Summary & Overview

HCPCS S2351: Anterior Lumbar Diskectomy, Additional Interspace

HCPCS Level II code S2351 represents an add-on billing entry for an anterior lumbar diskectomy with decompression of the spinal cord and/or nerve root(s), including osteophytectomy, billed for each additional interspace beyond the primary procedure. This code is relevant to hospitals, ambulatory surgery centers, spine surgeons, and payers managing coverage and payment for complex lumbar decompression procedures. Nationally, lumbar spine surgeries constitute a significant portion of spine procedural volume and spending; accurate use of add-on codes like S2351 affects claim adjudication, bundling decisions, and payment accuracy.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise outline of the clinical procedure and typical sites of service, an explanation of where S2351 fits relative to the primary anterior diskectomy code, and the practical implications for billing and coding workflows. The publication also highlights benchmarks and policy-relevant topics readers should expect: coding hierarchy for primary versus additional interspaces, common billing modifiers and their roles (listed separately), and payer-specific program considerations where available.

Data not available in the input: associated taxonomies, ICD-10 diagnoses, related codes, and service-line financial benchmarks are not provided in the source content.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareS2351HCPCS Level IIspine surgerydiskectomylumbar decompressionadd-on codesurgical billingambulatory surgery centerhospital inpatient

Billing Code Overview

HCPCS Level II code S2351 describes an anterior lumbar diskectomy with decompression of the spinal cord and/or nerve root(s), including osteophytectomy, billed for each additional interspace. This is an add-on surgical procedure code reported when the primary anterior lumbar diskectomy procedure has already been billed and one or more additional lumbar interspaces required decompression during the same operative session.

Service Type: Surgical — spinal decompression / diskectomy (add-on)

Typical Site of Service: Hospital inpatient or outpatient surgical center; ambulatory surgery center, depending on clinical indication and payer policies.

Clinical & Coding Specifications

Clinical Context

A 56-year-old patient presents with progressive left-sided radicular leg pain, neurogenic claudication, and objective neurologic deficits after failing conservative care (physical therapy, epidural steroid injections, and medication management) for six months. MRI demonstrates a central and left paracentral lumbar disc herniation with foraminal narrowing and nerve-root compression at L4–L5 and a smaller symptomatic disc extrusion at L5–S1. The spine surgeon schedules an anterior diskectomy with decompression of the spinal cord and/or nerve root(s), including osteophytectomy, billing one primary procedure for the first interspace and S2351 for each additional lumbar interspace treated.

Clinical workflow:

Preoperative evaluation in the outpatient spine clinic with imaging review, neuromonitoring planning, anesthesia assessment, and medical optimization.
On the day of surgery in an ambulatory surgery center or hospital operating room, the patient receives general anesthesia; positioning and fluoroscopic localization are performed.
The surgical team performs an anterior approach diskectomy and decompression at the primary lumbar level with osteophytectomy as indicated; S2351 is reported for each additional lumbar interspace addressed during the same operative session in addition to the primary procedure code.
Intraoperative neuromonitoring and implant or graft placement occur as clinically indicated.
Postoperative recovery in PACU with standard discharge criteria for same-day discharge from an ambulatory surgery center or transfer to an inpatient ward for observation if medically required.
Postoperative follow-up in the spine clinic, wound checks, and staged rehabilitation as appropriate.

Coding Specifications

Modifier	Description	When to Use
`59`	Distinct Procedural Service	When a separate and distinct procedure or service not normally reported together is performed at a different interspace or anatomic site during the same session.
`62`	Two Surgeons	When two surgeons work together as primary surgeons performing distinct parts of the procedure.
`66`	Surgical Team	When a surgical team approach is used for complex cases requiring multiple surgeons.
`76`	Repeat Procedure by Same Physician	If the same surgeon repeats the diskectomy procedure later the same day.
`77`	Repeat Procedure by Another Physician	If a different surgeon repeats the procedure later the same day.
`50`	Bilateral Procedure	When a bilateral procedure modifier is required; rarely applicable but used when bilateral lumbar approaches are reported.
`22`	Increased Procedural Services	When work is substantially greater than typical for the procedure (extensive scarring, unexpected complexity).
`52`	Reduced Services	When the procedure is partially reduced or not completed as documented.
`53`	Discontinued Procedure	When the procedure is started but discontinued due to extenuating circumstances.
`59`	Distinct Procedural Service	When an additional interspace is coded separately from the primary procedure (used in tandem with `S2351`).
`91`	Repeat Clinical Diagnostic Laboratory Test	When repeat intraoperative laboratory testing is performed and must be reported.
`AS`	Physician Assistant/Advanced Practice Clinician Surgical Assist	When a PA or APN provides surgical assist services under applicable rules.
`QX`	CRNA Service With Non-Physician Anesthetist Absence of Medical Direction	When a certified registered nurse anesthetist performs anesthesia without medical direction by an MD/DO.

Taxonomy Code	Specialty	Notes
`2086S0102X`	Spine Surgery (Orthopaedic Spine)	Orthopaedic surgeons who specialize in spinal procedures, commonly perform anterior discectomy/decompression.
`207XS0101X`	Neurological Surgery	Neurosurgeons who perform surgical decompression, discectomy, and osteophytectomy.
`367A00000X`	Physical Medicine & Rehabilitation	PM&R physicians involved in preoperative and postoperative functional management and rehabilitation.
`2084P0800X`	Pain Medicine	Pain management specialists who provide preoperative injections and nonsurgical care; may co-manage spine patients.
`174400000X`	Anesthesiology	Anesthesiologists who provide general anesthesia and intraoperative pain management.

ICD-10 Code	Description	Clinical Relevance
`M51.26`	Other intervertebral disc displacement, lumbar region	Lumbar disc displacement causing nerve-root compression amenable to diskectomy and decompression.
`M51.27`	Other intervertebral disc displacement, lumbosacral region	Disc displacement at L5–S1 causing radiculopathy treated with diskectomy and decompression.
`M54.16`	Radiculopathy, lumbar region	Clinical presentation of nerve root irritation or compression prompting surgical decompression.
`M48.06`	Spinal stenosis, lumbar region	Central or lateral recess stenosis contributing to neurogenic claudication treated with decompression.
`M47.26`	Other spondylosis with radiculopathy, lumbar region	Degenerative osteophytes and spondylotic changes that may require osteophytectomy with diskectomy.

CPT Code	Description	Relationship to This Procedure
`22558`	Arthrodesis, posterior or posterolateral technique, single level; lumbar	Commonly performed in the same operative episode when fusion is indicated for instability following discectomy or wide decompression.
`63030`	Laminotomy (hemilaminectomy), with decompression of nerve root(s), including partial facetectomy, foraminotomy and/or excision of herniated intervertebral disc, 1 interspace, lumbar	Performed when posterior decompression is chosen or when additional posterior-level decompression is required during the same hospitalization.
`22585`	Arthrodesis, combined posterior or posterolateral technique with posterior interbody technique, single level; lumbar	Used when an interbody fusion is performed in conjunction with discectomy for degenerative instability.
`20931`	Allograft, structural, for spine surgery when used	Reported when structural allograft material is implanted during lumbar fusion performed alongside discectomy.
`95940`	Motor and sensory nerve conduction studies; 1-2 studies	Performed intraoperatively or pre/postoperatively for neuromonitoring or diagnostic evaluation of radiculopathy.

OpenPayer