ICD-10-CM Tabular Index · Chapter 13 · FY 2026 M85

Other disorders of bone density and structure (M85) ICD-10-CM

The M85 code range covers other disorders of bone density and structure with 226 ICD-10-CM diagnosis codes. 169 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.

✓ Built from the official CMS FY 2026 datasetEffective Oct 1, 2025 – Sep 30, 2026
226
Diagnosis Codes
169
Billable Codes
M85
Code Range
M80–M85
Parent Section

Type 1 Excludes

A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

ICD-10-CM

Codes in the M85 Range 226 codes · 169 billable

226 of 226 shown
  • M85 Other disorders of bone density and structureNon-billable
  • M85.0 Fibrous dysplasia (monostotic)Non-billable
  • M85.00 Fibrous dysplasia (monostotic), unspecified site
  • M85.01 Fibrous dysplasia (monostotic), shoulderNon-billable
  • M85.011 Fibrous dysplasia (monostotic), right shoulder
  • M85.012 Fibrous dysplasia (monostotic), left shoulder
  • M85.019 Fibrous dysplasia (monostotic), unspecified shoulder
  • M85.02 Fibrous dysplasia (monostotic), upper armNon-billable
  • M85.021 Fibrous dysplasia (monostotic), right upper arm
  • M85.022 Fibrous dysplasia (monostotic), left upper arm
  • M85.029 Fibrous dysplasia (monostotic), unspecified upper arm
  • M85.03 Fibrous dysplasia (monostotic), forearmNon-billable
  • M85.031 Fibrous dysplasia (monostotic), right forearm
  • M85.032 Fibrous dysplasia (monostotic), left forearm
  • M85.039 Fibrous dysplasia (monostotic), unspecified forearm
  • M85.04 Fibrous dysplasia (monostotic), handNon-billable
  • M85.041 Fibrous dysplasia (monostotic), right hand
  • M85.042 Fibrous dysplasia (monostotic), left hand
  • M85.049 Fibrous dysplasia (monostotic), unspecified hand
  • M85.05 Fibrous dysplasia (monostotic), thighNon-billable
  • M85.051 Fibrous dysplasia (monostotic), right thigh
  • M85.052 Fibrous dysplasia (monostotic), left thigh
  • M85.059 Fibrous dysplasia (monostotic), unspecified thigh
  • M85.06 Fibrous dysplasia (monostotic), lower legNon-billable
  • M85.061 Fibrous dysplasia (monostotic), right lower leg
  • M85.062 Fibrous dysplasia (monostotic), left lower leg
  • M85.069 Fibrous dysplasia (monostotic), unspecified lower leg
  • M85.07 Fibrous dysplasia (monostotic), ankle and footNon-billable
  • M85.071 Fibrous dysplasia (monostotic), right ankle and foot
  • M85.072 Fibrous dysplasia (monostotic), left ankle and foot
  • M85.079 Fibrous dysplasia (monostotic), unspecified ankle and foot
  • M85.08 Fibrous dysplasia (monostotic), other site
  • M85.09 Fibrous dysplasia (monostotic), multiple sites
  • M85.1 Skeletal fluorosisNon-billable
  • M85.10 Skeletal fluorosis, unspecified site
  • M85.11 Skeletal fluorosis, shoulderNon-billable
  • M85.111 Skeletal fluorosis, right shoulder
  • M85.112 Skeletal fluorosis, left shoulder
  • M85.119 Skeletal fluorosis, unspecified shoulder
  • M85.12 Skeletal fluorosis, upper armNon-billable
  • M85.121 Skeletal fluorosis, right upper arm
  • M85.122 Skeletal fluorosis, left upper arm
  • M85.129 Skeletal fluorosis, unspecified upper arm
  • M85.13 Skeletal fluorosis, forearmNon-billable
  • M85.131 Skeletal fluorosis, right forearm
  • M85.132 Skeletal fluorosis, left forearm
  • M85.139 Skeletal fluorosis, unspecified forearm
  • M85.14 Skeletal fluorosis, handNon-billable
  • M85.141 Skeletal fluorosis, right hand
  • M85.142 Skeletal fluorosis, left hand
  • M85.149 Skeletal fluorosis, unspecified hand
  • M85.15 Skeletal fluorosis, thighNon-billable
  • M85.151 Skeletal fluorosis, right thigh
  • M85.152 Skeletal fluorosis, left thigh
  • M85.159 Skeletal fluorosis, unspecified thigh
  • M85.16 Skeletal fluorosis, lower legNon-billable
  • M85.161 Skeletal fluorosis, right lower leg
  • M85.162 Skeletal fluorosis, left lower leg
  • M85.169 Skeletal fluorosis, unspecified lower leg
  • M85.17 Skeletal fluorosis, ankle and footNon-billable
  • M85.171 Skeletal fluorosis, right ankle and foot
  • M85.172 Skeletal fluorosis, left ankle and foot
  • M85.179 Skeletal fluorosis, unspecified ankle and foot
  • M85.18 Skeletal fluorosis, other site
  • M85.19 Skeletal fluorosis, multiple sites
  • M85.2 Hyperostosis of skull
  • M85.3 Osteitis condensansNon-billable
  • M85.30 Osteitis condensans, unspecified site
  • M85.31 Osteitis condensans, shoulderNon-billable
  • M85.311 Osteitis condensans, right shoulder
  • M85.312 Osteitis condensans, left shoulder
