Secondary closure of a shoulder disarticulation wound, performed as a staged procedure after the initial amputation.
Verified May 8, 2026 · 5 sources ↓
- Medicare
- $459.26
- Work RVU
- 5.58
- Global, days
- 90
- Region
- Shoulder
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 5 cited references ↓
- Operative note from the initial disarticulation (23900) documenting why primary closure was deferred
- Interim wound care records between the disarticulation and secondary closure, including wound condition and any infection management
- Operative note for 23921 describing wound bed status at time of closure, closure technique, and tissue layers involved
- Medical necessity narrative explaining the clinical indication for staged rather than primary closure
- Identification of surgeon and facility for both the index procedure and secondary closure, especially if different providers
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 5 cited references ↓
CPT 23921 covers the secondary closure of a shoulder disarticulation site — meaning the surgeon returns to close a wound that was intentionally left open after the primary amputation (23900). This staged approach is standard when infection, contamination, or soft-tissue viability concerns prevent primary closure at the time of disarticulation.
The 90-day global period governs this code. Because 23921 is itself a staged or related procedure following 23900, it typically falls within the global of the index surgery. Bill it with modifier 58 when returning to the OR for this planned second stage during the global period of 23900. If the closure is for an unrelated reason or a different surgeon performs it, apply modifier 79 or 62 accordingly.
Not a high-volume code — it surfaces primarily in trauma, oncologic, or severe infection cases. Payer scrutiny focuses on whether the open wound management between the disarticulation and this closure was medically necessary and well-documented. Operative notes for both encounters need to tell a coherent clinical story: why the wound was left open, what interim wound care occurred, and why closure is appropriate now.
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 (5.58) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (13.75) adds practice overhead and malpractice, and is what drives the Medicare payment below.
| Work RVU | 5.58 |
| Practice expense RVU | 6.97 |
| Malpractice RVU | 1.2 |
| Total RVU | 13.75 |
| Medicare national rate | $459.26 |
| 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 | $459.26 |
HOPD (APC 5054) Hospital outpatient department | $2,107.97 |
ASC (PI A2) Ambulatory surgical center (freestanding) | $1,128.57 |
Common denial reasons
The recurring reasons claims for CPT 23921 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Bundling into the global period of 23900 without modifier 58 to establish the staged/planned nature of the return
- Missing documentation linking this closure to the original disarticulation, causing payer to treat it as an unrelated wound closure billed without adequate support
- Lack of interim wound care records making medical necessity for delayed closure unsubstantiated
- Incorrect modifier 78 applied instead of modifier 58 — 78 is for unplanned returns for related procedures, not planned staged closures
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 5 cited references ↓
01Is 23921 billed during the global period of 23900, and which modifier applies?
02What if a different surgeon performs the secondary closure than the one who did the disarticulation?
03Can wound debridement codes be billed separately alongside 23921?
04What documentation justifies leaving the wound open after the initial disarticulation?
05Does SNF consolidated billing affect 23921?
06Is modifier 22 ever appropriate for 23921?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CMS Physician Fee Schedule 2026
- 02bedrockbilling.comhttps://bedrockbilling.com/static/cci/23921
- 03cms.govhttps://www.cms.gov/medicare/regulations-guidance/physician-self-referral/list-cpt-hcpcs-codes
- 04cms.govhttps://www.cms.gov/files/document/r12052cp.pdf
- 05emedny.orghttps://www.emedny.org/providermanuals/physician/pdfs/physician%20procedure%20codes%20sect5.pdf
Mira Scribe
Mira's AI scribe captures the wound condition at time of closure, the closure technique and tissue layers approximated, the reason primary closure was deferred at initial disarticulation, and any interval wound care performed. This prevents denials driven by missing clinical continuity between 23900 and 23921 — the two most common audit flags on staged amputation closures.
See how Mira captures CPT 23921 documentation