Before the specialty surgical chapters, it helps to understand the structure that governs all of them. Surgical coding runs on one central concept, the global surgical package, and a small family of modifiers that carve exceptions out of it. Learn the structure once here, and the orthopaedic, fracture, and general-surgery chapters that follow become applications of a single idea rather than separate puzzles.
The Global Surgical Package
When you perform a procedure, its payment is not just for the minutes in the operating room. It bundles a defined set of related care into a single fee: the pre-operative evaluation on the day of surgery, the procedure itself, and the routine post-operative care for a set period afterward. That period is the global period, and it comes in three standard lengths: 0 days, 10 days for minor procedures, and 90 days for major ones. During the global period, routine related care is already paid for and is not separately billable.
This single fact explains most surgical coding confusion. The wound check, the suture removal, the uncomplicated follow-up after a 90-day-global operation: all bundled, all already paid. The skill of surgical coding is knowing what falls inside the package, which is not separately billable, and what falls outside it, which is.
The Modifiers That Carve Out Exceptions
A compact family of modifiers handles the legitimate exceptions to the package. Each says, in effect, this service is not the routine bundled care you would assume. The major ones, covered in depth in the chapters ahead:
- Modifier 57: the evaluation where the decision for major surgery was made, billable even though it falls in the immediate pre-operative window.
- Modifier 25: a significant, separate evaluation on the same day as a minor procedure.
- Modifier 24: an unrelated evaluation during the global period of a prior procedure.
- Modifier 58: a planned, staged, or more extensive related procedure during the global period.
- Modifier 78: an unplanned return to the operating room for a complication.
- Modifier 79: an unrelated procedure by the same surgeon during the global period.
Two more handle shared surgical work: Modifier 62 for co-surgeons who each perform a distinct part of one procedure, and Modifier 80 (or the AS modifier for an APP) for an assistant surgeon. Each splits the procedure's payment in a defined way.
Where the Money Leaks
Across every surgical specialty, the procedure itself is usually coded correctly, because operative coding is well-policed and the codes are specific. The revenue that goes uncaptured sits at the edges of the package: the decision-for-surgery visit that was bundled when it should have carried Modifier 57, the unrelated problem during the global period that was written off instead of coded with Modifier 24, the staged procedure undervalued by the wrong modifier. The chapters that follow are, in large part, about capturing that edge work accurately.
How the Surgical Chapters Are Organized
With this structure in hand, the surgical chapters proceed from the clinic inward. The orthopaedic chapter covers the evaluation-and-global side of a surgical practice. The fracture chapter handles a package that behaves unusually. The general-surgery chapter works through the modifier family in operative detail. Each leans on the global-package concept established here, so this overview is worth returning to if a later modifier rule seems to come from nowhere.
Sources and Further Reading for This Chapter
- CMS, Global Surgery Booklet (MLN). https://www.cms.gov/files/document/mln907166-global-surgery-booklet.pdf