Surgical freeing of adhesions around a single flexor tendon in the foot to restore gliding motion and relieve pain.

Verified May 8, 2026 · 6 sources ↓

Medicare: $446.57
Work RVU: 4.55
Global, days: 90
Region: Foot & ankle

Drawn from CMSAAPCRedditMdclarity

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Identify the specific tendon by name (e.g., flexor hallucis longus, flexor digitorum longus) — generic references to 'foot tendon' invite downcoding
Confirm the tendon type is flexor, not extensor; extensor tenolysis maps to 28225/28226
State whether one or multiple tendons were released; multiple flexor tendons shift the code to 28222
Document clinical indication: adhesion formation, post-traumatic or post-surgical scarring, restricted tendon excursion with functional deficit
Record pre-op range-of-motion or tendon glide assessment to establish medical necessity
If bilateral, document each side separately and note whether the contralateral foot was treated in the same operative session

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 50 Bilateral procedure 51 Multiple procedures 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 6 cited references ↓

CPT 28220 covers tenolysis of a single flexor tendon in the foot — the surgical division of adhesions or scar tissue binding the tendon so it can glide freely. It is distinct from extensor tenolysis (28225) and from the multiple-tendon flexor variant (28222). Choosing the wrong code in this family is a top audit trigger; the operative note must specify flexor vs. extensor and single vs. multiple tendons.

The 90-day global period means all routine post-op visits, wound care, and related follow-up through day 90 are bundled. Anything unrelated billed in that window needs modifier 24 (E/M) or 79 (unrelated procedure). If a related complication requires a return to the OR, append modifier 78. Medicare's MUE for 28220 is 1 unit per day with a Medically Unlikely Edit adjudication indicator of 2 — billing more than one unit on the same date will deny without documented extraordinary circumstances.

Site of service matters significantly here: HOPD and ASC facility payments differ substantially (see the Site of Service comparison table). Most volume runs through podiatry, though orthopedic foot-and-ankle specialists bill it as well. Bilateral cases should follow payer-specific instructions — some require two line items with LT/RT, others want a single line with 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 vs. total RVU

The work RVU (4.55) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (13.37) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.55
Practice expense RVU	8.38
Malpractice RVU	0.44
Total RVU	13.37
Medicare national rate	$446.57
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	$446.57
HOPD (APC 5112) Hospital outpatient department	$1,642.82
ASC (PI P3) Ambulatory surgical center (freestanding)	$281.63

Common denial reasons

The recurring reasons claims for CPT 28220 get rejected.

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

MUE exceeded — Medicare will not pay more than 1 unit of 28220 per day without additional documentation supporting medical necessity
Wrong code family — operative note describes extensor tendon release but 28220 (flexor) was billed
Bundling conflict when billed same-day with a primary foot reconstruction without modifier 59 or XS to establish distinct procedural service
Missing or vague tendon identification in the operative note; audit teams reject claims that reference only 'adhesion release' without naming the tendon
Post-op period billing error — follow-up E/M visits submitted without modifier 24 during the 90-day global window

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What is the difference between 28220 and 28222?

28220 is for a single flexor tendon; 28222 applies when two or more flexor tendons are released in the same foot during the same session. The operative note must specify how many tendons were addressed.

02Can 28220 and 28225 be billed together on the same foot?

Yes, if both a flexor and an extensor tendon were released on the same foot in the same session. Append modifier 51 to the lower-valued code and document each tendon distinctly in the operative note.

03How should bilateral foot tenolysis be billed?

Payer rules differ. Most commercial payers and Medicare accept either two line items with LT on one and RT on the other, or a single line with modifier 50. Confirm with the specific payer before submitting — some will reject the 50 approach and require separate lines.

04What diagnoses support medical necessity for 28220?

Common supporting ICD-10 codes include tendinous adhesions post-injury or post-surgery, stenosing tenosynovitis of the foot, and flexor tendon contracture. The diagnosis must align with documented functional limitation and failure of conservative management.

05Does the 90-day global period apply to 28220?

Yes. The global period is 90 days. Routine post-op visits, dressing changes, and suture removal are bundled. Bill unrelated E/M services with modifier 24 and unrelated procedures with modifier 79. A related return to the OR requires modifier 78.

06Why is the ASC reimbursement for 28220 much lower than HOPD?

CMS sets HOPD rates under the Outpatient Prospective Payment System and ASC rates under a separate fee schedule, which historically reimburses facility services at a lower rate for lower-acuity procedures. The gap for 28220 is substantial — see the Site of Service comparison table on this page for 2026 figures.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the tendon name, compartment (flexor vs. extensor), laterality, and the number of tendons released directly from dictation. It also flags when the operative note uses generic language like 'adhesion release' without identifying the specific structure — the exact gap that triggers audits and medical-necessity denials. For bilateral cases, laterality is tagged automatically so the correct modifier (LT/RT or 50) populates before the claim goes out.

See how Mira captures CPT 28220 documentation