Home Specialities General Surgery
High-acuity surgery
open & laparoscopic
Surgery-certified coders
operative-note review
All major payers
commercial, Medicare & MA
Underpayment recovery
on claims marked paid
The 90-day window is where your surgical revenue quietly disappears.
Ask a surgical practice about revenue-cycle pain and you'll hear prior auth, infection documentation, and A/R days. Some problems are real and obvious. They are the loud ones. Not the most expensive. The most expensive one clears cleanly and posts as paid: an assistant's line zeroed, an unrelated post-op visit denied, an hour of extra dissection reimbursed at the routine rate.
Across the 29 general surgery revenue cycles we've analyzed, an average of 4.3–7.2% of gross revenue is withheld this way. On a $12M practice, that can mean $516K to $864K a year, and it compounds across every payer contract cycle.
See what got swept inWhat 4.3–7.2% looks like on a $12M practice
The 4.3–7.2% range reflects OneMed's analysis of 29 general surgery revenue cycles; the dollar figures apply that range to a $12M example practice. Your actual exposure depends on payer mix, case mix, and documentation.
The global period bundles routine care — not everything.
Plenty of work around a surgery is legitimately separate and separately payable when the right modifier is attached and supported by documentation. Drop it, and the payer keeps it inside the package at $0. Here's what should break out.
| Around the surgery | Payer's default | Breaks out with | If the modifier's dropped |
|---|---|---|---|
| Office visit where surgery is decided | "Pre-op, included" | Modifier 57 | E/M paid $0 |
| Assistant surgeon's work | "Not authorized" | Mod 80 / 82 / AS | Assistant paid $0 |
| Extra dissection / open conversion | "Included in procedure" | Modifier 22 | Extra work unpaid |
| Unrelated visit, day 21 post-op | "Post-op care" | Modifier 24 | Visit denied |
| Return to OR for a complication | "Post-op care" | Modifier 78 | Return paid $0 |
These examples show common ways global-period rules are misapplied. Modifier use depends on the specific encounter, documentation, and payer policy.
Five ways surgical work gets kept inside the package.
General surgery billing is a maze of global periods, assistant rules, and documentation links. These are the underpayment patterns we find most often, on claims that already say "paid."
Global-period modifier erasure (24/58/78/79)
General surgery carries 0-, 10-, and 90-day global periods. A return within the global period may be unrelated to the original surgery, staged or related, caused by a complication requiring a return to the OR, or an unrelated procedure. Modifiers 24, 58, 78, and 79 identify those situations and can support separate payment. Payers see a code inside the global window and pay $0 with "included in global surgical package."
Assistant surgeon zeroed (80/82/AS)
Complex cases need an assistant; the assistant's work bills with Modifier 80, 82, or AS and pays a set percentage of the surgeon's fee. Payers may zero out the assistant surgeon line as “assistant not authorized” or “not medically necessary,” even when the assistant was documented and appropriate.
Decision-for-surgery downgrade (Modifier 57)
When the decision for major surgery is made at an office visit, Modifier 57 makes that E/M separately payable even though it falls in the global period. Payers bundle it as "pre-operative work" when the note doesn't explicitly document the decision.
Increased work & open conversion (Modifier 22)
Dense adhesions, an extra hour of dissection, or a laparoscopic case converted to open may represent increased procedural work. That work can be reported with Modifier 22 or the appropriate codes when documentation supports it. Payers deny Mod 22 outright or grant a token increase, and pay open conversions at the laparoscopic rate.
Complex-patient E/M downgrade
Surgical patients carry heavy comorbidities and extensive workup that justify high-level E/M (99214/99215, 99204/99205). Payers apply blanket downgrades to 99213/99203, ignoring the real complexity.
The assistant's share is a real number. Watch it pay zero.
When an assistant surgeon is medically necessary and documented, Medicare reimburses the assistant at roughly 16% of the surgeon's fee schedule, billed with Modifier 80, 82, or AS. That's a defined, separately-payable amount.
Payers may zero out the assistant line as “assistant not authorized,” even when the assistant was appropriate and documented. The rule is public; you can check the assistant lines on your own remits.
See it on your own claimsThe assistant's 16%, paid at 0%
Medicare reimburses an assistant at surgery at roughly 16 percent of the surgeon’s fee schedule. The $2,000 figure is illustrative, and commercial rates vary. Confirm against your contracts. Assistant eligibility depends on the procedure.
Bandwidth, not effort
Your billing team is not failing. They are buried in surgical scheduling and prior authorization work while back-end payments often go unaudited.
The "paid means paid" blind spot
Your team chases $0 rejections. When a claim is marked paid, the file usually closes, even if the assistant line or an unrelated post-op visit was zeroed inside it.
No global-period tracking
When a patient returns weeks after surgery, few workflows flag whether the visit was related or unrelated. As a result, Modifier 24, 58, 78, or 79 opportunities may never be captured, and the visit pays $0.
No assistant-surgeon verification
Most practices submit the assistant claim, see the case marked paid, and never check whether the assistant’s portion was silently reduced to zero.
We pull your separate work back out of the package.
Seamless workflow integration plus general-surgery-certified coders. We work inside your existing practice management system, with no EHR change and no disruption, and counter rigid payer rules with reviewers who read the operative note.
ClearView operational visibility
Our ClearView dashboard flags when a cholecystectomy with extensive adhesiolysis paid like a routine case, an assistant line was zeroed, or a post-op E/M was erased, without changing how your staff logs in.
Expert clinical chart audit
Flagged claims route to our general-surgery-certified coders, who work inside your system to read the operative report, verify the procedures and assistant documentation, and check whether a global-period encounter qualifies for Modifier 24/58/78/79.
Targeted clinical appeal
We draft documentation-backed appeals that prove the unrelated visit, the complication return, the assistant’s role, or the increased procedural work.
Payer pattern mapping
We track which payers erase your Modifier 24 or deny your Modifier 22, then pursue systematic corrections and contract fixes instead of treating each claim as a one-off issue.
The 2026 OneMed General Surgery Revenue Leak Index.
We don't rely on hypothetical math or isolated stories. We reviewed anonymized data from every general surgery revenue cycle we audited over the last 18 months. The pattern was clear.
29
surgery revenue cycles audited
142,000+
claims audited
$3.09M
recovered for clients
89.1%
recovery rate on appeals
Of that $3.09M, this is where the money had been hiding. The work that should break out of the global package is exactly where the money is kept in.
| Underpayment pattern | Share of recovered value |
|---|---|
| E/M downgrades on complex surgical patients | 26% |
| Global-period modifier erasure | 23% |
| Assistant surgeon modifier traps | 21% |
| Increased-work & open-conversion bundling | 18% |
| Decision-for-surgery downgrades | 12% |
These results were aggregated across OneMed general surgery underpayment audits over the trailing 18 months, with $3.47M identified and $3.09M recovered. Individual results vary by payer, documentation, and contract terms.