Summary & Overview
CPT 27324: Open Deep Soft-Tissue Biopsy of Thigh or Knee
CPT code 27324 designates an open biopsy of deep soft tissue in the thigh or knee, where tissue from below the fascia or within muscle is removed and submitted for laboratory analysis. This code captures a diagnostic surgical procedure used to evaluate suspicious masses or lesions in deep lower-extremity soft tissues. It matters nationally because timely and accurate tissue diagnosis can affect oncologic staging, infection management, and surgical planning, and because surgical biopsy services drive hospital and ambulatory surgery center utilization.
Key payers addressed in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of clinical context for 27324, typical sites of service, and common billing considerations. The full analysis presents benchmark payment levels, payer-specific coverage highlights where available, and policy or coding guidance updates that affect billing and claims adjudication. The material also outlines documentation elements associated with surgical deep-tissue biopsies and situates 27324 among related procedural codes for musculoskeletal and soft-tissue diagnostic services.
Data not available in the input is noted where payer-specific rates, associated taxonomies, ICD-10 diagnoses, and related codes would normally appear.
Billing Code Overview
CPT code 27324 describes an open biopsy procedure in which the provider removes a sample of suspicious tissue from below the fascia or within the muscle of the thigh or knee and submits the specimen to a laboratory for analysis to determine its nature. This is a surgical biopsy of deep soft tissue (thigh or knee musculature) intended to obtain diagnostic tissue for histopathologic or microbiologic examination.
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Service type: Surgical biopsy (open deep soft tissue biopsy)
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Typical site of service: Hospital operating room, ambulatory surgery center, or other surgical suite for deep soft-tissue procedures
Clinical & Coding Specifications
Clinical Context
A 52-year-old patient presents to an orthopedic clinic with a progressively enlarging, painful mass deep in the anterior thigh that became more prominent over several weeks. The orthopedic surgeon obtains MRI imaging demonstrating a 4.5 cm intramuscular lesion suspicious for sarcoma versus benign soft-tissue tumor. After discussion in multidisciplinary conference, the patient is scheduled for an image-guided open core biopsy performed in the ambulatory surgery center. Under general or regional anesthesia the surgeon makes a small incision, dissects down through subcutaneous tissue and fascia, and obtains multiple core tissue samples from within the muscle for submission to anatomic pathology and microbiology as indicated. Hemostasis is achieved, the wound is irrigated and closed, and the specimen is sent fresh and in formalin for histologic, immunohistochemical, and molecular testing. Typical site of service is an ambulatory surgery center or hospital outpatient department. The service type is a deep (below fascia) or intramuscular biopsy of the thigh/knee with specimen submission for laboratory analysis. Typical clinical workflow includes preoperative imaging review, informed consent, sterile biopsy procedure, specimen labeling and routing to laboratory, and postoperative wound care and pathology follow-up.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
11 | Provider performed the service as usual (normal service) | Use for standard, uncomplicated performance of the biopsy when no unusual circumstances apply. |