Surgical removal of inflamed or diseased synovial tissue from the flexor tendon sheath of the foot to relieve pain and restore function.

Verified May 8, 2026 · 7 sources ↓

Medicare: $540.43
Work RVU: 4.8
Global, days: 90
Region: Foot & ankle

Drawn from CMSAAPCGenhealthFindacodeMdclarity

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Specify which flexor tendon sheath(s) were involved and their anatomic location on the foot
Document failed conservative treatment prior to surgery (duration, modalities attempted)
Operative note must name the specific incision site and confirm synovial tissue was excised, not just debrided
If multiple sheaths treated, document each as anatomically distinct with separate incisions
Record pre-op diagnosis (e.g., chronic flexor tenosynovitis, rheumatoid synovitis) with supporting ICD-10 code
Note whether concurrent tendon pathology was addressed and on which tendon, to support or rebut bundling with repair codes

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 25 Significant separate E/M 50 Bilateral procedure 51 Multiple procedures 58 Staged or related 59 Distinct service 76 Repeat, same physician 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 7 cited references ↓

CPT 28086 describes a flexor tendon sheath synovectomy of the foot — an open procedure in which the surgeon excises hypertrophic or inflamed synovial tissue from the tendon sheath. Indications include chronic synovitis that has failed conservative management, rheumatoid arthritis-related synovial hypertrophy, or mechanical symptoms from synovial nodules. The surgeon incises the skin over the affected flexor tendon, opens the sheath, and removes diseased synovium before closing in layers.

This code carries a 90-day global period, meaning all routine post-op visits, wound checks, and suture removal through day 90 are bundled. Any unrelated E/M service in that window requires modifier 24; a significant, separately identifiable E/M on the day of surgery requires modifier 25. When synovectomy is performed on the same tendon as a tendon repair (e.g., 28200), NCCI edits typically bundle 28086 into the repair — do not report both without confirming a distinct, separate site justifies modifier 59 or XS.

Billing the code once per sheath is the correct approach even when multiple tendons run through a single sheath. If the surgeon documents work in anatomically separate sheaths on the same foot, a second unit with modifier 59 or XS and supporting operative detail may be defensible — but the default is one unit per distinct sheath, not per tendon.

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 (4.8) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (16.18) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.8
Practice expense RVU	10.73
Malpractice RVU	0.65
Total RVU	16.18
Medicare national rate	$540.43
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	$540.43
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 28086 get rejected.

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

Bundling with same-session tendon repair (28200) when both procedures address the same tendon — NCCI edit applies
Bilateral procedure billed without modifier 50 or without separate LT/RT line items per payer preference
Lack of documentation showing conservative treatment failure, triggering medical necessity denial
Operative note describes debridement language only rather than excision of synovium, causing downcoding or denial
Global period violation — post-op E/M billed without modifier 24 during the 90-day window

Frequently asked questions

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

01Does 28086 bundle with 28200 (flexor tendon repair) when both are done at the same session?

Yes, when both procedures address the same tendon, NCCI edits bundle the synovectomy into the repair. If the synovectomy was performed at a genuinely separate site or separate sheath, append modifier 59 or XS and document the distinct anatomy explicitly in the operative note.

02Can 28086 be billed twice if the surgeon works on two tendons inside the same sheath?

No. The code is per sheath, not per tendon. Multiple tendons within a single sheath do not justify a second unit. If the surgeon treated two anatomically separate sheaths through separate incisions, a second unit with modifier 59 or XS and clear operative documentation may be supported.

03What modifier applies when 28086 is done bilaterally in the same session?

Use modifier 50 for Medicare and payers that accept a single line with modifier 50. Some commercial payers prefer two lines with LT and RT. Confirm the payer's bilateral billing preference before submitting.

04What global period applies to 28086, and what does that cover?

28086 carries a 90-day global. That includes the day of surgery, the day-before pre-op visit, and all routine post-op care through day 90. Unrelated E/M services in that window need modifier 24; a distinct E/M on the day of surgery needs modifier 25.

05Which ICD-10 codes most commonly support medical necessity for 28086?

M65.871 and M65.872 (other synovitis and tenosynovitis, foot and ankle) are the most common. Rheumatoid arthritis with foot involvement (M05.x7x, M06.x7x) also supports the procedure. Payers expect documentation of prior conservative management failure before approving surgical synovectomy.

06Is 28086 typically performed in an ASC or hospital outpatient setting?

Both settings are used. The procedure is well-suited for ASC given its outpatient nature. Site-of-service differences affect facility payment rates — see the Site of Service comparison table for HOPD versus ASC payment figures under CMS Physician Fee Schedule 2026.

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 flexor tendon sheath location, the description of synovial tissue removed (volume, character, extent), confirmation of a distinct incision site, and any concurrent tendon pathology addressed. That detail prevents bundling denials when 28086 is billed alongside a repair code and supports medical necessity if a payer audits for conservative-treatment failure documentation.

See how Mira captures CPT 28086 documentation