2026 ICD-10-CM Diagnosis Code M40.203Unspecified kyphosis, cervicothoracic region

ICD-10-CM Codes›M00–M99›M40-M43›M40

ICD-10-CM M40.203
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M40.203 is a billable ICD-10-CM diagnosis code for unspecified kyphosis, cervicothoracic region. 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. Coders also document this condition as cervical kyphosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Scoliosis and other postural dorsopathic deformities.

Code Identity

ICD-10-CM Code
M40.203
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified kyphosis, cervicothoracic region
Short Description
Unspecified kyphosis, cervicothoracic region
Same as the full description in the CMS dataset.
Parent Code
M40.20
Unspecified kyphosis

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM40Kyphosis and lordosis
This CodeM40.203Unspecified kyphosis, cervicothoracic region

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cervical kyphosis
  • Kyphosis of cervicothoracic spine
  • Kyphosis of thoracic spine

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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

Clinical InformationClinical

  • Kyphosis

    deformities of the spine characterized by an exaggerated convexity of the vertebral column. the forward bending of the thoracic region usually is more than 40 degrees. this deformity sometimes is called round back or hunchback.

  • Scheuermann Disease

    a type of juvenile osteochondrosis affecting the fibrocartilaginous disc (intervertebral disc) in the thoracic or thoracolumbar region of the spine. it is characterized by a forward concave spinal curvature or kyphosis.

  • Spine

    the spinal or vertebral column.

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 M40.203 to ICD-9-CMHistory

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

ICD-9-CM
737.10 Kyphosis NOS
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 M40.203Overview

What is the ICD-10 code for unspecified kyphosis, cervicothoracic region?

The ICD-10-CM code for unspecified kyphosis, cervicothoracic region is M40.203 (sometimes written as M40203). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is M40.203 (Unspecified kyphosis) a billable code?

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

What MS-DRG does M40.203 group to?

When unspecified kyphosis, cervicothoracic region 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 M40.203?

Under the General Equivalence Mappings, unspecified kyphosis, cervicothoracic region converts to ICD-9-CM 737.10 (kyphosis NOS). The mapping is approximate, so confirm the match fits the documentation.