  • M85.319 Osteitis condensans, unspecified shoulder
  • M85.32 Osteitis condensans, upper armNon-billable
  • M85.321 Osteitis condensans, right upper arm
  • M85.322 Osteitis condensans, left upper arm
  • M85.329 Osteitis condensans, unspecified upper arm
  • M85.33 Osteitis condensans, forearmNon-billable
  • M85.331 Osteitis condensans, right forearm
  • M85.332 Osteitis condensans, left forearm
  • M85.339 Osteitis condensans, unspecified forearm
  • M85.34 Osteitis condensans, handNon-billable
  • M85.341 Osteitis condensans, right hand
  • M85.342 Osteitis condensans, left hand
  • M85.349 Osteitis condensans, unspecified hand
  • M85.35 Osteitis condensans, thighNon-billable
  • M85.351 Osteitis condensans, right thigh
  • M85.352 Osteitis condensans, left thigh
  • M85.359 Osteitis condensans, unspecified thigh
  • M85.36 Osteitis condensans, lower legNon-billable
  • M85.361 Osteitis condensans, right lower leg
  • M85.362 Osteitis condensans, left lower leg
  • M85.369 Osteitis condensans, unspecified lower leg
  • M85.37 Osteitis condensans, ankle and footNon-billable
  • M85.371 Osteitis condensans, right ankle and foot
  • M85.372 Osteitis condensans, left ankle and foot
  • M85.379 Osteitis condensans, unspecified ankle and foot
  • M85.38 Osteitis condensans, other site
  • M85.39 Osteitis condensans, multiple sites
  • M85.4 Solitary bone cystNon-billable
  • M85.40 Solitary bone cyst, unspecified site
  • M85.41 Solitary bone cyst, shoulderNon-billable
  • M85.411 Solitary bone cyst, right shoulder
  • M85.412 Solitary bone cyst, left shoulder
  • M85.419 Solitary bone cyst, unspecified shoulder
  • M85.42 Solitary bone cyst, humerusNon-billable
  • M85.421 Solitary bone cyst, right humerus
  • M85.422 Solitary bone cyst, left humerus
  • M85.429 Solitary bone cyst, unspecified humerus
  • M85.43 Solitary bone cyst, ulna and radiusNon-billable
  • M85.431 Solitary bone cyst, right ulna and radius
  • M85.432 Solitary bone cyst, left ulna and radius
  • M85.439 Solitary bone cyst, unspecified ulna and radius
  • M85.44 Solitary bone cyst, handNon-billable
  • M85.441 Solitary bone cyst, right hand
  • M85.442 Solitary bone cyst, left hand
  • M85.449 Solitary bone cyst, unspecified hand
  • M85.45 Solitary bone cyst, pelvisNon-billable
  • M85.451 Solitary bone cyst, right pelvis
  • M85.452 Solitary bone cyst, left pelvis
  • M85.459 Solitary bone cyst, unspecified pelvis
  • M85.46 Solitary bone cyst, tibia and fibulaNon-billable
  • M85.461 Solitary bone cyst, right tibia and fibula
  • M85.462 Solitary bone cyst, left tibia and fibula
  • M85.469 Solitary bone cyst, unspecified tibia and fibula
  • M85.47 Solitary bone cyst, ankle and footNon-billable
  • M85.471 Solitary bone cyst, right ankle and foot
  • M85.472 Solitary bone cyst, left ankle and foot
  • M85.479 Solitary bone cyst, unspecified ankle and foot
  • M85.48 Solitary bone cyst, other site
  • M85.5 Aneurysmal bone cystNon-billable
  • M85.50 Aneurysmal bone cyst, unspecified site
  • M85.51 Aneurysmal bone cyst, shoulderNon-billable
  • M85.511 Aneurysmal bone cyst, right shoulder
  • M85.512 Aneurysmal bone cyst, left shoulder
  • M85.519 Aneurysmal bone cyst, unspecified shoulder
  • M85.52 Aneurysmal bone cyst, upper armNon-billable
  • M85.521 Aneurysmal bone cyst, right upper arm
  • M85.522 Aneurysmal bone cyst, left upper arm
  • M85.529 Aneurysmal bone cyst, unspecified upper arm
  • M85.53 Aneurysmal bone cyst, forearmNon-billable
  • M85.531 Aneurysmal bone cyst, right forearm
  • M85.532 Aneurysmal bone cyst, left forearm
  • M85.539 Aneurysmal bone cyst, unspecified forearm
  • M85.54 Aneurysmal bone cyst, handNon-billable
  • M85.541 Aneurysmal bone cyst, right hand
  • M85.542 Aneurysmal bone cyst, left hand
  • M85.549 Aneurysmal bone cyst, unspecified hand
  • M85.55 Aneurysmal bone cyst, thighNon-billable
  • M85.551 Aneurysmal bone cyst, right thigh
  • M85.552 Aneurysmal bone cyst, left thigh
  • M85.559 Aneurysmal bone cyst, unspecified thigh
  • M85.56 Aneurysmal bone cyst, lower legNon-billable
  • M85.561 Aneurysmal bone cyst, right lower leg
  • M85.562 Aneurysmal bone cyst, left lower leg
  • M85.569 Aneurysmal bone cyst, unspecified lower leg
  • M85.57 Aneurysmal bone cyst, ankle and footNon-billable
  • M85.571 Aneurysmal bone cyst, right ankle and foot
  • M85.572 Aneurysmal bone cyst, left ankle and foot
  • M85.579 Aneurysmal bone cyst, unspecified ankle and foot
