Summary & Overview
CPT 27446: Partial Knee Arthroplasty, Medial or Lateral Compartment
CPT code 27446 is a nationally recognized billing code for partial knee arthroplasty, targeting either the medial or lateral compartment of the knee. This procedure is a critical option for patients with localized joint damage, offering an alternative to total knee replacement. The code is widely used in orthopedic surgery and is most commonly performed in hospital inpatient settings, reflecting the complexity and recovery needs associated with knee joint reconstruction.
Major payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, Medicare, and UnitedHealthcare. Understanding how these payers approach reimbursement and policy for CPT code 27446 is essential for providers, administrators, and policy analysts seeking to benchmark utilization, review clinical indications, and stay informed about evolving coverage criteria.
Readers will gain insights into the clinical context of partial knee arthroplasty, current billing practices, and relevant policy updates. The publication also highlights associated diagnoses, common modifiers, and related codes, providing a comprehensive overview for stakeholders in orthopedic surgery and medical billing. This summary serves as a resource for understanding national trends and payer perspectives on partial knee replacement procedures.
CPT Code Overview
CPT code 27446 describes an arthroplasty of the knee, specifically involving the condyle and plateau of either the medial or lateral compartment. This procedure is a form of orthopedic surgery typically performed to address joint damage or disease affecting one compartment of the knee. The most common site of service for this procedure is the hospital inpatient setting (Place of Service 21), where patients receive comprehensive care during their surgical stay. This code is used to identify and bill for partial knee replacement surgeries that focus on a single compartment, distinguishing it from total knee arthroplasty procedures.
Clinical & Coding Specifications
Clinical Context
A typical patient scenario involves an adult patient admitted to the hospital with a malignant neoplasm affecting the long bones, peripheral nerves, or connective and soft tissue of the lower limb, including the hip. The patient presents with pain, functional impairment, or structural compromise of the knee joint due to the tumor. The orthopedic surgeon evaluates the extent of disease and determines that a partial knee arthroplasty is indicated to restore joint function and alleviate symptoms. The procedure described by CPT code 27446 is performed, replacing the condyle and plateau of either the medial or lateral compartment of the knee. The clinical workflow includes preoperative imaging, surgical planning, intraoperative tumor resection as needed, and compartmental knee arthroplasty, followed by postoperative care and rehabilitation.
Coding Specifications
| Modifier Code | Description | Usage |
|---|---|---|
RT | Right side | Used when the procedure is performed on the right knee. |
LT | Left side | Used when the procedure is performed on the left knee. |
59 | Distinct Procedural Service | Used when the procedure is distinct from other services performed on the same day. |
51 | Multiple Procedures | Used when multiple procedures are performed during the same operative session. |
Associated Provider Taxonomies:
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207X00000X– Orthopaedic Surgery: Specialists in surgical treatment of musculoskeletal conditions. -
207XX0004X– Orthopaedic Surgery of the Spine: Specialists focusing on surgical interventions of the spine. -
207XS0114X– Orthopaedic Trauma: Specialists in surgical management of traumatic musculoskeletal injuries.
Related Diagnoses
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C40.21– Malignant neoplasm of long bones of right lower limb- Relevant when the tumor affects the right femur or tibia, potentially necessitating knee arthroplasty.
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C40.22– Malignant neoplasm of long bones of left lower limb- Indicates malignancy in the left femur or tibia, which may compromise knee integrity.
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C47.21– Malignant neoplasm of peripheral nerves of right lower limb, including hip- Used when cancer involves peripheral nerves near the right knee or hip, possibly impacting joint function.
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C47.22– Malignant neoplasm of peripheral nerves of left lower limb, including hip- Applies to malignancy of peripheral nerves in the left lower limb, affecting knee stability or function.
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C49.20– Malignant neoplasm of connective and soft tissue of unspecified lower limb, including hip- Used for soft tissue tumors in the lower limb, which may require surgical intervention at the knee.
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C49.21– Malignant neoplasm of connective and soft tissue of right lower limb, including hip- Indicates soft tissue malignancy in the right lower limb, potentially necessitating knee arthroplasty.
Related CPT Codes
27447– Arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing (total knee arthroplasty)
Clinical Relationship:
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CPT code
27447represents a total knee arthroplasty, involving both medial and lateral compartments, and may include patella resurfacing. It is related to CPT code27446, which is for partial knee arthroplasty (medial OR lateral compartment). -
In clinical workflow,
27447is used when both compartments require replacement, whereas27446is used for single compartment involvement. These codes are alternatives depending on the extent of disease or damage. They are not typically used together in the same operative session.
National Reimbursement Benchmarks
Nationally, the mean rate for CPT code 27446 under Medicare is $1,063.35, while the BUCA (average commercial) mean rate is $1,508.84. Commercial payers such as UnitedHealth Group and Cigna have notably higher mean rates, with UnitedHealth Group at $2,074.97 and Cigna at $1,881.75. Blue Cross Blue Shield and Aetna fall between these extremes, with mean rates of $1,525.42 and $1,026.32, respectively.
Rate dispersion, measured by the difference between the 75th and 25th percentiles, varies significantly across payers. Aetna shows the tightest range at $575.25, indicating less variability in rates, while UnitedHealth Group exhibits the widest range at $1,207.50, reflecting greater variability. Cigna and Blue Cross Blue Shield also display substantial dispersion, with ranges of $1,102.50 and $842.39, respectively. Medicare's range is the narrowest among all, at $81.00.
The table and chart below present the full breakdown of national benchmarks for CPT code 27446 across major payers.
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