M14.66 – Charcot's joint, knee

ICD-10-CM 2027 diagnosis code · Inflammatory polyarthropathies

Non-billable header

ICD-10-CM code M14.66

Code: M14.66 (claims format: M1466)
Description: Charcot's joint, knee
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: M05-M14 Inflammatory polyarthropathies
Parent codes: M14 › M14.6

Billable codes under M14.66

M14.66 is a header code and cannot be used on claims. Choose the most specific code:

M14.661 – Charcot's joint, right kneeBillable
M14.662 – Charcot's joint, left kneeBillable
M14.669 – Charcot's joint, unspecified kneeBillable

Notes inherited from parent codes

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

M14 – Arthropathies in other diseases classified elsewhere

Excludes1 (not coded here):

arthropathy in:
diabetes mellitus (E08-E13 with .61-)
hematological disorders (M36.2-M36.3)
hypersensitivity reactions (M36.4)
neoplastic disease (M36.1)
neurosyphillis (A52.16)
sarcoidosis (D86.86)
enteropathic arthropathies (M07.-)
juvenile psoriatic arthropathy (L40.54)
lipoid dermatoarthritis (E78.81)

M14.6 – Charcot's joint

Applicable to:

Neuropathic arthropathy

Excludes1 (not coded here):

Charcôt's joint in diabetes mellitus (E08-E13 with .610)
Charcôt's joint in tabes dorsalis (A52.16)

Index terms for M14.66

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

Arthropathy, neuropathic, knee

Related codes in M14.6

M14.60 – Charcot's joint, unspecified siteBillable
M14.61 – Charcot's joint, shoulderHeader
M14.62 – Charcot's joint, elbowHeader
M14.63 – Charcot's joint, wristHeader
M14.64 – Charcot's joint, handHeader
M14.65 – Charcot's joint, hipHeader
M14.67 – Charcot's joint, ankle and footHeader
M14.68 – Charcot's joint, vertebraeBillable
M14.69 – Charcot's joint, multiple sitesBillable

Frequently asked questions

What is ICD-10 code M14.66?

M14.66 is the ICD-10-CM code for charcot's joint, knee, in the block M05-M14 (Inflammatory polyarthropathies).

Is M14.66 a billable code?

No. M14.66 is a header code with more specific child codes; report one of the billable codes listed above.

What category does M14.66 belong to?

It belongs to category M14 – Arthropathies in other diseases classified elsewhere.

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.