  • M85.58 Aneurysmal bone cyst, other site
  • M85.59 Aneurysmal bone cyst, multiple sites
  • M85.6 Other cyst of boneNon-billable
  • M85.60 Other cyst of bone, unspecified site
  • M85.61 Other cyst of bone, shoulderNon-billable
  • M85.611 Other cyst of bone, right shoulder
  • M85.612 Other cyst of bone, left shoulder
  • M85.619 Other cyst of bone, unspecified shoulder
  • M85.62 Other cyst of bone, upper armNon-billable
  • M85.621 Other cyst of bone, right upper arm
  • M85.622 Other cyst of bone, left upper arm
  • M85.629 Other cyst of bone, unspecified upper arm
  • M85.63 Other cyst of bone, forearmNon-billable
  • M85.631 Other cyst of bone, right forearm
  • M85.632 Other cyst of bone, left forearm
  • M85.639 Other cyst of bone, unspecified forearm
  • M85.64 Other cyst of bone, handNon-billable
  • M85.641 Other cyst of bone, right hand
  • M85.642 Other cyst of bone, left hand
  • M85.649 Other cyst of bone, unspecified hand
  • M85.65 Other cyst of bone, thighNon-billable
  • M85.651 Other cyst of bone, right thigh
  • M85.652 Other cyst of bone, left thigh
  • M85.659 Other cyst of bone, unspecified thigh
  • M85.66 Other cyst of bone, lower legNon-billable
  • M85.661 Other cyst of bone, right lower leg
  • M85.662 Other cyst of bone, left lower leg
  • M85.669 Other cyst of bone, unspecified lower leg
  • M85.67 Other cyst of bone, ankle and footNon-billable
  • M85.671 Other cyst of bone, right ankle and foot
  • M85.672 Other cyst of bone, left ankle and foot
  • M85.679 Other cyst of bone, unspecified ankle and foot
  • M85.68 Other cyst of bone, other site
  • M85.69 Other cyst of bone, multiple sites
  • M85.8 Other specified disorders of bone density and structureNon-billable
  • M85.80 Other specified disorders of bone density and structure, unspecified site
  • M85.81 Other specified disorders of bone density and structure, shoulderNon-billable
  • M85.811 Other specified disorders of bone density and structure, right shoulder
  • M85.812 Other specified disorders of bone density and structure, left shoulder
  • M85.819 Other specified disorders of bone density and structure, unspecified shoulder
  • M85.82 Other specified disorders of bone density and structure, upper armNon-billable
  • M85.821 Other specified disorders of bone density and structure, right upper arm
  • M85.822 Other specified disorders of bone density and structure, left upper arm
  • M85.829 Other specified disorders of bone density and structure, unspecified upper arm
  • M85.83 Other specified disorders of bone density and structure, forearmNon-billable
  • M85.831 Other specified disorders of bone density and structure, right forearm
  • M85.832 Other specified disorders of bone density and structure, left forearm
  • M85.839 Other specified disorders of bone density and structure, unspecified forearm
  • M85.84 Other specified disorders of bone density and structure, handNon-billable
  • M85.841 Other specified disorders of bone density and structure, right hand
  • M85.842 Other specified disorders of bone density and structure, left hand
  • M85.849 Other specified disorders of bone density and structure, unspecified hand
  • M85.85 Other specified disorders of bone density and structure, thighNon-billable
  • M85.851 Other specified disorders of bone density and structure, right thigh
  • M85.852 Other specified disorders of bone density and structure, left thigh
  • M85.859 Other specified disorders of bone density and structure, unspecified thigh
  • M85.86 Other specified disorders of bone density and structure, lower legNon-billable
  • M85.861 Other specified disorders of bone density and structure, right lower leg
  • M85.862 Other specified disorders of bone density and structure, left lower leg
  • M85.869 Other specified disorders of bone density and structure, unspecified lower leg
  • M85.87 Other specified disorders of bone density and structure, ankle and footNon-billable
  • M85.871 Other specified disorders of bone density and structure, right ankle and foot
  • M85.872 Other specified disorders of bone density and structure, left ankle and foot
  • M85.879 Other specified disorders of bone density and structure, unspecified ankle and foot
  • M85.88 Other specified disorders of bone density and structure, other site
  • M85.89 Other specified disorders of bone density and structure, multiple sites
  • M85.9 Disorder of bone density and structure, unspecified

