Why it matters in orthopedics
Orthopedic patients often need care for more than one joint or injury. A patient still in the global period after a knee replacement may need a carpal tunnel release, a trigger finger release or a shoulder injection, or may fall and fracture a wrist. Medicare denies a procedure with its own global period performed during another procedure’s postoperative period unless it carries modifier 58, modifier 78 or modifier 79 (Medicare Claims Processing Manual, Chapter 12, §40.4.A).
How it works
A new postoperative period begins when the unrelated procedure is billed.
Clearly distinct procedures that are not re-operations or complication treatment fall outside the original global surgical package (§40.1.B).
For an unrelated visit rather than a procedure, use modifier 24 on the E/M.
Planned or staged procedure, more extensive procedure, or therapy after a diagnostic procedure | |
Unplanned return to the operating room for a related problem | |
Orthopedic example
A left shoulder injection during the knee’s global period would also take modifier 79. If a separately identifiable E/M happens that day, it carries modifiers 24 and 25; our injection-day guide explains that combination.
Common denial triggers
A related procedure on the same joint is billed with 79 instead of 58 or 78.
Laterality modifiers are missing, so the payer cannot tell the procedures apart.
How to prevent or fix
Frequently asked questions
Does modifier 79 start a new global period?
Yes. Medicare’s Claims Processing Manual and CMS’s global surgery booklet both state that a new postoperative period begins when the unrelated procedure is billed with modifier 79. Track it in your practice management system so routine follow-up for the new procedure is not billed as separate visits, while visits for other unrelated problems still get modifier 24.
Is modifier 79 needed for an X-ray during the global period?
No. Medicare pays codes with an XXX global surgery indicator during a global period without a modifier, and diagnostic tests and procedures, including diagnostic radiology, are not part of the global surgical package. Modifier 79 is for procedures that carry their own global period, such as joint injections or carpal tunnel release.
Can modifier 79 be used on an evaluation and management visit?
No. Modifier 79 is for procedures. An unrelated E/M visit during a postoperative period is reported with modifier 24, and if a separately identifiable E/M occurs on the same day as another procedure during that period, CMS’s global surgery booklet calls for modifiers 24 and 25 together on the E/M.
Guides that cover this term
The Most Common Orthopedic Claim Denials in 2026, and How to Prevent Them
Ten orthopedic denial types, the CARCs behind them, their root causes and how to prevent them, plus when to appeal or correct and resubmit.
→
Can You Bill an E/M With Modifier 25 on an Orthopedic Injection Day?
Medicare rules, payer policies and a scenario table for billing a same-day E/M with modifier 25 alongside knee, shoulder and hip injections.
→
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
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.