2027 ICD-10-CM Diagnosis Code M85.10Skeletal fluorosis, unspecified site
ICD-10-CM Codes›M00–M99›M80-M85›M85
- Billable — Valid for Submission
- Chronic Condition
M85.10 is a billable ICD-10-CM diagnosis code for skeletal fluorosis, unspecified site. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 564 through 566. Coders also document this condition as myelopathy due to fluorosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified bone disease and musculoskeletal deformities.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Myelopathy due to fluorosis
- Skeletal fluorosis
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to M85.10: its own notes plus those printed at M85 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.
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.
- 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.
- 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
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Convert M85.10 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M85.10Overview
What is the ICD-10 code for skeletal fluorosis, unspecified site?
The ICD-10-CM code for skeletal fluorosis, unspecified site is M85.10 (sometimes written as M8510). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is M85.10 (Skeletal fluorosis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report skeletal fluorosis, unspecified site on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does M85.10 group to?
When skeletal fluorosis, unspecified site is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 566, 565, with relative weights from 0.7374 to 1.4909 depending on complications. Higher weights mean higher Medicare reimbursement.
Can M85.10 be reported with Q78.0?
Not as a rule. The Excludes1 note at M85, which applies to M85.10, lists "osteogenesis imperfecta (Q78.0)". 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).
What is the ICD-9 equivalent of M85.10?
Under the General Equivalence Mappings, skeletal fluorosis, unspecified site converts to ICD-9-CM 733.99 (bone & cartilage dis NEC). The mapping is approximate, so confirm the match fits the documentation.
