ICD-10-CM · Spine

M96.0

M96.0 identifies a failed bony union (pseudarthrosis) at a joint or spinal segment that was intentionally fused through surgical arthrodesis — the fusion simply never consolidated into solid bone.

Verified May 8, 2026 · 5 sources ↓

Status: Billable
Chapter: 13
Related CPT: 15
Region: Spine

Drawn from CDCCMSScoliosis ResearchICDicd10data.com 2026

Documentation tips

What should appear in the chart to support M96.0.

Source · Editorial brief grounded in 5 cited references ↓

Identify the specific prior fusion procedure by date, surgical level(s) or joint, and approach (anterior, posterior, etc.) — payers require a clear causal link between that surgery and the current non-union.
Record imaging findings that confirm non-union: CT scan showing lucency or motion across the fusion mass, lack of bridging trabecular bone, or dynamic flexion-extension radiographs demonstrating persistent segmental motion.
Document the patient's symptoms attributable to the pseudarthrosis (pain, instability, neurologic changes) and distinguish them from adjacent-level pathology so the chart supports M96.0 as the primary driver of the encounter.
Note any contributing factors that impaired fusion — smoking status, osteoporosis, prior radiation, infection, or inadequate immobilization — to establish medical necessity context for revision surgery.
If billing for revision fusion, confirm the operative report explicitly calls out pseudarthrosis as the indication; the diagnosis code must match the documented indication, not just the procedure performed.

Related CPT procedures

Procedure codes commonly billed with M96.0. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

22630 $1,510.72

Posterior interbody arthrodesis of a single lumbar interspace, including laminectomy and/or discectomy performed to prepare the interspace for fusion rather than for decompression.

22612 $1,467.64

Posterior or posterolateral lumbar arthrodesis of a single interspace, performed via a posterior approach with bone graft and typically pedicle screw fixation to achieve vertebral segment fusion.

22600 $1,282.93

Posterior or posterolateral cervical spinal fusion at a single interspace below C2, performed through a posterior approach to achieve bony arthrodesis.

22614 $349.37

Add-on code for each additional interspace treated by posterior or posterolateral arthrodesis beyond the first level billed with a primary fusion code.

22800 $1,312.99

Posterior spinal arthrodesis for deformity correction spanning up to 6 vertebral segments, with or without application of a body cast.

22818 $1,911.87

Kyphectomy involving circumferential spinal exposure and full resection of one or two vertebral segments, including both the vertebral body and posterior elements.

22819 $2,201.79

Kyphectomy with circumferential spinal exposure and full resection of three or more vertebral segments, including vertebral body and posterior elements.

27870 $927.88

Open surgical fusion of the tibiotalar (ankle) joint, performed through a direct incision to prepare joint surfaces and achieve bony union.

28705 $1,106.57

Surgical fusion of all four hindfoot and ankle joints — tibiotalar, subtalar, talonavicular, and calcaneocuboid — performed as a single procedure using internal fixation.

28715 $883.79

Surgical fusion of the three hindfoot joints — subtalar, talonavicular, and calcaneocuboid — performed as a single operative procedure.

28725 $729.14

Surgical fusion of the subtalar joint, eliminating motion between the talus and calcaneus to treat post-traumatic arthritis, degenerative arthritis, or hindfoot deformity.

73562 $42.42

Three-view radiographic examination of the knee joint, capturing anteroposterior, lateral, and a third angle such as a sunrise or oblique view.

72148 $191.72

Non-contrast MRI of the lumbar spine used to evaluate disc pathology, spinal stenosis, nerve root compression, and other structural abnormalities without administration of contrast material.

72141 $190.72

MRI of the cervical spinal canal and its contents performed without contrast material.

77080 View procedure details

Common coding pitfalls

The recurring mistakes coders make with M96.0 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

Assigning M96.0 for fracture nonunion not related to a fusion procedure — fracture nonunion routes through fracture-specific nonunion codes, not M96.0.
Omitting Z98.1 (Arthrodesis status) when the clinical context of the encounter depends on the patient's prior fusion history; M96.0 alone does not communicate the underlying surgical background.
Using M96.0 for hardware failure (broken pedicle screws, rod fracture) without documented non-union — implant complications map to T84-series codes, not M96.0.
Failing to apply M96.0 as a primary diagnosis code when revision fusion is the reason for the encounter; downgrading it to a secondary code misrepresents the clinical picture and can trigger medical necessity denials.
Confusing M96.0 with M96.1 (Postlaminectomy syndrome) — postlaminectomy syndrome is a pain/functional syndrome after decompression, not a fusion failure; the two are distinct and should not be used interchangeably.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

Use M96.0 when a prior fusion or arthrodesis procedure has resulted in a non-union at the intended fusion site — the joint or spinal segment retains abnormal motion rather than achieving solid bony consolidation. The condition is most frequently encountered in spinal surgery (lumbar, cervical, or thoracic fusion failures) but applies equally to peripheral joint arthrodesis of the ankle, wrist, or foot when union fails. The diagnosis requires a documented cause-and-effect relationship between the original fusion procedure and the current non-union; this is a postprocedural complication code, not a standalone degenerative diagnosis.

