Is M23.004 a billable ICD-10-CM code?

Yes. M23.004 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does M23.004 sit in the tabular list?

Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Other joint disorders (M20-M25).

What cannot be coded together with M23.004?

M23.004 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above M23.004 (M23) and apply to it just the same.

M23.004

M23.004 — Cystic meniscus, unspecified medial meniscus, left knee

Billable / specific codeICD-10-CMleft

M23.004 is a billable, specific ICD-10-CM code for cystic meniscus, unspecified medial meniscus, left knee. It is valid for submission on a claim.

Excludes1 inherited from the categories above M23.004

These are not written on M23.004, but they bind it: a note on a category applies to every code beneath it. Billing M23.004 with anything listed here is a denial.

Written on M23 — Internal derangement of knee

ankylosis (M24.66)
deformity of knee (M21.-)
osteochondritis dissecans (M93.2)

Excludes2 inherited from the categories above M23.004

Also inherited, and the opposite of Excludes1: these conditions are not part of M23.004, but a patient can have both, so you may code both.

Written on M23 — Internal derangement of knee

current injury - see injury of knee and lower leg (S80-S89)
recurrent dislocation or subluxation of joints (M24.4)
recurrent dislocation or subluxation of patella (M22.0-M22.1)

Risk adjustment

M23.004 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

M23.004 is named in 11 Medicare coverage policies — 4 listing it as supporting medical necessity, and 7 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A58865Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
A58883Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
A58893Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
A59374Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered

Code history

M23.004 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share M23.00. If M23.004 is not quite right, the correct code is usually one of these.

Questions about M23.004

Is M23.004 a billable ICD-10-CM code?: Yes. M23.004 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does M23.004 sit in the tabular list?: Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Other joint disorders (M20-M25).
What cannot be coded together with M23.004?: M23.004 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above M23.004 (M23) and apply to it just the same.