M85.13 – Skeletal fluorosis, forearm

ICD-10-CM 2027 diagnosis code · Disorders of bone density and structure

Non-billable header

ICD-10-CM code M85.13

Code: M85.13 (claims format: M8513)
Description: Skeletal fluorosis, forearm
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
Block: M80-M85 Disorders of bone density and structure
Parent codes: M85 › M85.1

Billable codes under M85.13

M85.13 is a header code and cannot be used on claims. Choose the most specific code:

M85.131 – Skeletal fluorosis, right forearmBillable
M85.132 – Skeletal fluorosis, left forearmBillable
M85.139 – Skeletal fluorosis, unspecified forearmBillable

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

M85 – Other disorders of bone density and structure

Excludes1 (not coded here):

osteogenesis imperfecta (Q78.0)
osteopetrosis (Q78.2)
osteopoikilosis (Q78.8)
polyostotic fibrous dysplasia (Q78.1)

Index terms for M85.13

Entries in the ICD-10-CM alphabetic index that lead to this code:

Fluorosis, skeletal, forearm

Related codes in M85.1

M85.10 – Skeletal fluorosis, unspecified siteBillable
M85.11 – Skeletal fluorosis, shoulderHeader
M85.12 – Skeletal fluorosis, upper armHeader
M85.14 – Skeletal fluorosis, handHeader
M85.15 – Skeletal fluorosis, thighHeader
M85.16 – Skeletal fluorosis, lower legHeader
M85.17 – Skeletal fluorosis, ankle and footHeader
M85.18 – Skeletal fluorosis, other siteBillable
M85.19 – Skeletal fluorosis, multiple sitesBillable

Frequently asked questions

What is ICD-10 code M85.13?

M85.13 is the ICD-10-CM code for skeletal fluorosis, forearm, in the block M80-M85 (Disorders of bone density and structure).

Is M85.13 a billable code?

No. M85.13 is a header code with more specific child codes; report one of the billable codes listed above.

What category does M85.13 belong to?

It belongs to category M85 – Other disorders of bone density and structure.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.