Is M79.661 a billable ICD-10-CM code?

Yes. M79.661 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does M79.661 sit in the tabular list?

Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Other soft tissue disorders (M70-M79).

What cannot be coded together with M79.661?

M79.661 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 M79.661 (M79) and apply to it just the same.

M79.661

M79.661 — Pain in right lower leg

Billable / specific codeICD-10-CMright

M79.661 is a billable, specific ICD-10-CM code for pain in right lower leg. It is valid for submission on a claim.

Excludes1 inherited from the categories above M79.661

These are not written on M79.661, but they bind it: a note on a category applies to every code beneath it. Billing M79.661 with anything listed here is a denial.

Written on M79 — Other and unspecified soft tissue disorders, not elsewhere classified

psychogenic rheumatism (F45.8)
soft tissue pain, psychogenic (F45.41)

Excludes2 inherited from the categories above M79.661

Also inherited, and the opposite of Excludes1: these conditions are not part of M79.661, but a patient can have both, so you may code both.

Written on M79.6 — Pain in limb, hand, foot, fingers and toes

pain in joint (M25.5-)

Risk adjustment

M79.661 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

M79.661 is named in 39 Medicare coverage policies — 26 listing it as supporting medical necessity, and 13 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56731Billing and Coding: Nerve Blocks and Electrostimulation for Peripheral Neuropathynot covered
A57701Billing and Coding: Trigger Point Injections (TPI)not covered
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

Code history

M79.661 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 M79.66. If M79.661 is not quite right, the correct code is usually one of these.

Questions about M79.661

Is M79.661 a billable ICD-10-CM code?: Yes. M79.661 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does M79.661 sit in the tabular list?: Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Other soft tissue disorders (M70-M79).
What cannot be coded together with M79.661?: M79.661 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 M79.661 (M79) and apply to it just the same.