Modifiers · CPT modifier

Unplanned return to OR

Modifier 78 tells a payer that the same provider had to bring a patient back to a fully equipped operating or procedure room—unplanned—for a complication or related issue that arose during the global period of a prior surgery. Because the preoperative and postoperative work were already bundled into the original payment, only the intraoperative portion of the fee is reimbursable for the return visit.

Verified May 8, 2026 · 9 sources ↓

Type: CPT
CPT codes use it: 1,521
Top regions: Foot & ankle, Other, Hand

Drawn from AMACMSNovitas SolutionsAAPCCalifornia Medical

When to use modifier 78

Source · Editorial brief grounded in 9 cited references ↓

Append modifier 78 when three conditions are all true at the same time: (1) the patient developed a complication or related problem during the active global period (10-day or 90-day) of a surgery you already performed; (2) treating that complication required a formal return to an operating room, cardiac catheterization suite, laser suite, or endoscopy suite—not a treatment room, recovery bay, or ICU; and (3) the same provider who performed the original procedure is performing the return surgery. Use the diagnosis code that describes the complication itself—wound dehiscence, post-op hematoma, hardware failure—not the diagnosis that drove the original case.

Modifier 78 is the correct choice when the return trip is unplanned and the new procedure is causally related to the first surgery. It is not the right modifier when the second procedure was already anticipated at the time of the first surgery (that is modifier 58), nor when the second procedure is entirely unrelated to the first (that is modifier 79). A new global period does NOT start when modifier 78 is used; the clock continues running from the original surgery date.

Do not append modifier 78 to procedure codes carrying a global-period indicator of 000, XXX, or ZZZ. It applies exclusively to codes with 010 or 090 global periods. It is also invalid on ASC facility claims and should never be attached to E/M codes.

Orthopedic scenarios

Concrete situations in orthopedic practice that warrant modifier 78.

Source · Editorial brief grounded in AAOS coding guidance and cited references ↓

A patient undergoes total knee arthroplasty (TKA, CPT 27447, 90-day global). On post-op day 6, imaging confirms an acute hemarthrosis requiring irrigation and drainage in the OR. Bill 27310-78 (arthrotomy, knee, for infection/foreign body) with the post-op hemarthrosis diagnosis code—not the original osteoarthritis code.
An ORIF of a distal radius fracture (CPT 25609, 90-day global) is performed. On post-op day 14, hardware prominence causes skin breakdown and the plate must be partially repositioned in the OR. Report the hardware revision code appended with modifier 78 and list the post-operative wound complication as the diagnosis.
A patient has an arthroscopic rotator cuff repair (CPT 29827, 90-day global). On post-op day 21, a knot from the suture anchor erodes through the bursal surface and requires arthroscopic removal under general anesthesia. Append modifier 78 to the appropriate arthroscopic shoulder procedure code and document the suture complication as the indication.
After an ACL reconstruction with patellar tendon autograft (CPT 27407, 90-day global), the patient returns to the OR on post-op day 10 with a confirmed deep wound infection requiring formal irrigation, debridement, and re-closure (CPT 27301). Append modifier 78; bill with the post-operative deep infection diagnosis, not the original ligament rupture code.
A lumbar spinal fusion (CPT 22612, 90-day global) is complicated by a dural tear that was not detected intraoperatively. On post-op day 3, a CSF leak is confirmed and the patient is taken back to the OR for primary dural repair. Report the dural repair code with modifier 78 and cite the post-procedural CSF leak as the diagnosis.

Common mistakes

Where coders most often go wrong with modifier 78.

Source · Editorial brief grounded in CMS NCCI Policy Manual and cited references ↓

Appending modifier 78 to procedure codes with a 000, XXX, or ZZZ global-day indicator—it is only valid on 010 and 090 global-period codes.
Using modifier 78 instead of modifier 58 when the return-to-OR procedure was actually planned or staged at the time of the original surgery.
Applying modifier 78 to a procedure performed in a treatment room, recovery room, or ICU—CMS requires a fully equipped OR or equivalent suite; doing so outside that setting causes claim denial.
Reporting the original diagnosis instead of the complication diagnosis on the modifier 78 claim line, which obscures medical necessity for the return surgery and risks audit scrutiny.
Assuming modifier 78 resets the global period—it does not; follow-up care during the extended period still falls inside the original surgery's global window.
Billing modifier 78 and modifier 79 on the same line for the same return procedure—they are mutually exclusive; pick the one that correctly reflects whether the return surgery was related or unrelated to the original.
Using modifier 78 to distinguish multiple procedures performed during the same original operative session—the global period has not yet started at that point, so neither modifier 78 nor 79 applies.
Expecting full fee-schedule reimbursement—payers reimburse only the intraoperative percentage of the allowed amount, typically resulting in a 15–30% reduction from the full fee-schedule value.

CPT codes that use modifier 78

1,521 orthopedic CPT codes in our reference list this modifier as applicable. Sorted by total RVU.

