CPT code 27524 – Open treatment of patellar fracture

Key takeaways

CPT Code 27524 covers open (surgical) treatment of patellar fracture, which separates it from 27520, the only closed-treatment patellar fracture code.

The 90-day global period bundles all routine post-op visits, so billing standard follow-up separately within that window triggers denials.

A missing laterality modifier (LT/RT) and an operative report that omits which descriptor components were performed are frequent denial triggers.

Pabau’s claims management software works with the Claim.MD clearinghouse to help catch missing modifiers and code mismatches before submission.

CPT Code 27524: Official descriptor and clinical definition

CPT Code 27524 has an official descriptor set by the American Medical Association.

It reads: “Open treatment of patellar fracture, with internal fixation and/or partial or total patellectomy and/or repair of retinaculum.” The “and/or” construction means the code covers any combination of those three components. Fixation alone, patellectomy alone, or either one with retinacular repair is still reported once as 27524. What separates it from the closed treatment code 27520 is that the surgeon opens the fracture site.

Clinical procedure: What happens during open patellar fracture surgery

Open treatment of patellar fracture begins with the patient supine under general or spinal anesthesia. The surgeon makes a midline or parapatellar incision over the kneecap and directly inspects the fracture pattern before choosing a fixation strategy. That choice drives what the operative report must document for 27524.

• Tension band wiring (TBW): Used for transverse fractures. Kirschner wires are placed longitudinally through the patella and a figure-of-eight wire loop is applied anteriorly, converting tensile forces to compressive forces across the fracture.
• Cannulated screw fixation: Used for longitudinal or less comminuted patterns. Partially threaded cancellous screws provide lag-screw compression. Often combined with an anterior tension band for stability.
• Plate fixation: Reserved for highly comminuted fractures where fragment count makes TBW unreliable. Low-profile locking plates may be used along the superior or anterior pole.
• Partial patellectomy: When a pole fragment is too small to hold hardware, the surgeon excises it. The extensor mechanism is then repaired back to the remaining patella.
• Total patellectomy: Reserved for severely comminuted, unreconstructable fractures. The entire patella is removed and the quadriceps and patellar tendons are repaired.
• Retinacular repair: Often performed, because the medial or lateral retinaculum commonly tears with a displaced fracture. Coders cannot assume it was done, so the operative report has to state it.

Fluoroscopy confirms reduction and hardware position intraoperatively. Intraoperative fluoroscopy (CPT 76000) is generally bundled into 27524 under NCCI edits. Verify the current edit table before billing it separately.

What CPT 27524 includes and excludes (bundling rules)

The 90-day global surgical package for 27524 bundles most routine post-operative care. The table shows which services are included and which can be billed separately with the right modifier.

CPT 27524 vs. similar patellar fracture codes

Choosing the right code from the patellar fracture family depends on whether the fracture site was surgically exposed. CPT 27520 is the only closed-treatment code for a patellar fracture, and the next code in the family is 27524. The table below shows the distinctions coders check in the operative report before assigning a code.

ICD-10 diagnosis codes to pair with CPT 27524

Patellar fracture diagnosis codes fall under ICD-10-CM subcategory S82.0. Every code requires a laterality character and a 7th-character extension reflecting the encounter type. Getting the 7th character wrong is a frequent denial trigger. Use the CDC ICD-10-CM tabular list to verify the full code set for each operative scenario.

7th character rules: Use “A” for the initial encounter when the fracture is closed and the surgeon performs definitive open treatment. Use “B” for an open type I or II fracture, and “C” for an open type IIIA, IIIB or IIIC fracture. A closed displaced transverse fracture of the right patella, a pattern that often goes to ORIF, is reported as S82.031A.

Follow-up visits, hardware checks and physical therapy use the subsequent-encounter characters (D through S). A surgery claim that carries a “D” character signals that treatment is already in progress, so payers reject it.

90-day global period for CPT 27524: What is and isn’t billable

The 90-day global period for CPT Code 27524 means that all routine post-operative care through day 90 is bundled into the surgical fee. The timeline below shows the three billing windows around the surgery, and the modifier that unlocks each separate charge.

• Day 0 (day of surgery): Pre-operative evaluation on the day of surgery is bundled unless a separate, unrelated problem is addressed and documented.
• Days 1–90 (routine follow-up): Standard wound checks, suture removal, cast changes, and functional progress evaluations are all bundled. An E/M billed for these visits without a modifier is denied as part of the global package.
• Modifier 24 (unrelated E/M during global): Applies when a post-op visit addresses a problem entirely unrelated to the patellar fracture. The documentation must clearly demonstrate the unrelated nature of the visit.
• Modifier 78 (return to OR for complication): Applies when a complication requires a second surgical procedure during the global period. Hardware failure and wound dehiscence needing irrigation and debridement are typical examples.
• Modifier 79 (unrelated procedure during global): Applies when a staged or unrelated surgical procedure is performed within the 90 days. The diagnosis must differ from the patellar fracture.

Medicare reimbursement rate for CPT Code 27524

Medicare pays CPT Code 27524 under a 090 global period, so one fee covers the surgery and 90 days of routine post-operative care. PayerPrice lists the 2026 national Medicare non-facility rate at $705.09, before geographic adjustment.

