ICD-10-CM 2027
ICD-10 code for skeletal fluorosis
From the official ICD-10-CM alphabetic index entry “Fluorosis › skeletal”. Page updated September 29, 2026.
About coding skeletal fluorosis
The ICD-10-CM code for skeletal fluorosis is M85.10 (Skeletal fluorosis, unspecified site). The official index lists 15 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on M85.10.
Within M85.1, choose M85.10 (unspecified site) only when documentation doesn't support a more specific option: shoulder (M85.11), upper arm (M85.12), forearm (M85.13), hand (M85.14), thigh (M85.15), lower leg (M85.16), ankle and foot (M85.17), other site (M85.18) and 1 more.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 564 (Other Musculoskeletal System and Connective Tissue Diagnoses with MCC, relative weight 1.4908), DRG 565 (Other Musculoskeletal System and Connective Tissue Diagnoses with CC, relative weight 0.9783) and DRG 566 (Other Musculoskeletal System and Connective Tissue Diagnoses without CC/MCC, relative weight 0.7378), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific skeletal fluorosis codes (official index)
- ankle M85.17 — Skeletal fluorosis, ankle and foot
- foot M85.17 — Skeletal fluorosis, ankle and foot
- forearm M85.13 — Skeletal fluorosis, forearm
- hand M85.14 — Skeletal fluorosis, hand
- lower leg M85.16 — Skeletal fluorosis, lower leg
- multiple site M85.19 — Skeletal fluorosis, multiple sites
- neck M85.18 — Skeletal fluorosis, other site
- rib M85.18 — Skeletal fluorosis, other site
- shoulder M85.11 — Skeletal fluorosis, shoulder
- skull M85.18 — Skeletal fluorosis, other site
- specified site NEC M85.18 — Skeletal fluorosis, other site
- thigh M85.15 — Skeletal fluorosis, thigh
- toe M85.17 — Skeletal fluorosis, ankle and foot
- upper arm M85.12 — Skeletal fluorosis, upper arm
- vertebra M85.18 — Skeletal fluorosis, other site
Common questions about skeletal fluorosis ICD-10 codes
What is the ICD-10 code for skeletal fluorosis?
- M85.10 — Skeletal fluorosis, unspecified site. More specific codes apply when the documentation supports them: M85.17, M85.17, M85.13, M85.14 and others below.
What is the ICD-10 code for ankle skeletal fluorosis?
- M85.17 — Skeletal fluorosis, ankle and foot (header code; choose a more specific subcode).
What is the ICD-10 code for foot skeletal fluorosis?
- M85.17 — Skeletal fluorosis, ankle and foot (header code; choose a more specific subcode).
What is the ICD-10 code for forearm skeletal fluorosis?
- M85.13 — Skeletal fluorosis, forearm (header code; choose a more specific subcode).
What is the ICD-10 code for hand skeletal fluorosis?
- M85.14 — Skeletal fluorosis, hand (header code; choose a more specific subcode).
What is the ICD-10 code for lower leg skeletal fluorosis?
- M85.16 — Skeletal fluorosis, lower leg (header code; choose a more specific subcode).
What is the ICD-10 code for multiple site skeletal fluorosis?
- M85.19 — Skeletal fluorosis, multiple sites.
Is M85.10 billable?
- Yes. M85.10 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M85.10 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M85.10 as a principal diagnosis.
Is M85.10 a CC or MCC?
- No. M85.10 is neither a CC nor an MCC under MS-DRG v44.0.