Synovectomy of a single extensor tendon sheath compartment at the wrist, removing inflamed or thickened synovial tissue to restore tendon gliding.

Verified May 8, 2026 · 8 sources ↓

Medicare: $369.75
Work RVU: 4.4
Global, days: 90
Region: Wrist

Drawn from CMSFindacodeAAPCMdclarityPabau

Documentation requirements

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

Source · Editorial brief grounded in 8 cited references ↓

Identify the specific extensor compartment(s) by number or name — e.g., second or fourth dorsal compartment — not just 'extensor tendon sheath'
Describe the synovial pathology observed: degree of inflammation, hypertrophy, or fibrosis, and its impact on tendon function
Confirm single-compartment scope or document each compartment addressed if billing reflects expanded work
Operative note must distinguish synovectomy from incidental tenosynovectomy when performed alongside ganglion excision (25111) to support separate reporting with modifier 59 or XS
Record preoperative diagnosis with supporting ICD-10 code (e.g., M65.831 for right wrist tenosynovitis) linked to medical necessity
Document that conservative measures were attempted or contraindicated prior to surgical intervention

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 52 Reduced services 58 Staged or related 59 Distinct service 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side XS Separate structure

What this code covers

Source · Editorial summary grounded in 8 cited references ↓

CPT 25118 covers excision of the synovial lining from one extensor tendon sheath compartment at the wrist. The surgeon opens the compartment, strips the pathological synovium from around the extensor tendon, and closes. This is a single-compartment procedure — if multiple extensor compartments are involved, documentation must clearly support that scope. The code is most often driven by inflammatory tenosynovitis (e.g., rheumatoid, reactive, or idiopathic), and the operative note must name the specific compartment treated.

A critical bundling issue: when 25118 is performed at the same time as ganglion cyst excision (25111), CCI edits bundle 25118 into 25111 because the ganglion excision is considered the more definitive procedure and tenosynovectomy is its included service. Separately reporting 25118 with 25111 requires modifier 59 (or XS) backed by documentation of extensive, independently pathological synovitis — not just incidental synovitis at the ganglion stalk. Payers and auditors apply this rule strictly.

The 90-day global period means all routine post-op wrist visits, wound checks, and splint management through day 90 are bundled. Any unrelated procedure performed during that window needs modifier 79. A related unplanned return to the OR uses modifier 78. Surgeons billing a staged or planned additional procedure in the global period use modifier 58.

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 (4.4) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (11.07) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.4
Practice expense RVU	5.83
Malpractice RVU	0.84
Total RVU	11.07
Medicare national rate	$369.75
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	$369.75
HOPD (APC 5112) Hospital outpatient department	$1,642.82
ASC (PI A2) Ambulatory surgical center (freestanding)	$872.87

Common denial reasons

The recurring reasons claims for CPT 25118 get rejected.

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

Bundled into concomitant ganglion cyst excision (25111) when documentation doesn't support independent pathological synovitis
Missing compartment-level specificity in the operative note — payers reject notes that reference only 'extensor sheath' without naming the compartment
Laterality not indicated on the claim; LT or RT absent when payer requires it
Services billed during the 90-day global period of a prior wrist procedure without appropriate modifier 24, 78, or 79
ICD-10 diagnosis does not support medical necessity for surgical synovectomy — e.g., a non-inflammatory diagnosis code submitted without supporting clinical rationale

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 8 cited references ↓

01Can I bill 25118 and 25111 together when a ganglion and tenosynovitis are both treated?

Only with strong documentation. CCI edits bundle 25118 into 25111 by default. To separately report both, you need operative documentation showing the synovitis was extensive and independently pathological — not just minor inflammation at the ganglion attachment. Add modifier 59 or XS and a distinct ICD-10 code for the tenosynovitis. Without that, expect denial or downcoding.

02What is the global period for CPT 25118?

90 days. Routine post-op visits, splint adjustments, wound checks, and suture removal within that window are included in the surgical payment. Bill an unrelated procedure in the global with modifier 79; a related unplanned return to the OR uses modifier 78.

03Does 25118 cover multiple extensor compartments if the surgeon treated more than one?

25118 is defined as a single-compartment procedure. If the operative note documents synovectomy across multiple distinct compartments, that scope may support modifier 22 for increased complexity, or your coding team should evaluate whether 25116 (radical excision, extensor sheaths) better fits the work performed.

04Which laterality modifiers are required for 25118?

Use LT for the left wrist and RT for the right. Most payers require laterality on wrist procedures. Omitting it is a common, avoidable denial. If billing bilateral in one session, append modifier 50.

05What ICD-10 codes most commonly link to 25118?

M65.831 (right wrist tenosynovitis), M65.832 (left wrist tenosynovitis), and rheumatoid-related tendon sheath codes under M06 are frequent pairings. The diagnosis must reflect inflammatory or pathological synovial disease — a purely mechanical or post-traumatic note without inflammatory findings may trigger a medical necessity denial.

06Is an assistant surgeon billable with 25118?

Assistant surgeon billing (modifier 80 or AS for a PA/NP) is not routinely payable for 25118 under Medicare. Some commercial payers allow it. Verify payer-specific policy before billing an assistant on this code.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the specific extensor compartment name and number, the surgeon's description of synovial pathology (thickness, extent, inflammatory character), and whether the synovectomy was the primary target or performed alongside another wrist procedure such as ganglion excision. That compartment-level detail prevents downcoding and is the key documentation element auditors check first when 25118 is billed with 25111.

See how Mira captures CPT 25118 documentation