M96.0 sits in the M96 block ('Intraoperative and postprocedural complications and disorders of musculoskeletal system, not elsewhere classified') and is classified as a disease-category code — it carries no 7th-character extension requirement. For spinal pseudarthrosis, CMS Billing and Coding Article A56396 explicitly lists M96.0 as a diagnosis supporting medical necessity for lumbar spinal fusion (revision), making accurate assignment directly relevant to prior-authorization and reimbursement for revision procedures.

Do not use M96.0 for fracture nonunion unrelated to a prior fusion — that scenario maps through the fracture-specific nonunion codes. Pair M96.0 with Z98.1 (Arthrodesis status) when the prior fusion history is clinically relevant to the current encounter. If the patient has both a pseudarthrosis and adjacent-level degeneration or hardware failure, code each condition separately; M96.0 does not capture implant-related complications.

Sibling codes

Other billable codes under M96 (laterality / anatomic variants).

M96.2

Postradiation kyphosis

M96.3

Postlaminectomy kyphosis

M96.1

Postlaminectomy syndrome, not elsewhere classified

M96.4

Postsurgical lordosis

M96.5

Postradiation scoliosis

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01Does M96.0 require a 7th-character extension?

No. M96.0 is an M-category code classified as a disease, not an injury S-code. No 7th-character extension (A/D/S) applies. The Scoliosis Research Society coding guidance confirms these M96 codes do not require a seventh digit.

02Can M96.0 be used for lumbar pseudarthrosis after interbody fusion?

Yes. CMS Billing and Coding Article A56396 for Lumbar Spinal Fusion explicitly lists M96.0 as a supporting medical necessity diagnosis, making it the correct code for lumbar non-union whether the original fusion was TLIF, PLIF, ALIF, or posterolateral.

03What is the difference between M96.0 and a fracture nonunion code?

M96.0 is specific to failure of an intentional surgical arthrodesis or fusion. Fracture nonunion — where bone fails to heal after a traumatic break — maps to fracture-specific nonunion codes in the S or M80 categories, not to M96.0.

04Should Z98.1 be coded alongside M96.0?

Yes, when the patient's arthrodesis status is relevant to the encounter. Z98.1 communicates the prior fusion history and supports the causal relationship that M96.0 requires. List M96.0 first if pseudarthrosis is the reason for the visit.

05Does M96.0 apply to peripheral joint arthrodesis failures (ankle, wrist, foot)?

Yes. The code is not limited to spinal fusions. Any failed surgical arthrodesis — ankle, subtalar, wrist, finger, or other joint — that results in persistent non-union and abnormal motion qualifies for M96.0, provided the provider documents the causal link to the prior procedure.

06How do I code hardware failure (broken rod or screw) concurrent with pseudarthrosis?

Code both conditions separately. Implant mechanical failure maps to T84-series codes (e.g., T84.216_ for broken internal fixation device of vertebrae). M96.0 covers the non-union itself. Do not use M96.0 to capture the hardware complication.

07Is M96.0 an acceptable primary diagnosis for revision spinal fusion authorization requests?

Yes. When pseudarthrosis is the documented indication for revision surgery, M96.0 should be listed as the primary diagnosis. CMS LCD L37848 for Lumbar Spinal Fusion references M96.0 among the codes that support medical necessity for fusion procedures.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

01CDC ICD-10-CM Tabular List 2026 — code M96.0
02CMS Billing and Coding Article A56396: Lumbar Spinal Fusion — https://www.cms.gov/medicare-coverage-database/view/article.aspx?articleid=56396
03Scoliosis Research Society Coding & Reimbursement Archive: Complications of Spine Surgery in ICD-10 — https://www.srs.org/Education/Coding--Reimbursement
04ICD-10-CM Official Guidelines for Coding and Reporting, Section I.C.16 Documentation of Complications of Care — https://www.cms.gov/Medicare/Coding/ICD10/Downloads/2019-ICD10-Coding-Guidelines-.pdf
05icd10data.com 2026 ICD-10-CM M96.0 — https://www.icd10data.com/ICD10CM/Codes/M00-M99/M96-M96/M96-/M96.0

Mira AI Scribe

Mira AI Scribe captures the prior fusion date, operative level(s) or joint, imaging findings (CT or dynamic X-ray confirming absent bridging bone or persistent motion), and the provider's explicit statement attributing non-union to the prior procedure. That documentation locks in M96.0 as a billable primary diagnosis and prevents downcoding to unspecified postprocedural disorder (M96.89) — an audit flag that delays revision surgery authorizations.

See how Mira captures M96.0 documentation