Surgical opening of a metatarsophalangeal joint for exploration, drainage of infection or fluid, or removal of a loose or foreign body.

Verified May 8, 2026 · 6 sources ↓

Medicare: $497.67
Work RVU: 4.69
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 6 cited references ↓

Specify the exact MTP joint involved (e.g., first MTP right, third MTP left) — 'foot joint' alone is insufficient.
Document the surgical indication: infection with purulence, loose body, foreign body, or other pathology prompting open exploration.
Describe operative findings in detail: appearance of synovium, cartilage, presence and character of fluid, any material removed.
Record the approach, joint entry technique, and closure method — notes that only say 'standard approach' are audit targets.
If modifier 22 is appended, the note must quantify the additional work (e.g., dense adhesions, anatomic distortion from prior surgery) and document increased time or complexity.
Confirm laterality is documented in both the pre-op diagnosis and the operative note to support LT or RT modifier.

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 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

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 28022 covers an arthrotomy of the metatarsophalangeal (MTP) joint — the joint where a metatarsal meets a toe — performed to explore the joint space, drain purulent fluid or hematoma, or retrieve a loose body or foreign material. The surgeon opens the joint capsule under sterile OR conditions, inspects the articular surfaces and synovium, addresses the pathology found, and closes in layers. This is a distinct open procedure; it is not an incision-and-drainage of soft tissue and should not be confused with codes for tendon or bone work performed at the same site.

The 90-day global period means the surgery, the day-before visit, and all routine postoperative management through day 90 are bundled. Any same-day E/M for a separate, unrelated problem requires modifier 25. A return to the OR for a complication related to the original procedure bills with modifier 78; an unrelated return to the OR in the global window uses modifier 79.

Laterality modifiers (LT/RT) are expected by most payers. If both feet are operated on in the same session, append modifier 50 and confirm the payer's bilateral payment policy before submitting — many apply a 150% rule rather than paying two full fees.

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 (4.69) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (14.9) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.69
Practice expense RVU	9.66
Malpractice RVU	0.55
Total RVU	14.9
Medicare national rate	$497.67
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	$497.67
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 28022 get rejected.

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

Missing laterality modifier — most payers auto-deny 28022 without LT or RT on claims for a unilateral procedure.
Bundling with same-session open bone or soft-tissue procedures at the same MTP joint without modifier 59 to establish a distinct service.
Medical necessity not supported when the diagnosis code reflects a chronic degenerative condition rather than acute infection, foreign body, or loose body requiring open exploration.
Global period conflict — billing a related E/M or minor procedure within the 90-day global without the correct modifier (24 or 79).
Upcoding flag when the operative note describes only a soft-tissue I&D rather than true arthrotomy with joint entry and inspection.

Frequently asked questions

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

01When does an MTP joint infection warrant 28022 rather than a soft-tissue I&D code?

Use 28022 when the surgeon enters the joint capsule and inspects the articular space. If the incision and drainage stays in periarticular soft tissue without penetrating the capsule, a soft-tissue I&D code is more accurate. The operative note must confirm joint entry.

02Can 28022 be billed with bunionectomy codes on the same day?

NCCI bundles many accessory procedures into bunionectomy codes. If you're billing 28022 alongside a bunionectomy (e.g., 28296), verify the NCCI PTP edit table — if an edit exists, modifier 59 requires clear documentation that the arthrotomy was a distinct service at a separate joint or for a separate indication.

03How do you handle billing when both first MTP joints are explored in the same session?

Append modifier 50 to 28022 and submit as a single line item per most payer instructions, or as two line items with LT and RT depending on the payer. Confirm bilateral payment policy first — many payers pay 150% of the single-procedure allowable, not 200%.

04What modifier applies if the patient returns to the OR within the 90-day global for a new infection in the same joint?

Modifier 78 covers an unplanned return to the OR for a complication related to the original procedure. If the new infection is documented as a distinct, unrelated condition, modifier 79 applies. The distinction lives in the clinical documentation — don't rely on coder judgment alone.

05Is an E/M billable on the same day as 28022?

Only if the E/M addresses a problem unrelated to the MTP joint exploration. Append modifier 25 to the E/M and document the separate medical decision-making in the note. A pre-op assessment for the same condition is not separately billable.

06Does site of service affect reimbursement for 28022?

Yes. HOPD and ASC facility payments differ significantly — see the site of service comparison table on this page. The physician professional fee is also subject to the site-of-service differential under the CMS Physician Fee Schedule 2026; the non-facility RVU is higher than the facility RVU.

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 MTP joint treated, laterality, the operative indication (septic joint, loose body, foreign body), intraoperative findings including synovial and cartilage appearance, volume and character of any fluid drained, material removed, and closure technique — all from dictation. That structured capture prevents the two most common denial triggers: missing laterality and an operative note too vague to justify open arthrotomy over soft-tissue I&D.

See how Mira captures CPT 28022 documentation