Summary & Overview
CPT 97018: Paraffin Bath Application in Physical Medicine and Rehabilitation
CPT code 97018 is a nationally recognized billing code for the application of a paraffin bath modality in physical medicine and rehabilitation. This procedure is widely used in outpatient clinics and therapy departments to deliver therapeutic heat to one or more areas, aiding in the management of pain and mobility issues. The code is relevant for a range of clinical scenarios, including joint pain, fibromyalgia, and low back pain, making it a staple in rehabilitation therapy.
Major payers covering this service include Aetna, Blue Cross Blue Shield, Cigna Health, Medicare, and UnitedHealthcare. Understanding coverage policies and billing requirements for these payers is essential for providers and billing professionals to ensure accurate reimbursement and compliance.
This publication provides a comprehensive overview of CPT code 97018, including clinical context, payer coverage, and related billing considerations. Readers will gain insights into typical sites of service, common modifiers such as 59 and 76, associated provider taxonomies, and relevant ICD-10 diagnoses. The report also highlights related CPT codes, offering a broader perspective on modality-based therapies in rehabilitation. Policy updates and benchmarks are included to inform stakeholders of current trends and requirements in medical billing for paraffin bath applications.
CPT Code Overview
CPT code 97018 describes the application of a modality to one or more areas using a paraffin bath. This procedure is commonly utilized in Physical Medicine and Rehabilitation settings to provide therapeutic heat treatment, often for patients experiencing joint pain or stiffness. The typical site of service for this code is an outpatient clinic or therapy department, such as Place of Service 11. The paraffin bath modality is valued for its ability to deliver consistent, soothing heat to targeted areas, supporting improved mobility and comfort for patients undergoing rehabilitation.
Clinical & Coding Specifications
Clinical Context
A patient presents to an outpatient physical therapy clinic with chronic pain in the knees and low back, possibly due to conditions such as fibromyalgia or unspecified joint pain. The physical therapist evaluates the patient and determines that a paraffin bath (CPT 97018) is appropriate to help manage pain and improve joint mobility. The paraffin bath is applied to one or more affected areas, typically hands or feet, as part of a broader rehabilitation plan. The procedure is performed in a therapy department setting, and documentation includes the area treated, duration, and patient response.
Coding Specifications
| Modifier Code | Description | When Used |
|---|---|
| 59 | Distinct Procedural Service | Used when the paraffin bath is performed as a separate and distinct service from other procedures on the same day. |
| 76 | Repeat Procedure by Same Physician | Used when the paraffin bath is repeated by the same provider during the same encounter or on the same day. |
- Associated Provider Taxonomies:
225100000X— Physical Therapist: Represents providers specializing in physical therapy and rehabilitation services.
Related Diagnoses
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M25.50— Pain in unspecified joint- Relevant for patients experiencing joint pain where the specific joint is not identified, often treated with paraffin bath for pain relief.
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M79.7— Fibromyalgia- Paraffin bath may be used to alleviate widespread musculoskeletal pain associated with fibromyalgia.
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M54.5— Low back pain- Paraffin bath can be applied to the low back area to reduce pain and improve mobility.
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M25.561— Pain in right knee- Paraffin bath is suitable for localized pain in the right knee, aiding in pain management and joint function.
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M25.562— Pain in left knee- Paraffin bath is also appropriate for pain in the left knee, supporting rehabilitation and symptom relief.
Related CPT Codes
| CPT Code | Description | Clinical Relationship |
|---|---|---|
97010 | Application of a modality to 1 or more areas; hot or cold packs | Used for thermal therapy; may be used as an alternative or adjunct to paraffin bath. |
97022 | Application of a modality to 1 or more areas; whirlpool | Used for hydrotherapy; can be used in conjunction with or as an alternative to paraffin bath, depending on patient needs. |
- These codes (
97010,97022) are commonly used in physical therapy for pain management and may be billed together with97018if clinically appropriate and distinct.
National Reimbursement Benchmarks
For CPT code 97018, national mean rates show that Medicare reimburses at $6.24, which is notably lower than the BUCA (Blue Cross Blue Shield, UnitedHealth Group, Cigna, Aetna) commercial average of $9.73. Among individual commercial payers, Blue Cross Blue Shield and Cigna offer the highest mean rates at $12.10 and $11.75, respectively, while Aetna is the lowest at $7.26.
Rate dispersion, measured by the difference between the 75th and 25th percentiles, varies significantly across payers. Medicare has the tightest range, with all percentiles at $6.00, indicating no variation. Cigna shows the widest spread, with a difference of $7.17 between its 75th and 25th percentiles. Blue Cross Blue Shield and BUCA also display substantial dispersion, while Aetna and UnitedHealth Group are more moderate.
The table and chart below present a detailed breakdown of national mean rates and percentile distributions for each payer.
State Benchmarks
State: AK1 / 50
Alaska Benchmarks
Alaska exhibits a wide spread in reimbursement rates for CPT code 97018, with Blue Cross Blue Shield showing the largest range between the 25th and 75th percentiles ($24.25 - $11.20 = $13.05), indicating substantial variability in payments. In contrast, Aetna and UnitedHealth Group display minimal rate spread, with all percentiles clustered at or near their mean rates, suggesting consistent reimbursement across providers.
Compared to national averages, Alaska's commercial payers (Aetna, Blue Cross Blue Shield, Cigna, UnitedHealth Group, BUCA) all offer significantly higher mean rates for CPT code 97018. Medicare rates in Alaska are slightly below the national average but remain consistent across percentiles. The table and chart below present the full breakdown of payer-specific rates in Alaska.
Key Insights for Alaska
- Blue Cross Blue Shield is the highest paying payer for CPT 97018 in Alaska, with a mean rate of $18.42.
- Medicare is the lowest paying payer in Alaska, with a mean rate of $6.07, which is slightly below the national Medicare average.
- All commercial payers in Alaska reimburse at rates significantly above their respective national averages, indicating a strong regional premium.
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