2026 ICD-10-CM Diagnosis Code M46.05Spinal enthesopathy, thoracolumbar region

ICD-10-CM Codes›M00–M99›M45-M49›M46

ICD-10-CM M46.05
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M46.05 is a billable ICD-10-CM diagnosis code for spinal enthesopathy, thoracolumbar 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 spinal enthesopathy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M46.05
Billable Status
Yes — Valid for Submission
Code Describes
Spinal enthesopathy, thoracolumbar region
Short Description
Spinal enthesopathy, thoracolumbar region
Same as the full description in the CMS dataset.
Parent Code
M46.0
Spinal enthesopathy

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM45-M49Spondylopathies
CategoryM46Other inflammatory spondylopathies
This CodeM46.05Spinal enthesopathy, thoracolumbar region

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Spinal enthesopathy
  • Spinal enthesopathy of lumbar region
  • Spinal enthesopathy of thoracic region
  • Spinal enthesopathy of thoracolumbar region

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.

    • Enthesopathy(peripheral)
      • spinal
        • thoracolumbar region

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

Patient EducationClinical

Connective Tissue Disorders

Your connective tissue supports many different parts of your body, such as your skin, eyes, and heart. It is like a "cellular glue" that gives your body parts their shape and helps keep them strong. It also helps some of your tissues do their work. It is made of many kinds of proteins. Cartilage and fat are types of connective tissue.

Read the full article at MedlinePlus

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

Convert M46.05 to ICD-9-CMHistory

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

ICD-9-CM
720.1 Spinal enthesopathy
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 M46.05Overview

Is M46.05 (Spinal enthesopathy) a billable code?

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

What MS-DRG does M46.05 group to?

When spinal enthesopathy, thoracolumbar 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 M46.05?

Under the General Equivalence Mappings, spinal enthesopathy, thoracolumbar region converts to ICD-9-CM 720.1 (spinal enthesopathy). 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.