Arthroscopic surgical removal of the entire synovial lining of the wrist joint (complete synovectomy) performed through small portals with a scope and instruments.

Verified May 8, 2026 · 7 sources ↓

Medicare: $546.77
Total RVUs: 16.37
Global, days: 90
Region: Wrist

Drawn from CMSAAPCUhcproviderFastrvuEatonhand

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Specify complete vs. partial synovectomy — documentation must support complete removal to justify 29845 over 29844
Name the underlying diagnosis driving synovectomy (e.g., rheumatoid arthritis, PVNS, crystalline arthropathy) with supporting ICD-10 code
Document portal placement sites and confirm arthroscopic approach was maintained throughout; note if conversion to open occurred
Record the extent of synovial involvement visualized and confirm all compartments addressed for 'complete' characterization
Note any concomitant procedures performed (e.g., loose body removal, TFCC assessment) and whether they were separately reportable or integral to the primary procedure
Laterality must be explicit — right, left, or bilateral — in both the operative note and the claim

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 50 Bilateral procedure 51 Multiple procedures 59 Distinct service 76 Repeat, same physician 77 Repeat, another physician 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 29845 describes a complete arthroscopic synovectomy of the wrist — the surgeon removes the entire inflamed or diseased synovial membrane from the wrist joint using arthroscopic technique. This distinguishes it from 29844 (partial synovectomy), where only the most affected tissue is excised. The procedure is indicated for conditions such as rheumatoid arthritis, pigmented villonodular synovitis (PVNS), or other inflammatory synovial disorders that haven't responded to conservative management.

The 90-day global period means all routine post-op visits, wound checks, and splint/cast management through day 90 are bundled — bill those separately only with modifier 24. Per NCCI policy, the surgical arthroscopy includes the diagnostic evaluation; don't report 29840 alongside 29845 for the same session. Standard access, joint irrigation, and any limited debridement performed purely to visualize the field are also bundled and cannot be billed separately.

If the arthroscopy is converted to an open wrist synovectomy (CPT 25105), report only the open procedure. Reporting both the attempted arthroscopy and the open code is unbundling under NCCI rules. When bilateral wrists are addressed in the same session — uncommon but seen in systemic inflammatory disease — append modifier 50.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	7.5
Practice expense RVU	7.42
Malpractice RVU	1.45
Total RVU	16.37
Medicare national rate	$546.77
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	$546.77
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 29845 get rejected.

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

29844 (partial) billed as 29845 (complete) without operative note confirming full synovial membrane removal — payers downcode on review
Diagnostic arthroscopy 29840 billed same-session alongside 29845 — surgical arthroscopy includes the diagnostic component under NCCI bundling rules
Missing or inadequate documentation of medical necessity for complete synovectomy, especially when conservative treatment history is not captured in the record
Laterality modifier absent (LT or RT) triggering claim suspension or rejection under payers requiring explicit side designation
Concomitant debridement or irrigation billed separately when performed as an integral step to access or visualize the joint during the primary synovectomy

Frequently asked questions

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

01What separates 29845 from 29844?

29844 is a partial synovectomy — the surgeon removes only the most involved synovial tissue. 29845 is complete, meaning the entire synovial lining of the wrist joint is excised. Your operative note must reflect complete removal across all affected compartments or the payer will downcode to 29844 on audit.

02Can I bill 29840 alongside 29845 when diagnostic arthroscopy precedes the synovectomy in the same session?

No. NCCI policy bundles the diagnostic evaluation into the surgical arthroscopy. Report only 29845. The only scenario where 29840 is separately reportable is when a diagnostic arthroscopy is performed, findings are noted, and the surgeon then decides to perform a separate open procedure — not an arthroscopic one — at that same session.

03If the arthroscopy is converted to an open synovectomy (25105), what do I bill?

Bill only the open procedure code (25105). Reporting 29845 for the attempted arthroscopy plus 25105 for the completed open procedure is unbundling under NCCI. Document the conversion and reason in the operative note.

04What modifier applies if the patient returns to the OR within the 90-day global for a related wrist procedure?

Modifier 78. That signals an unplanned return to the OR for a procedure related to the original surgery within the global period. If the return procedure is unrelated to the wrist synovectomy, use modifier 79 instead. Do not invert these — 78 is related, 79 is unrelated.

05Is 29845 ever billed bilaterally, and how?

Bilateral wrist synovectomy in one session is uncommon but occurs in systemic inflammatory disease (e.g., RA). Append modifier 50 to 29845 on a single line, or bill two lines with LT and RT per payer preference. Confirm the operative note documents both wrists were fully addressed.

06Can I separately bill debridement performed during the same wrist arthroscopy session?

Only if the debridement is a distinct surgical service, not merely access or visualization work. NCCI policy bundles debridement that is integral to performing the primary arthroscopic procedure. If a separately identifiable and medically necessary debridement is performed, modifier 59 may apply — but the operative note must clearly support the distinction.

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 surgeon's dictation for key 29845 billing elements: confirmation that synovectomy was complete (all compartments), the specific synovial pathology encountered, portal sites used, laterality, and whether any conversion to open technique occurred. This prevents the most common audit flag — operative notes that say 'synovectomy performed' without specifying complete vs. partial extent, which gives payers grounds to downcode to 29844.

See how Mira captures CPT 29845 documentation