2027 ICD-10-CM Diagnosis Code M62.5A9Muscle wasting and atrophy, not elsewhere classified, back, unspecified level

ICD-10-CM Codes›M00–M99›M60-M63›M62

ICD-10-CM M62.5A9
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M62.5A9 is a billable ICD-10-CM diagnosis code for muscle wasting and atrophy, not elsewhere classified, back, unspecified level. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 557 through 558. Coders also document this condition as atrophy of muscle of back. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Muscle disorders.

Code Identity

ICD-10-CM Code
M62.5A9
Billable Status
Yes — Valid for Submission
Code Describes
Muscle wasting and atrophy, not elsewhere classified, back, unspecified level
Short Description
Muscle wasting and atrophy, NEC, back, unspecified level
Parent Code
M62.5A
Muscle wasting and atrophy, not elsewhere classified, back

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM60-M63Disorders of muscles
CategoryM62Other disorders of muscle
This CodeM62.5A9Muscle wasting and atrophy, not elsewhere classified, back, unspecified level

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Atrophy of muscle of back

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M62.5A9: its own notes plus those printed at M62.5, M62, block M60-M63, and Chapter 13. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From M62.5 Muscle wasting and atrophy, not elsewhere classified applies to 28 codes
From M62 Other disorders of muscle applies to 131 codes
From Block M60-M63 Disorders of muscles applies to 420 codes
  • dermatopolymyositis (M33.-)
  • myopathy in amyloidosis (E85.-)
  • myopathy in polyarteritis nodosa (M30.0)
  • myopathy in rheumatoid arthritis (M05.32)
  • myopathy in scleroderma (M34.-)
  • myopathy in Sjögren's syndrome (M35.03)
  • myopathy in systemic lupus erythematosus (M32.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From M62.5 Muscle wasting and atrophy, not elsewhere classified applies to 28 codes
  • pelvic muscle wasting (N81.84)
From M62 Other disorders of muscle applies to 131 codes
  • nontraumatic hematoma of muscle (M79.81)
From Block M60-M63 Disorders of muscles applies to 420 codes
  • muscular dystrophies and myopathies (G71-G72)
From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Notes

General instructions on how these codes are used.

From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

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 MUS026
Muscle disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement M62.5A9 replaces the following previously assigned code(s):

  • M62.58 - Muscle wasting and atrophy, NEC, oth site
FY 2023AddedAdded to the ICD-10-CM code setEffective October 1, 2022.
FY 2024–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M62.5A9Overview

Is M62.5A9 (Muscle wasting and atrophy, not elsewhere classified, back) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report muscle wasting and atrophy, not elsewhere classified, back, unspecified level on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M62.5A9 group to?

When muscle wasting and atrophy, not elsewhere classified, back, unspecified level is the principal diagnosis on an inpatient stay, it groups to MS-DRG 557, 558, with relative weights from 0.8873 to 1.4883 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M62.5A9 be reported with G54.5?

Not as a rule. The Excludes1 note at M62.5, which applies to M62.5A9, lists "neuralgic amyotrophy (G54.5)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).