ICD-10-CM · Spine

M41.26

M41.26 identifies idiopathic scoliosis of the lumbar spine that does not fall under the juvenile (M41.116) or adolescent (M41.126) subcategories — capturing adult-onset or otherwise unclassified idiopathic lumbar curvature with a Cobb angle ≥10°.

Verified May 8, 2026 · 6 sources ↓

Status: Billable
Chapter: 13
Related CPT: 14
Region: Spine

Drawn from CDCICD10DataCMSAAPCClear-institute

Documentation tips

What should appear in the chart to support M41.26.

Source · Editorial brief grounded in 6 cited references ↓

Record the Cobb angle measured on standing AP or PA lumbar radiograph — the threshold for scoliosis diagnosis is ≥10°; document the specific measurement, not just 'scoliosis present.'
Specify that the etiology is idiopathic — explicitly rule out neuromuscular, congenital, thoracogenic, or secondary (degenerative) causes in the clinical note to justify M41.26 over alternative M41 subcategories.
Identify the primary curve apex or region as lumbar (L1–L5) to support the '6' regional digit; if the apex is at the thoracolumbar junction (T10–L1), M41.25 is the correct code.
Document the patient's current age and, when relevant, age at diagnosis — this distinguishes M41.26 (adult or unclassified) from juvenile (M41.116) and adolescent (M41.126) subtypes.
For surgical cases, document prior conservative management (physical therapy, bracing, analgesics) and its outcomes to satisfy medical necessity requirements for lumbar fusion or instrumented correction.

Related CPT procedures

Procedure codes commonly billed with M41.26. Linking the right diagnosis to the right procedure is what establishes medical necessity.

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

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.

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.

22800 $1,312.99

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

22802 $1,936.25

Posterior spinal arthrodesis for deformity correction spanning 7 to 12 vertebral segments, with or without body cast application.

22804 $2,222.50

Posterior spinal arthrodesis for deformity correction spanning 13 or more vertebral segments, performed with or without application of a body cast.

72100 $40.42

Radiologic examination of the lumbosacral spine capturing two or three views, used to evaluate the lumbar vertebrae and sacrum for injury, degeneration, or structural abnormality.

72110 $53.44

Radiologic examination of the lumbar spine (lumbosacral) with a minimum of four views, including oblique and/or bending views.

72114 $61.79

Radiologic examination of the lumbosacral spine, complete series with bending (flexion/extension) views — minimum of 6 views total.

72120 $42.09

Radiologic examination of the lumbosacral spine using bending views only, minimum of four views, to assess spinal flexibility and alignment.

97110 $29.06

Therapeutic exercise billed per 15-minute unit, targeting strength, endurance, range of motion, or flexibility with direct one-on-one patient contact.

20937 $147.30

Add-on code for harvesting and using morselized autograft bone in spine surgery via a separate skin or fascial incision.

20938 $163.33

Structural autograft harvested from the patient during a spinal procedure, reported as an add-on to the primary spine surgery code.

97530 View procedure details

20936 View procedure details

Common coding pitfalls

The recurring mistakes coders make with M41.26 and adjacent codes.

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

Using M41.26 for degenerative scoliosis in an older adult: if imaging shows disc space narrowing, osteophytes, or lateral listhesis as the driver of curvature, M41.56 (other secondary scoliosis, lumbar region) is more accurate than M41.26.
Defaulting to M41.20 (site unspecified) when imaging clearly shows a lumbar apex — M41.26 is the billable, specific code and payers may flag M41.20 for lacking specificity.
Confusing the lumbar region code (M41.26) with the lumbosacral code (M41.27) — if the curve's primary region or apex extends to L5–S1 or the sacrum, M41.27 applies.
Assigning M41.26 when the patient meets age criteria for adolescent idiopathic scoliosis (10–17 years) — use M41.126 in that scenario; M41.26 is not age-appropriate for adolescent patients.
Omitting additional codes for associated conditions such as lumbar radiculopathy or stenosis that may coexist with scoliosis — a 'Code Also' logic applies when these are separately documented and clinically relevant.

Clinical context

Source · Editorial summary grounded in 6 cited references ↓

M41.26 sits within the M41.2 'Other idiopathic scoliosis' subcategory and is the lumbar-region-specific code. Use it when the treating provider has documented idiopathic scoliosis of the lumbar spine and the patient's age or clinical presentation does not qualify as juvenile (ages 5–9, M41.116) or adolescent (ages 10–17, M41.126). It frequently applies to adult idiopathic scoliosis discovered or progressing in adulthood, where no congenital, neuromuscular, or secondary cause has been identified.

