M41.27 classifies idiopathic scoliosis of the lumbosacral region that does not fit the defined subtypes of infantile, juvenile, or adolescent idiopathic scoliosis — specifically when the curve apex or primary structural involvement is at the lumbosacral junction (L4–S1 segment).
Verified May 8, 2026 · 5 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 12
- Region
- Spine
Documentation tips
What should appear in the chart to support M41.27.
Source · Editorial brief grounded in 5 cited references ↓
- Document the age at which scoliosis was first diagnosed — not the patient's current age — to justify 'other idiopathic' vs. adolescent idiopathic classification.
- Specify lumbosacral region by name or describe the curve apex at the L5–S1 level; 'lumbar' alone routes to M41.26, not M41.27.
- Record Cobb angle measured on full-length standing PA radiograph; include the end vertebrae used for measurement to support medical necessity for bracing, PT, or surgical workup.
- Document curve direction (dextroscoliosis or levoscoliosis) and any associated rotation, even though these descriptors don't change the ICD-10 code — payers and prior auth reviewers require them.
- If post-operative, add Z98.1 (arthrodesis status) alongside M41.27 to reflect prior fusion and support DRG assignment under MS-DRG 456–458.
- When multiple curves are present, identify the primary structural curve and secondary compensatory curve separately; code each region involved.
Related CPT procedures
Procedure codes commonly billed with M41.27. Linking the right diagnosis to the right procedure is what establishes medical necessity.
Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis
Common coding pitfalls
The recurring mistakes coders make with M41.27 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Using M41.27 for a patient whose scoliosis was diagnosed in adolescence — that maps to M41.17 (adolescent idiopathic scoliosis, lumbosacral region), not M41.27, regardless of the patient's current age.
- Conflating 'lumbar' and 'lumbosacral' — M41.26 covers the lumbar region; M41.27 is strictly for curves centered at the lumbosacral junction. Using M41.26 when documentation clearly states lumbosacral will undercode specificity.
- Defaulting to M41.27 for degenerative or de novo adult scoliosis with an identified secondary cause — if a cause is documented (e.g., disc degeneration, leg length discrepancy, neuromuscular disease), a secondary scoliosis code (M41.5x, M41.4x) or M41.87 may be more accurate.
- Failing to code all involved spinal regions for multi-curve presentations — ICD-10-CM allows and expects multiple codes when curves span more than one region.
- Assigning M41.9 (scoliosis, unspecified) when the provider has documented region and idiopathic etiology — M41.27 is available and required for specificity.
Clinical context
Source · Editorial summary grounded in 5 cited references ↓
Use M41.27 when the provider documents idiopathic scoliosis with primary involvement of the lumbosacral region and the etiology is unknown but does not fall under the age-defined adolescent idiopathic scoliosis category (M41.17) or infantile/juvenile subtypes. The 'other idiopathic' designation under M41.2 typically captures adult-onset idiopathic scoliosis or cases where the age at diagnosis was not recorded during a defined developmental window.
The lumbosacral region specificity (7th character logic aside — the 6th character '7' here encodes the region) is critical: if the curve apex is in the lumbar spine proper, use M41.26 instead. M41.27 is reserved for curves centered at or across the L5–S1 level. For multi-region curves, assign codes for each involved region per official ICD-10-CM guidance, leading with the primary structural curve.
Note that scoliosis classification in ICD-10-CM is based on age at diagnosis, not age at presentation. A 55-year-old presenting with a curve first diagnosed in adolescence codes to the adolescent idiopathic category (M41.17 for lumbosacral). M41.27 applies when the idiopathic curve was first identified in adulthood or when the onset timing is undocumented and the presentation does not align with a developmental subtype. If the scoliosis is secondary to a neuromuscular disorder, degenerative process, or trauma, do not use M41.27 — use the appropriate M41.4x, M41.5x, or M41.8x code.
Sibling codes
Other billable codes under M41.2 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 5 cited references ↓
01What is the difference between M41.26 and M41.27?
02Can I use M41.27 for an adult patient whose scoliosis was first diagnosed in their teens?
03When does 'other idiopathic' apply versus adolescent idiopathic scoliosis at the lumbosacral level?
04Should I code M41.27 for degenerative adult scoliosis presenting at the lumbosacral level?
05What DRGs are associated with M41.27?
06Do I need a 7th character for M41.27?
07If a patient has both a thoracic and a lumbosacral curve, should I use one code or two?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CDC ICD-10-CM Tabular List 2026, effective October 1, 2025
- 02icd10data.comhttps://www.icd10data.com/ICD10CM/Codes/M00-M99/M40-M43/M41-/M41.27
- 03aapc.comhttps://www.aapc.com/codes/icd-10-codes/M41.27
- 04cms.govhttps://www.cms.gov/files/document/fy-2025-icd-10-cm-coding-guidelines.pdf
- 05clear-institute.orghttps://clear-institute.org/blog/icd-10-coding-for-scoliosis/
Mira AI Scribe
The Mira AI Scribe captures the age at first diagnosis, curve apex location (lumbosacral junction vs. lumbar proper), Cobb angle with end vertebrae, curve direction, Risser grade if applicable, and any prior treatment or surgical history. This prevents defaulting to M41.26 (lumbar) or M41.9 (unspecified) when lumbosacral-specific documentation exists, and ensures the encounter record supports DRG assignment and payer medical necessity review.
See how Mira captures M41.27 documentation