the dislocation reduction.

The 90-day global period applies. All routine post-op visits, dressing changes, and hardware checks through day 90 are included. Use modifier 24 for unrelated E/M services and modifier 79 for an unrelated surgical procedure performed during that window. Modifier 78 covers an unplanned return to the OR for a complication directly tied to the original Monteggia repair — for example, hardware failure requiring revision.

Ulnar nerve neuroplasty or transposition (64718) is a known NCCI column 2 code for 24635 under Medicare. If you performed a distinct ulnar nerve procedure and the patient is on a non-Medicare payer that follows AAOS Global Service Data rather than NCCI edits, verify payer policy before billing 64718 separately. Most commercial payers follow NCCI, so expect denial without strong documentation and a supported modifier.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	8.58
Practice expense RVU	8.84
Malpractice RVU	1.74
Total RVU	19.16
Medicare national rate	$639.96
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	$639.96
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,869.13

Common denial reasons

The recurring reasons claims for CPT 24635 get rejected.

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

ICD-10 diagnosis does not specify Monteggia pattern — generic ulna fracture or elbow dislocation codes without the combined injury classification trigger downcoding
Separate billing of 64718 (ulnar nerve neuroplasty) without modifier when payer follows NCCI PTP edits bundling it into 24635
Missing internal fixation documentation when hardware was used — payers flag notes that reference plates or screws in the dictation but lack specifics
Post-op E/M billed within the 90-day global without modifier 24 or 79, resulting in global period denial
Laterality modifier absent — LT or RT required by most payers; missing laterality triggers claim rejection or manual review hold

Frequently asked questions

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

01Is the radial head dislocation reduction separately billable alongside 24635?

No. Reduction of the radiocapitellar dislocation is bundled into 24635. The code covers both the ulna fracture repair and the joint reduction as a single procedure — billing a separate dislocation code on the same day will trigger an NCCI PTP edit.

02Can I bill 64718 for ulnar nerve transposition done at the same time as 24635?

Not under Medicare — NCCI lists 64718 as a column 2 code for 24635 and bundles it. Some commercial payers following AAOS Global Service Data may allow separate billing with modifier 59 or XS if the nerve work was clearly distinct and separately documented. Verify payer policy before appending a modifier and submitting.

03What modifier applies if I need to return the patient to the OR within 90 days for hardware failure from the original repair?

Use modifier 78 — unplanned return to the OR for a complication related to the original procedure. The second surgery falls within the global period of 24635, and modifier 78 tells the payer this is a related, unplanned return, not a new staged procedure.

04What is the global period for CPT 24635?

90 days. The global covers the day-before visit, the surgery itself, and all routine post-op care through day 90. Unrelated E/M services need modifier 24; unrelated procedures need modifier 79.

05Which ICD-10 codes align with 24635?

Monteggia fracture codes fall under the S52.0– category (fracture of upper end of ulna). The specific code should reflect laterality, displacement status, and encounter type (initial = A for open fracture, subsequent = D or G/K/P depending on healing status). Payers flag claims where a generic ulna fracture ICD-10 is used without the Monteggia pattern specified.

06Does 24635 allow an assistant surgeon?

Yes. Assistant surgeon services can be billed with modifier 80 for an MD assistant or modifier AS for a PA, NP, or CNS assisting at surgery. Verify that your specific payer allows assistant surgeon reimbursement for this code — some payers restrict it based on complexity criteria or teaching hospital status.

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 Monteggia injury pattern from dictation — proximal ulna fracture site, direction of radial head dislocation, approach name, fixation hardware details, and intraoperative reduction confirmation — and flags if either injury component is absent from the note. That prevents the most common denial driver: an ICD-10 or operative note that documents only a ulna fracture or only a dislocation, not the combined Monteggia pattern 24635 requires.

See how Mira captures CPT 24635 documentation