2026 ICD-10-CM Diagnosis Code M43.6Torticollis

ICD-10-CM Codes›M00–M99›M40-M43›M43

ICD-10-CM M43.6
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M43.6 is a billable ICD-10-CM diagnosis code for torticollis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 551 through 552. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M43.6
Billable Status
Yes — Valid for Submission
Code Describes
Torticollis
Short Description
Torticollis
Same as the full description in the CMS dataset.
Parent Code
M43
Other deforming dorsopathies

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM43Other deforming dorsopathies
This CodeM43.6Torticollis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acquired deformity of neck
  • Acute muscle stiffness of neck
  • Benign paroxysmal torticollis of infancy
  • Cervical spine stiff
  • Decreased range of cervical spine movement
  • Grisel's syndrome
  • Head tilt
  • Intermittent torticollis
  • Paroxysmal dystonia
  • Rheumatic torticollis
  • Sandifer syndrome
  • Stiff back
  • Stiff neck
  • Stiff neck symptom
  • Subluxation of atlantoaxial joint
  • Torticollis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Type 1 Excludes

  • congenital sternomastoid torticollis Q68.0
  • current injury - see Injury, of spine, by body region
  • ocular torticollis R29.891
  • psychogenic torticollis F45.8
  • spasmodic torticollis G24.3
  • torticollis due to birth injury P15.2

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.

    • Disease, diseased
      • Grisel's
    • Grisel's disease
    • Nasopharyngeal
      • torticollis
    • Rheumatic(acute) (subacute)
      • torticollis
    • Torticollis(intermittent) (spastic)
    • Torticollis(intermittent) (spastic)
      • rheumatic

Clinical ClassificationClinical

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

CCSR MUS011
Spondylopathies/spondyloarthropathy (including infective)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Torticollis

    a symptom, not a disease, of a twisted neck. in most instances, the head is tipped toward one side and the chin rotated toward the other. the involuntary muscle contractions in the neck region of patients with torticollis can be due to congenital defects, trauma, inflammation, tumors, and neurological or other factors.

Patient EducationClinical

Neck Injuries and Disorders

Any part of your neck - muscles, bones, joints, tendons, ligaments, or nerves - can cause neck problems. Neck pain is very common. Pain may also come from your shoulder, jaw, head, or upper arms.

Read the full article at MedlinePlus

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

Convert M43.6 to ICD-9-CMHistory

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

ICD-9-CM
723.5 Torticollis NOS
Exact Match The mapping is direct, with no qualifiers.

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 M43.6Overview

Is M43.6 (Other deforming dorsopathies) a billable code?

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

What MS-DRG does M43.6 group to?

When torticollis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 551, 552, with relative weights from 0.9613 to 1.6761 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M43.6?

Under the General Equivalence Mappings, torticollis converts to ICD-9-CM 723.5 (torticollis NOS). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.