Is M79 a billable ICD-10-CM code?

No. M79 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does M79 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?

M79 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

M79

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

Non-billable headerICD-10-CM

M79 is a non-billable header ICD-10-CM code for other and unspecified soft tissue disorders, not elsewhere classified. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

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

Other codes that can never be billed with M79

These codes carry an Excludes1 note pointing at M79. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M79 alone.

L95Vasculitis limited to skin, not elsewhere classified
M35.6Relapsing panniculitis [Weber-Christian]
M54.0Panniculitis affecting regions of neck and back
M54.1Radiculopathy
M62Other disorders of muscle
M62.2Nontraumatic ischemic infarction of muscle
M79.0Rheumatism, unspecified
M79.1Myalgia

Risk adjustment

M79 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.

Code to one of these instead M79

11 child codes. Green means billable.

Questions about M79

Is M79 a billable ICD-10-CM code?: No. M79 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does M79 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?: M79 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.