Summary & Overview
CPT 20937: Autograft Bone Grafting During Spinal/Orthopedic Surgery
CPT code 20937 denotes intraoperative use of an autograft to fill bony defects — commonly applied during spinal and orthopedic procedures where the surgeon harvests the patient’s own bone through a separate incision and implants it into the defect. This code is important nationally because autograft techniques affect surgical planning, operative time, and resource use, and they carry implications for coverage, billing practices, and quality measurement across payers.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of clinical context for autograft use, typical sites of service, and which stakeholders commonly encounter this code. The publication outlines billing benchmarks, payer coverage patterns, common modifiers, and areas where policy updates or payer-specific rules may affect claims processing. Clinical considerations such as donor-site morbidity and indications for autograft versus alternative graft materials are summarized to provide context for coding decisions.
This summary is intended for a national audience and focuses on how CPT code 20937 integrates into operative billing and payer relationships, offering a foundation for payers, providers, and revenue cycle staff to understand coding application and potential administrative issues.
Billing Code Overview
CPT code 20937 describes the use of an autograft to fill bony defects during a surgical procedure. The provider harvests bone from the patient’s own body through a separate incision and places that autologous bone graft into the defect site as part of the operative repair.
Service type: Autologous bone grafting during surgery
Typical site of service: Inpatient or outpatient surgical setting (operating room)
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with progressive lumbar spinal stenosis and symptomatic spondylolisthesis presents for instrumented posterior spinal fusion. The surgeon plans decompression and fusion from L4 to S1 with placement of pedicle screws and interbody cages. During the procedure, the surgeon harvests an autograft bone (iliac crest) through a separate incision to augment fusion and fill bony defects. The workflow includes preoperative localization and consent, general anesthesia, prone positioning, a primary posterior midline incision for decompression and instrumentation, a separate posterior-lateral incision over the iliac crest for autograft harvest, graft preparation and placement into posterolateral gutters and interbody spaces, hemostasis, layered closure of both donor and recipient sites, and immediate postoperative monitoring in the PACU with routine wound checks and discharge planning.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
22 | Increased procedural services | Use when work, time, or technical difficulty significantly exceeds usual for 20937 (document rationale). |
23 | Unusual anesthesia | Use when general anesthesia is not used due to patient condition but procedure is still medically necessary and more intensive than local anesthesia. |
50 | Bilateral procedure | Use when bilateral autograft harvests or bilateral surgical sites are performed and the payer requires a bilateral modifier. |
52 | Reduced services | Use when the autograft harvest or grafting is partially performed or incomplete. |
53 | Discontinued procedure | Use when the autograft harvest is started but halted for documented medical reasons. |
59 | Distinct procedural service | Use when the autograft harvest is a separate incision/site and distinct from the primary spinal procedure to indicate separate service. |
62 | Two surgeons | Use when two surgeons are required and both actively perform portions of the autograft harvest or grafting. |
63 | Procedure performed on infants less than 4 kg | Rare for this code; use when applicable per payer rules. |
66 | Surgical team (when applicable) | Use when a surgical team approach is documented for complex reconstruction requiring 20937 grafting. |
78 | Unplanned return to OR following initial procedure | Use when reoperation for graft-related complication occurs during global period. |
80 | Assistant surgeon | Use when an assistant surgeon is documented assisting with harvest or graft placement. |
81 | Minimum assistant surgeon | Use when minimal assistance is documented per payer rules. |
82 | Assistant surgeon (when qualified resident not available) | Use when no qualified resident is available and an assistant surgeon performs duties. |
AS | Physician assistant, nurse practitioner, or clinical nurse specialist | Use when an advanced practice provider bills as assistant or performs billable portions per state law and payer policy. |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
2084P0805X | Orthopedic Spine Surgery | Orthopedic surgeons who perform spinal fusion and autograft harvests. |
207RH0002X | Neurosurgery | Neurosurgeons performing complex spine procedures with autograft use. |
207L00000X | General Surgery (Spine-focused) | Surgeons with experience in spinal reconstruction and grafting. |
364S00000X | Physical Medicine & Rehabilitation | Often involved in perioperative rehabilitation planning for fusion patients. |
2085P0202X | Pain Medicine | Specialists managing perioperative pain and opioid-sparing strategies. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
M48.06 | Spinal stenosis, lumbar region | Common indication for decompression and fusion where autograft 20937 augments fusion. |
M43.16 | Spondylolisthesis, lumbar region | Instability requiring fusion and use of autograft to promote bony union. |
M51.27 | Other intervertebral disc disorders with radiculopathy, lumbosacral region | Disc disease leading to surgical fusion and grafting. |
M54.16 | Radiculopathy, lumbar region | Symptom complex prompting surgical intervention with fusion and autograft. |
M96.1 | Postlaminectomy syndrome, not elsewhere classified | Revision or complex cases where autograft may be required to address bony defects. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
22612 | Arthrodesis, posterior or posterolateral technique, single level; lumbar | Common primary fusion technique performed alongside autograft placement for posterolateral fusion. |
22630 | Arthrodesis, posterior interbody technique, including laminectomy and fusion, single interspace; lumbar | Interbody fusion often performed with autograft packed into the interbody space. |
22842 | Posterior segmental instrumentation (e.g., pedicle fixation), 3 to 6 vertebral segments | Instrumentation code typically reported for hardware placed during the fusion procedure where autograft is used to promote fusion. |
20936 | Autograft, any donor site, morselized (includes local bone) | Related autograft code for morselized graft material; may be used when different graft preparation is performed. |
27096 | Bone graft, proximal tibia or other sites (add-on) — (example) | Codes for alternative donor sites; used when autograft is harvested from a site other than iliac crest (payer-specific applicability). |