M85.661 – Other cyst of bone, right lower leg

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

Billable code

ICD-10-CM code M85.661
Code
M85.661 (claims format: M85661)
Description
Other cyst of bone, right lower leg
Billable
Yes – valid for HIPAA-covered transactions
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 › M85.6 › M85.66

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)

M85.6 – Other cyst of bone

Excludes1 (not coded here):
  • cyst of jaw NEC (M27.4)
  • osteitis fibrosa cystica generalisata [von Recklinghausen's disease of bone] (E21.0)

Related codes in M85.66

Frequently asked questions

What is ICD-10 code M85.661?

M85.661 is the ICD-10-CM code for other cyst of bone, right lower leg, in the block M80-M85 (Disorders of bone density and structure).

Is M85.661 a billable code?

Yes. M85.661 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does M85.661 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.