Summary & Overview
CPT 27599: Unlisted Procedure for Femur or Knee in Orthopedic Surgery
CPT code 27599 is an unlisted procedure code for the femur or knee, used in orthopedic surgery when no specific CPT code accurately describes the surgical service performed. This code is nationally relevant as it provides a mechanism for reporting unique or uncommon procedures that do not fit established coding categories, ensuring appropriate documentation and billing for complex orthopedic cases.
Major payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, and UnitedHealthcare. The publication offers insights into payer coverage policies, typical sites of service, and the clinical context in which CPT 27599 is utilized. Readers will learn about the benchmarks for reporting unlisted orthopedic procedures, relevant modifiers, and associated taxonomies. The summary also highlights common clinical scenarios, such as knee pain, femur fractures, and osteoarthritis, where this code may be applicable. Additionally, related CPT codes are discussed to provide context for how CPT 27599 fits within the broader landscape of orthopedic billing and coding.
This article is designed to inform healthcare professionals, billing specialists, and policy analysts about the national significance of CPT 27599, its clinical applications, and payer considerations for orthopedic surgical procedures that require unlisted coding.
CPT Code Overview
CPT 27599 is designated as an unlisted procedure for the femur or knee within the field of orthopedic surgery. This code is used when a surgical intervention involving the femur or knee does not have a specific CPT code assigned. Procedures billed under CPT 27599 are typically performed in an outpatient hospital setting (Place of Service 22). The unlisted status of this code allows for flexibility in reporting unique or uncommon orthopedic surgical procedures that fall outside the scope of established codes.
Clinical & Coding Specifications
Clinical Context
A patient presents to the outpatient hospital with persistent pain in the knee or following a traumatic injury to the femur. The orthopedic surgeon evaluates the patient and determines that a specialized procedure is required, which does not fit any standard CPT code for femur or knee interventions. This may involve a unique surgical approach, device placement, or repair technique for complex fractures or advanced osteoarthritis. The procedure is performed by an orthopedic surgery specialist, and documentation is prepared for submission using CPT code 27599 to represent the unlisted procedure. The workflow includes preoperative assessment, surgical intervention, and postoperative care, with coding and billing staff ensuring proper use of modifiers and supporting documentation for payor review.
Coding Specifications
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Modifier
51(Multiple Procedures):- Used when more than one procedure is performed during the same operative session. Indicates that multiple procedures are being reported.
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Modifier
59(Distinct Procedural Service):- Used to identify procedures/services that are not normally reported together, but are appropriate under the circumstances. Indicates a distinct procedural service from others performed on the same day.
| Taxonomy Code | Specialty Name |
|---|---|
207X00000X | Orthopaedic Surgery Physician |
207XX0004X | Orthopaedic Trauma Physician |
207XS0117X | Orthopaedic Surgery of the Spine Physician |
Related Diagnoses
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M25.561- Pain in right knee- Indicates the patient is experiencing pain localized to the right knee, which may necessitate an unlisted procedure if standard treatments are not applicable.
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M25.562- Pain in left knee- Represents pain in the left knee, relevant for procedures addressing non-specific or complex knee pain.
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S72.001A- Fracture of unspecified part of neck of right femur, initial encounter for closed fracture- Used for initial treatment of a closed fracture in the neck of the right femur, potentially requiring a unique surgical approach coded as
27599.
- Used for initial treatment of a closed fracture in the neck of the right femur, potentially requiring a unique surgical approach coded as
-
S72.002A- Fracture of unspecified part of neck of left femur, initial encounter for closed fracture- Indicates a closed fracture in the neck of the left femur, relevant for unlisted procedures when standard fracture repair codes do not apply.
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M17.11- Unilateral primary osteoarthritis, right knee- Represents primary osteoarthritis in the right knee, which may require specialized or unlisted surgical intervention if conventional procedures are not suitable.
Related CPT Codes
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27447- Total knee arthroplasty- Used for complete replacement of the knee joint. May be considered as an alternative to
27599if the procedure performed is a standard knee replacement.
- Used for complete replacement of the knee joint. May be considered as an alternative to
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27506- Open treatment of femoral fracture, proximal end, neck, internal fixation or prosthetic replacement- Used for open surgical treatment of femoral neck fractures. If the procedure is not standard or involves unique techniques,
27599may be used instead.
- Used for open surgical treatment of femoral neck fractures. If the procedure is not standard or involves unique techniques,
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29881- Arthroscopy, knee, surgical; with meniscectomy (medial OR lateral, including any meniscal shaving)- Used for arthroscopic removal or shaving of the meniscus. If the procedure is not covered by this code,
27599may be appropriate.
- Used for arthroscopic removal or shaving of the meniscus. If the procedure is not covered by this code,
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20610- Arthrocentesis, aspiration and/or injection into a major joint or bursa- Used for aspiration or injection procedures in major joints. If a more complex or unlisted procedure is performed,
27599is used.
- Used for aspiration or injection procedures in major joints. If a more complex or unlisted procedure is performed,
These codes may be used together in cases where multiple procedures are performed, or as alternatives when the procedure does not fit a standard CPT code.
National Reimbursement Benchmarks
Nationally, the mean rate for CPT code 27599 is highest with Blue Cross Blue Shield at $5,325.56, while Cigna is lowest among major commercial payers at $446.99. The BUCA (average commercial) mean rate stands at $3,142.84, which is substantially higher than typical Medicare rates for similar codes, though Medicare data is not available in the input for this code.
Rate dispersion varies significantly across payers. Blue Cross Blue Shield shows the widest spread, with a difference of $58.00 between the 75th and 25th percentiles, while Cigna and BUCA have much tighter ranges ($20.00 and $135.14, respectively). Aetna and UnitedHealth Group display moderate dispersion, with ranges of $1,662.33 and $1,229.00, respectively. This indicates that some payers have more consistent reimbursement rates, while others vary widely.
The table and chart below present the full breakdown of national benchmarks for CPT code 27599 across major payers.
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