Orthopedic Coding Alert

Modifier -51 (multiple procedures) has been used widely in orthopedic settings, where surgeries of the hand, knee, foot or shoulder can often result in numerous procedures being done at the same time. Although there is still some confusion concerning the use of modifier -51, increasingly, orthopedic coders report that carriers including Medicare no longer require it.

When to Use Modifier -51

Modifier -51 typically has been used when the same physician performs multiple procedures in the same session. CPT 2000 describes use of -51 as follows:

When multiple procedures, other than E/M services, are performed at the same session by the same provider, the primary procedure or service may be reported as listed. The additional procedure(s) may be identified by appending the modifier -51 to the additional procedure or service code(s) or by use of the separate five-digit modifier 09951.

The July 1999 CPT Assistant further clarifies the proper use of modifier -51:

It does not apply to evaluation and management (E/M) codes, designated add-on codes, or codes designated as modifier -51 exempt. The use of the -51 modifier is not restricted to operative procedures, although it is commonly used in this context.

Section 4826 Claims for Multiple Surgeries in the Medicare Carriers Manual Part 3 provides further rules for billing with modifier -51:

B. Billing Instructions. Instruct billers to use the following guidelines when billing for multiple surgeries by the same physician on the same day.

Report the more major surgical procedure without the multiple procedures modifier - 51.
Report additional surgical procedures performed by the surgeon on the same day with modifier -51.

Medicares reimbursement rate for multiple procedures has become the industry standard for claims payment, with most commercial carriers adopting a similar payment policy. It allows for base payment for each ranked procedure on the lower of the billed amount or 100 percent of the scheduled fee amount for the highest valued procedure and 50 percent of the scheduled fee amount for the second through fifth highest valued procedures.

Where to Use Modifier -51

Kerstin Conner, billing specialist at Orthopedic Foot and Ankle Center, a two-surgeon practice in Columbus, Ohio, expresses some confusion over the proper use of modifier -51. We are told to use it different ways, says Conner, such as only when there is more than one surgery code billed or only when there are multiple surgeries done in the same area or the same incision.

She says that they typically append modifier -51 when billing for 27640 (partial excision [craterization, saucerization, or diaphysectomy] bone [e.g., osteomyelitis or exostosis]; tibia) when done in conjunction with 29898 (arthroscopy, ankle [tibiotalar and fibulotalar joints], surgical; debridement, extensive) and 28120 (partial [...]