Each MAC region adjusts that figure with its geographic practice cost index (GPCI). Use the CMS Physician Fee Schedule Look-Up Tool to pull the current RVUs and the facility and non-facility rates for your locality.

Rates change each January when CMS publishes the final physician fee schedule rule. Never quote a Medicare rate to a patient or payer without pulling the current locality-adjusted amount from the CMS look-up tool.

Documentation requirements for CPT 27524

Payers audit 27524 claims against the operative report. A note that simply states “ORIF patella” gives a reviewer grounds to downcode or deny. It needs the fracture pattern, approach, fixation method, and any additional procedures. The operative report is the most important document in a clean claim package for 27524.

• Fracture pattern: Document the fracture type (transverse, comminuted, osteochondral, longitudinal) and displacement status. This maps to the specific ICD-10 subcategory code and validates medical necessity for surgical intervention.
• Surgical approach: Name the incision type (anterior midline, parapatellar, lateral). This confirms “open treatment” and distinguishes 27524 from closed treatment codes.
• Fixation method and hardware: State the specific technique (tension band wiring with K-wires, cannulated screws, locking plate) and the hardware used (manufacturer, size where relevant). This supports the internal fixation component of the descriptor.
• Retinacular repair: If the medial or lateral retinaculum was repaired, document it explicitly. The descriptor includes “repair of retinaculum” as one of its components. Work the note does not record cannot be coded, even if it was performed.
• Patellectomy (if performed): Document whether a partial or total patellectomy was performed and the reason (non-viable fragment, severe comminution). This maps to the patellectomy component and can affect medical necessity review.
• Fluoroscopy: Note that intraoperative fluoroscopy was used for reduction and hardware confirmation. Intraoperative fluoroscopy (CPT 76000) is generally bundled under NCCI edits, so check the current edit table before billing it separately.
• Post-operative stability: Record the range of motion check and extensor mechanism integrity assessment performed at closure. This is not separately billable but supports appropriateness review.

Modifiers commonly used with CPT 27524

Modifier selection for 27524 claims determines whether a claim pays, pays reduced, or denies outright. The following modifiers appear most frequently on patellar ORIF claims.

Prior authorization requirements for CPT 27524

Prior authorization requirements for CPT Code 27524 vary by payer and cannot be generalized. Medicare generally does not require prior authorization for medically necessary fracture ORIF, but commercial insurers frequently do. Verify requirements with each specific plan before scheduling. Strong revenue cycle management processes include checking prior auth at patient registration, not at the time of billing.

• Medicare: Fracture ORIF is typically not on CMS’s prior authorization required procedure list for traditional Medicare. Medicare Advantage plans may have their own requirements; verify separately.
• Commercial payers: Commercial plans such as Aetna, UnitedHealthcare, Cigna and Anthem often require prior authorization for elective orthopedic surgery. Trauma presentations with same-day surgery may bypass auth requirements, but document the emergency nature clearly.
• Documentation typically required: X-ray or CT imaging reports confirming fracture displacement, surgeon attestation of medical necessity, and the operative plan. Elective cases also need documentation that conservative management was considered or attempted.

Common claim denial reasons for CPT 27524 and how to prevent them

Denied 27524 claims usually trace back to a short list of fixable problems. Effective denial management workflows should track these triggers by payer so patterns can be addressed at the source. For a complete reference on denial codes in medical billing, cross-reference your CARC codes against the specific 27524 scenarios below.

How Pabau catches CPT 27524 claim errors before submission

Without a pre-submission check, a missing LT/RT modifier or a wrong 7th character usually surfaces only when the denial comes back. Each one costs a corrected claim, a resubmission and another wait for payment.

Pabau’s claims management software lets practice teams build pre-submission scrubbing rules and flag claims with missing modifiers before they reach the payer. The same tools track denial trends across CPT codes, including 27524.

Claims then go out through the Claim.MD clearinghouse integration, and claim status comes back into the same system. The billing team sees which 27524 claims are pending, paid or denied without logging into a separate portal.

Manage orthopedic claims without the manual follow-up

Pabau integrates with Claim.MD to validate CPT and ICD-10 codes before submission, flag missing modifiers, and track claim status across your orthopedic cases.

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Conclusion

CPT Code 27524 is straightforward to assign once the operative report confirms an open approach. Denials come from the paperwork around it. The usual culprits are a missing LT/RT modifier, a wrong 7th character, or a note that never names the components performed.

Check those three items on every 27524 claim before submission, not after the first denial. Fixing the operative note template once costs less than reworking each rejected claim. Book a demo to see how Pabau checks orthopedic claims from the encounter through to payment.

Continue your research

Need a clearinghouse for orthopedic claim submissions? Pabau’s Claim.MD clearinghouse integration explains how electronic claim validation works for US practices billing CPT codes.

Want to understand the full 837 claim submission process? Electronic 837 claim files covers the EDI transaction set used to submit CPT 27524 and other surgical claims to payers.

Getting ERA data back after claim adjudication? Electronic remittance advice (ERA) explains how to read 835 remittance files and match payments to your 27524 submissions.

Frequently asked questions