2026 ICD-10-CM Diagnosis Code M41.55Other secondary scoliosis, thoracolumbar region

ICD-10-CM Codes›M00–M99›M40-M43›M41

ICD-10-CM M41.55
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M41.55 is a billable ICD-10-CM diagnosis code for other secondary scoliosis, thoracolumbar region. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 456 through 458, 551 through 552. The code is not accepted as a principal diagnosis by the Medicare Code Editor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Scoliosis and other postural dorsopathic deformities.

Code Identity

ICD-10-CM Code
M41.55
Billable Status
Yes — Valid for Submission
Code Describes
Other secondary scoliosis, thoracolumbar region
Short Description
Other secondary scoliosis, thoracolumbar region
Same as the full description in the CMS dataset.
Parent Code
M41.5
Other secondary scoliosis

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM41Scoliosis
This CodeM41.55Other secondary scoliosis, thoracolumbar region

Code EditsBilling

Medicare Code Editor checks that affect claim validity for M41.55.

Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Scoliosis(acquired) (postural)
      • secondary (to) NEC
        • thoracolumbar region

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MUS022
Scoliosis and other postural dorsopathic deformities
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Scoliosis

Scoliosis causes a sideways curve of your backbone, or spine. These curves are often S- or C-shaped. Scoliosis is most common in late childhood and the early teens, when children grow fast. Girls are more likely to have it than boys. It can run in families. Symptoms include leaning to one side and having uneven shoulders and hips.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert M41.55 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
737.43 Scoliosis in oth dis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About M41.55Overview

Is M41.55 (Other secondary scoliosis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other secondary scoliosis, thoracolumbar region on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M41.55 group to?

On inpatient claims, other secondary scoliosis, thoracolumbar region maps to MS-DRG 456, 457, 458, 551, 552, with relative weights from 0.9613 to 8.4034 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M41.55 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because other secondary scoliosis, thoracolumbar region describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

What is the ICD-9 equivalent of M41.55?

Under the General Equivalence Mappings, other secondary scoliosis, thoracolumbar region converts to ICD-9-CM 737.43 (scoliosis in oth dis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.