Source · Derived from per-code modifier guidance in our CPT reference

Showing top 12 of 1,521 by total RVU.

Where modifier 78 shows up

Body regions where this modifier most commonly appears in our orthopedic reference.

Foot & ankle 304 codes
Other 203 codes
Hand 185 codes
Wrist 159 codes

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 9 cited references ↓

01Does using modifier 78 start a new global period?

No. The global period continues running from the original surgery date. All post-op follow-up care is still bundled through that original end date, and no new clock begins with the modifier 78 procedure.

02How much will a payer reimburse when modifier 78 is appended?

Payers reimburse only the intraoperative percentage of the fee-schedule allowance—typically 70–85% of the full allowed amount, resulting in a 15–30% reduction. The pre- and post-operative components are considered already paid through the original global fee.

03Can modifier 78 be used for a procedure performed at the bedside or in the ICU?

Only in a narrow exception: CMS permits an ICU to qualify as an OR substitute when the patient's condition was so critical that transporting them to a formal OR would have posed unacceptable risk. Otherwise, the procedure must occur in a room specifically equipped and staffed for performing surgical procedures.

04What is the key difference between modifier 78 and modifier 58?

Modifier 58 is for a return-to-OR procedure that was planned or staged at the time of the original surgery; modifier 78 is for an unplanned return driven by a complication or related problem. Modifier 58 also resets the global period; modifier 78 does not.

05Which diagnosis code should be reported with a modifier 78 claim?

Report the diagnosis that describes the complication requiring the return surgery—such as post-operative wound dehiscence, hematoma, or infection—not the original condition that prompted the first procedure.

06Is modifier 78 valid on procedure codes with a 000 global-day indicator?

No. Modifier 78 is only valid on procedure codes carrying a 010 or 090 global-period indicator. Codes with 000, XXX, or ZZZ global indicators are billed separately without this modifier.

07Can a different surgeon in the same group practice use modifier 78?

No. The modifier requires the same physician or qualified health care professional who performed the original procedure to also perform the return surgery. If a covering or different surgeon performs the return procedure, modifier 78 does not apply.

08Can modifier 78 and modifier 79 both be appended to the same procedure on the same date?

No. Modifiers 58, 78, and 79 are mutually exclusive. Only one of the three may be appended to a given procedure code for a return surgery occurring within the original global period.

Sources & references

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

01AMA CPT Professional Edition – Appendix A, Modifier 78 descriptor and guidelines
02CMS Medicare Claims Processing Manual, Publication 100-04, Chapter 12, Sections 40.2A and 40.4C
03CMS 2025 NCCI Medicare Coding Policy Manual, Chapter I, Section E – Modifiers and Modifier Indicators (https://www.cms.gov/files/document/2025nccimedicarepolicymanualcompletepdf.pdf)
04Novitas Solutions Medicare JH Modifier 78 Fact Sheet (https://www.novitas-solutions.com/webcenter/portal/MedicareJH/pagebyid?contentId=00144546)
05AAPC Orthopedic Coding Alert – Modifiers: Follow These Dos and Don'ts of Using Modifier 78 (https://www.aapc.com/codes/coding-newsletters/my-orthopedic-coding-alert/modifiers-follow-these-dos-and-donts-of-using-modifier-78-154844-article)
06AAPC Knowledge Center – When to Use Post-Op Modifiers 58, 78, 79 (https://www.aapc.com/blog/24234-choose-which-modifier-58-78-or-79/)
07California Medical Association CPR Coding Corner – Modifier 78: The Complications Modifier (https://www.cmadocs.org/newsroom/news/view/ArticleId/26757/Coding-Corner-Modifier-78-the-complications-modifier)
08EmblemHealth Global Surgery Reimbursement Policy – Modifier 78 20% Fee Reduction (https://www.emblemhealth.com/providers/claims-corner/coding/global-surgery-reimbursement-policy-concerning)
09Moda Health Reimbursement Policy RPM010 – Modifiers 58, 78, and 79: Staged, Related, and Unrelated Procedures (https://www.modahealth.com/-/media/modahealth/shared/Provider/Policies/RPM010.pdf)

Mira AI Scribe

When documenting a return to the OR during an active global period, the operative note must clearly establish three facts for modifier 78 to be defensible: (1) the complication or related condition that necessitated the return—describe its onset, clinical findings, and why conservative management was insufficient; (2) confirmation that the procedure took place in a formally equipped operating or procedure room, not a bedside or treatment-room setting; and (3) the identity of the operating surgeon as the same provider who performed the original surgery. The diagnosis assigned to the return surgery should reflect the complication—for example, post-operative hematoma, wound dehiscence, or implant complication—not the diagnosis from the index procedure. Avoid language suggesting the return was planned or anticipated at the time of the original surgery, which would shift the correct modifier to 58. A brief timeline noting the original surgery date and the return-to-OR date strengthens the record and confirms the procedure occurred within the applicable global window.

See how Mira flags modifier 78 in dictation