Orthopedic surgery generates some of the highest per-claim values in outpatient medicine — and some of the most specific billing rules. A surgical claim that misses an implant charge, applies the wrong global period modifier, or bills a commercial payer under workers’ comp rules loses thousands of dollars that would have been collectible with the right billing workflow.
Problem 1: 90-Day Global Surgical Packages
Major orthopedic procedures carry a 90-day global period during which all related E/M services, routine follow-up, and post-op care are bundled into the surgical fee. Billing a follow-up visit during the global period — without the correct modifier — generates a CO-97 bundling denial.
The modifiers that allow separate billing during the global period:
| Modifier | Use | Documentation Required |
|---|---|---|
| -24 | Unrelated E/M service during global period | Documentation must clearly show the visit was for a condition unrelated to the surgical procedure |
| -25 | Significant separate E/M on day of procedure | Significant, separately identifiable medical service beyond the pre-op evaluation |
| -58 | Staged or related procedure during global period | Planned staged procedure or more extensive procedure than originally planned |
| -78 | Unplanned return to OR for related procedure | Complication requiring unplanned return to operating room |
| -79 | Unrelated procedure during global period | Separate procedure for a condition unrelated to the original surgery |
The systematic error: billing post-op follow-up visits without tracking which visits fall inside the global period versus outside it. A patient who had a knee replacement and presents 45 days later for a shoulder issue should have the shoulder visit billed with -24 (unrelated). A billing team that isn’t tracking global periods either misses that modifier or incorrectly bundles the visit.
Problem 2: Implant and Surgical Supply Charge Capture
Orthopedic surgery frequently involves implants — plates, screws, joint replacement components, bone grafts. These implants are separately billable supply items with significant per-unit costs. A total knee replacement may involve $8,000–$15,000 in implant components that are billed as supply charges alongside the surgical procedure.
The billing error: implant charges not captured at all. The surgeon places the implant, the operative note documents it, but the charge doesn’t make it into the billing system because the charge capture workflow doesn’t systematically pull implant data from the OR supply record.
At $5,000–$15,000 per missed implant charge, even a few missed cases per month represents $10,000–$45,000/month in unrecovered revenue — never a denial, just a charge that never entered the system.
Problem 3: Workers’ Compensation Volume in Orthopedics
Orthopedic practices have a disproportionate share of workers’ compensation patients — workplace injuries, repetitive stress injuries, and occupational conditions are primary drivers of orthopedic referrals. Workers’ comp billing follows completely different rules than health insurance (see our workers’ comp billing guide), and mixing the two billing workflows creates systematic errors in both directions.
The most common error: billing workers’ comp claims to the patient’s health insurance instead of the employer’s workers’ comp carrier. The health insurer processes the claim (or denies it as work-related injury not covered), and the workers’ comp carrier doesn’t receive a bill. Months later, the practice discovers the billing error when the health insurer demands repayment or the statute of limitations on the workers’ comp claim has shortened.
Frequently Asked Questions
What is the global period in orthopedic surgery billing?
The global period is a defined post-operative period during which all routine follow-up care and related E/M services are bundled into the surgical fee and cannot be billed separately. Major orthopedic procedures carry a 90-day global period. Billing separate follow-up visits during this period requires a modifier (-24, -58, -78, -79) and documentation establishing the visit is either unrelated to the original surgery or qualifies as a separately reportable service.
How are implants billed in orthopedic surgery?
Orthopedic implants (L-codes for DME/prosthetics, or supply/device codes) are billed separately from the surgical procedure code. The billing requires the implant manufacturer, catalog number, and cost from the OR supply record. Capture depends on a workflow that pulls implant data from the operative supply documentation into the billing system for every surgical case. Missing this step results in implant costs absorbed by the practice rather than billed to the payer.
Does orthopedics have higher prior authorization requirements?
Yes — particularly for elective surgical procedures. Most commercial payers require prior authorization for joint replacement surgery, arthroscopic procedures, and spinal surgery. Authorization must cover not just the procedure but the facility and anesthesia provider. Some payers also require pre-authorization for high-cost implants separately from the surgical authorization. Tracking all components of orthopedic surgical authorization requires a dedicated workflow.
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Related Resources
Orthopedic billing specialists | Workers comp billing guide | Prior authorization guide