Do not use M41.26 for degenerative (de novo) scoliosis that arose from disc and facet degeneration — that pattern is better captured under M41.56 (other secondary scoliosis, lumbar region) or the appropriate secondary scoliosis code when a clear etiology exists. Likewise, if the curve spans the thoracolumbar junction as the primary region, M41.25 is correct; if it extends into the lumbosacral region, use M41.27. Only use M41.20 (site unspecified) when imaging fails to define the apex or primary curve region.

M41.26 is listed by CMS as a supporting diagnosis for lumbar spinal fusion medical necessity (LCD A56396). If surgical intervention is being pursued, confirm that documentation establishes curve magnitude, symptom burden, and failure of conservative management — payers will scrutinize these elements during prior authorization and post-payment audit.

Sibling codes

Other billable codes under M41.2 (laterality / anatomic variants).

M41.27

Other idiopathic scoliosis, lumbosacral region

M41.24

Other idiopathic scoliosis, thoracic region

M41.23

Other idiopathic scoliosis, cervicothoracic region

M41.25

Other idiopathic scoliosis, thoracolumbar region

M41.20

Other idiopathic scoliosis, site unspecified

M41.22

Other idiopathic scoliosis, cervical region

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01When does M41.26 apply instead of M41.126 for a lumbar scoliosis patient?

M41.126 is reserved for adolescent idiopathic scoliosis in patients aged 10–17. Once a patient ages out of that window, or if onset/diagnosis occurred in adulthood without a prior adolescent classification, M41.26 is correct.

02Can M41.26 be used for degenerative scoliosis in a 65-year-old?

Only if the provider explicitly documents the scoliosis as idiopathic with no degenerative driver. If imaging shows disc degeneration, osteophytes, or lateral listhesis as the cause, M41.56 (other secondary scoliosis, lumbar region) is the more accurate code.

03Does M41.26 support medical necessity for lumbar spinal fusion?

Yes. CMS LCD A56396 (Billing and Coding: Lumbar Spinal Fusion) lists M41.26 as a supporting diagnosis. However, documentation must still establish curve severity, neurological compromise or functional limitation, and failure of conservative care.

04What is the minimum Cobb angle needed to assign M41.26?

A Cobb angle ≥10° on standing radiograph is the accepted clinical threshold to diagnose scoliosis. Values below 10° do not meet the definition and should not be coded as scoliosis.

05Should I use M41.26 or M41.27 when the lumbar curve extends to the lumbosacral level?

Use M41.27 when the primary curve region or apex is at the lumbosacral junction (L5–S1/sacrum). Use M41.26 when the curve is confined to or primarily involves L1–L5.

06Can M41.26 be coded alongside radiculopathy or lumbar stenosis?

Yes. Scoliosis can coexist with radiculopathy (M54.16–M54.17) or spinal stenosis (M48.06–M48.07). Code both when each is separately documented and clinically addressed during the encounter; sequencing depends on the reason for the visit.

07Is M41.26 valid for inpatient and outpatient claims?

Yes. M41.26 is a fully billable, specific ICD-10-CM code effective October 1, 2025 (FY2026) and is valid for all HIPAA-covered transactions in both inpatient and outpatient settings.

Sources & references

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

01CDC ICD-10-CM Tabular List 2026 (effective Oct 1, 2025)
02
icd10data.com
https://www.icd10data.com/ICD10CM/Codes/M00-M99/M40-M43/M41-/M41.26
03
cms.gov
https://www.cms.gov/medicare-coverage-database/view/article.aspx?articleid=56396
04
aapc.com
https://www.aapc.com/codes/icd-10-codes/M41.26
05
clear-institute.org
https://clear-institute.org/blog/icd-10-coding-for-scoliosis/
06
icdcodes.ai
https://icdcodes.ai/diagnosis/degenerative-scoliosis/documentation

Mira AI Scribe

Mira AI Scribe captures the Cobb angle measurement from standing lumbar X-ray, the provider's documented etiology (idiopathic, ruling out neuromuscular or degenerative causes), the primary curve apex location (lumbar L1–L5), and the patient's age at diagnosis. This prevents downcoding to unspecified M41.20, misclassification as adolescent or degenerative scoliosis, and missing the specificity payers require for spinal fusion medical necessity review.

See how Mira captures M41.26 documentation