Ask whether the procedure was planned (58), an unplanned related return to the operating room (78) or unrelated (79).
Why it matters in orthopedics
Complications after joint replacement, fracture fixation and spine surgery, such as deep infection, wound dehiscence or hematoma, sometimes require a return to the operating room. Modifier 78 is how the surgeon reports that return trip during the original procedure’s global period. Under Medicare, complications treated without a return to the operating room are part of the global surgical package and are not billed separately.
How it works
Bill the code for the procedure performed on the return trip and add 78. If no code describes it, use the unlisted code in the right series. Use the original surgery’s code only if the identical procedure is repeated (Medicare Claims Processing Manual, Chapter 12, §40.2.A.5).
For Medicare, an operating room is a place specifically equipped and staffed for procedures, including cardiac catheterization, laser and endoscopy suites. It excludes a patient’s room, a minor treatment room, a recovery room and an intensive care unit, unless the patient’s condition is too critical to allow transport to an operating room (§40.1.B).
For a code with a 10- or 90-day global period, Medicare pays the intraoperative portion of the fee schedule amount. A 0-day global code is paid in full. An unlisted code is capped at 50% of the intraoperative value of the original surgery (§40.4.C).
A new postoperative period does not begin (WPS Modifier 78 Fact Sheet).
The CPT definition does not limit 78 to complications, and NCCI allows 78 for control of postoperative bleeding that requires a return to the operating room.
Modifier | When it applies | Payment and global period |
|---|---|---|
Planned or staged, more extensive, or therapy after a diagnostic procedure | Paid separately; new global period | |
Modifier 78 | Unplanned, related return to the operating room | Intraoperative portion; no new global period |
Unrelated procedure | Paid separately; new global period |
Orthopedic example
Two weeks after a left total knee arthroplasty, a 68-year-old patient develops wound drainage, and the same surgeon takes the patient back to the operating room for irrigation and debridement. The practice bills the code for the debridement procedure performed, with modifiers 78 and LT. Medicare pays the intraoperative portion, and the arthroplasty’s original global period keeps running. A clinic wound check or bedside dressing change for the same problem would be included in the global package.
Common denial triggers
78 on a procedure done in the clinic, a minor treatment room or at the bedside.
78 used for a planned, staged procedure (58) or an unrelated one (79).
The original surgery code is reused when a different procedure was performed.
E/M visits billed for complication care that did not involve a return to the operating room.
A reduced payment on a 10- or 90-day code appealed as an underpayment, when intraoperative-only payment is the rule.
How to prevent or fix
Confirm the setting and the link to the original surgery in the operative note.
Code the procedure actually performed, add 78 and the laterality modifier, and expect intraoperative-only payment for 10- and 90-day codes.
Check commercial policies. UnitedHealthcare’s Global Days Policy (2026R0005E, version dated September 20, 2026) pays 10- and 90-day codes billed with 78 at the CMS intraoperative percentage, which it says generally ranges from 60% to 84%, and does not start a new global period.
For related denial patterns, see our guide to common orthopedic claim denials.
Frequently asked questions
Does modifier 78 start a new global period?
No. Medicare contractor guidance states that a new postoperative period does not begin when modifier 78 is used, and UnitedHealthcare’s commercial policy says the same. The original procedure’s global period continues, so routine postoperative visits remain included in the original surgical payment until that period ends.
Can modifier 78 be used for complication care in a clinic treatment room?
Not for Medicare. Medicare defines an operating room as a place specifically equipped and staffed for procedures, and it excludes minor treatment rooms, recovery rooms and patient rooms, as well as intensive care units unless the patient’s condition is too critical to allow transport. Complication care in those settings is part of the global surgical package.
How does Medicare pay modifier 78 on a code with a 0-day global period?
In full. Codes with a 0-day global period have no separate pre-, intra- or postoperative values, so Medicare pays the full fee schedule amount when such a code is billed with modifier 78 for a return to the operating room to treat a complication. Codes with 10- or 90-day global periods are paid only their intraoperative portion.
Guides that cover this term
Related terms
Sources
Medicare Claims Processing Manual, Chapter 12: Physicians/Nonphysician Practitioners — CMS, Rev. 13753, issued May 7, 2026
Global Surgery (MLN907166) — CMS Medicare Learning Network, December 2025
Medicare NCCI Policy Manual, Chapter I: General Correct Coding Policies — CMS, revision date January 1, 2026
Modifier 78 Fact Sheet — WPS Government Health Administrators (Medicare Part B, J5 and J8), last updated October 28, 2023
Global Days Policy, Professional (Policy Number 2026R0005E) — UnitedHealthcare Commercial and Individual Exchange, version dated September 20, 2026
This entry is educational and is not legal, coding-compliance or billing advice. Payer rules change often, so confirm requirements with the payer before you bill. CPT® is a registered trademark of the American Medical Association; code descriptions here are Rette’s plain-language summaries.