Clinical Terms in This Code Range

Definitions from the National Library of Medicine for conditions coded in the M85 range.

Fibrous Dysplasia of Bone

A disease of bone marked by thinning of the cortex by fibrous tissue containing bony spicules, producing pain, disability, and gradually increasing deformity. Only one bone may be involved (FIBROUS DYSPLASIA, MONOSTOTIC) or several (FIBROUS DYSPLASIA, POLYOSTOTIC).

Hyaline Fibromatosis Syndrome

Autosomal recessive disorder characterized by HYALINE deposition in the skin, bone, gastrointestinal tract, muscles and glands; multiple subcutaneous skin nodules; GINGIVAL HYPERTROPHY; and joint CONTRACTURES. Mutations in the capillary morphogenesis protein-2 are associated with the disorder.

Melorheostosis

A form of osteosclerosis extending in a linear track mainly through one of the long bones of the upper and lower limbs.

Osteopoikilosis

An asymptomatic, autosomal dominant trait in which pea-sized sclerotic spots, prominent in the metaphyseal area, are accompanied by unique cutaneous lesions. These are yellowish papules or plaques with increased elastin content. (From Cecil Textbook of Medicine, 19th ed, pp1434-35)

About the M85 Code Range

ICD-10 code M85 covers a group of unique conditions known as other disorders of bone density and structure. These codes are essential for identifying specific bone abnormalities that do not fit into common categories like osteoporosis or osteomalacia.

The ICD-10 codes within M85 include detailed classifications for various bone disorders such as fibrous dysplasia (M85.0), a condition also known by synonyms like Fibrous dysplasia of bone and Monostotic fibrous dysplasia. It specifies affected bone sites like shoulders, arms, and legs. Additionally, codes cover skeletal fluorosis (M85.1), linked to fluoride buildup in bones, and osteitis condensans (M85.3), a localized bone hardening. The section also includes different types of bone cysts—solitary bone cysts (M85.4), aneurysmal bone cysts (M85.5), and other cysts of bone (M85.6). For less common conditions, M85.8 codes specify other disorders with varying bone density or structural changes, including melorheostosis and osteopenia. Finally, M85.9 captures unspecified disorders in this category.

These codes help medical professionals pinpoint and document complex bone diseases accurately, aiding in tailored patient treatment and research. Using synonyms linked to codes like Hyperostosis of skull with M85.2 or Bone cysts with M85.6 guides accurate coding for diverse clinical presentations under M85.

Questions About This Page

How many billable codes are in the M85 range?

Of the 226 codes in this range, 169 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.

What does the M85 range classify?

The range classifies other disorders of bone density and structure. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.

Related References

All ICD-10-CM ChaptersAll of Chapter 13ICD-10-CM Code LookupMS-DRG ReferenceMedicare Code EditsPOA Exempt Codes

Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.