Prophylactic reinforcement of the clavicle using internal fixation hardware or bone cement to prevent pathological fracture.

Verified May 8, 2026 · 7 sources ↓

Medicare: $800.62
Total RVUs: 23.97
Global, days: 90
Region: Shoulder

Drawn from CMSAAPCHealthDamManuals

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Preoperative imaging (X-ray, CT, or MRI) documenting the structural defect, lesion, or tumor involvement in the clavicle
Operative note specifying the type and brand of fixation hardware used (nail, plate, screws) and/or use of methylmethacrylate bone cement
Pathology or oncology records if the indication is metastatic disease or primary bone tumor — justifies medical necessity for prophylactic fixation
Explicit statement in the op note that the procedure was prophylactic (fracture not yet present) and why structural failure was imminent without intervention
Laterality documented — left or right clavicle — to support LT or RT modifier use
If modifier 22 is appended, a separate written justification with time and complexity detail beyond the standard procedure

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 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

CPT 23490 covers open surgical reinforcement of the clavicle — the collarbone — typically performed when the bone is at risk of pathological fracture due to metastatic disease, primary bone tumor, cyst, or other structural compromise. The surgeon stabilizes the weakened segment using fixation implants such as intramedullary nails, plates, or screws. Bone cement (methylmethacrylate) may also be packed into the defect for additional structural support. This is a prophylactic procedure: the fracture has not yet occurred, but the bone cannot sustain normal loads without intervention.

The 90-day global period means all routine post-op care — wound checks, implant monitoring visits, dressing changes — is bundled through day 90. Any visit for an unrelated problem during that window needs modifier 24 on the E/M. If a complication requires a return to the OR for a related procedure, bill the return with modifier 78. An unrelated surgical problem addressed in a separate OR visit during the global gets modifier 79.

Don't confuse 23490 with neighboring codes. Code 23480 and 23485 are osteotomies of the clavicle — cutting and repositioning, not reinforcing. Code 23491 is the companion code for prophylactic reinforcement of the proximal humerus or scapula, not the clavicle. Billing 23490 when the operative note describes a clavicle osteotomy, or vice versa, is one of the more common upcoding flags on 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	11.86
Practice expense RVU	9.58
Malpractice RVU	2.53
Total RVU	23.97
Medicare national rate	$800.62
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	$800.62
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI A2) Ambulatory surgical center (freestanding)	$3,695.53

Common denial reasons

The recurring reasons claims for CPT 23490 get rejected.

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

Medical necessity not established — payer requires documented imaging and oncology or orthopedic rationale showing impending fracture risk before authorizing prophylactic fixation
Wrong code selected — operative note actually describes osteotomy or fracture fixation, which maps to 23480, 23485, or 23515, not prophylactic reinforcement
Missing laterality modifier — many payers and state Medicaid programs require LT or RT on shoulder procedure claims and reject without it
Global period conflict — post-op visit billed without modifier 24 during the 90-day global, triggering automatic bundling denial
Authorization gap — given the HOPD and ASC payment levels, most payers require prior authorization; missing or mismatched auth number is a top denial driver

Frequently asked questions

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

01What is the difference between CPT 23490 and 23485?

23485 is an osteotomy — the surgeon cuts and repositions the clavicle to correct deformity or malunion. 23490 is prophylactic reinforcement — the bone is not cut; it is stabilized with hardware or cement to prevent a pathological fracture. The operative intent and technique are completely different. Using 23485 for a reinforcement procedure is an audit risk.

02When is 23491 billed instead of, or alongside, 23490?

23491 covers prophylactic reinforcement of the proximal humerus or scapula. If the surgeon reinforces only the clavicle, bill 23490 alone. If both the clavicle and another shoulder bone are reinforced in the same session, you may bill both codes with modifier 51 on the secondary procedure. Document each bone and its fixation construct separately in the op note.

03Does 23490 require prior authorization?

Most commercial payers and Medicare Advantage plans require prior authorization given the procedure's acuity and payment level. Confirm authorization before scheduling and ensure the auth number matches the submitted CPT and laterality exactly. A mismatch between authorized code and billed code is a denial source independent of medical necessity.

04What modifier covers a post-op E/M visit during the 90-day global for an unrelated problem?

Use modifier 24 on the E/M code. The visit must address a condition clearly unrelated to the clavicle reinforcement. Document why the visit was unrelated — same-specialty visits during a global period are presumed bundled without a distinct diagnosis and explicit statement of unrelatedness.

05Can 23490 be performed in an ASC setting?

Yes. The code appears on ASC-approved procedure lists, including New York State's APG ambulatory surgery list and TRICARE's approved ASC schedule. The ASC facility payment is significantly lower than the HOPD rate — see the site of service comparison table on this page. Factor that differential into site-of-service decisions when patients have cost-sharing obligations.

06How should fluoroscopy used during clavicle reinforcement be billed?

If fluoroscopic guidance is integral to the fixation procedure — used to confirm hardware placement — it is generally bundled under NCCI policy and should not be reported separately. Only bill a fluoroscopy code separately if it was used for a distinct, separately documented procedure at a different anatomic site during the same encounter.

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 specific indication (metastatic lesion, bone cyst, tumor involvement), the fixation construct used (nail, plate, screws, methylmethacrylate), laterality, and the surgeon's explicit statement that the procedure was performed prophylactically prior to fracture. This prevents the most common audit flag — an op note that describes hardware placement without distinguishing prophylactic reinforcement from fracture fixation, which can trigger a code-level downgrade to 23515 or 23480 on review.

See how Mira captures CPT 23490 documentation