M79.ANontraumatic compartment syndrome

M79.A is the ICD-10-CM diagnosis code for nontraumatic compartment syndrome. It belongs to category M79 (other and unspecified soft tissue disorders, not elsewhere classified), block M70-M79 (other soft tissue disorders) and chapter 13 (diseases of the musculoskeletal system and connective tissue). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.

Within M79 (other and unspecified soft tissue disorders, not elsewhere classified), M79.A is specifically for nontraumatic compartment syndrome. Related codes cover rheumatism, unspecified (M79.0), myalgia (M79.1), neuralgia and neuritis, unspecified (M79.2), panniculitis, unspecified (M79.3), hypertrophy of (infrapatellar) fat pad (M79.4), residual foreign body in soft tissue (M79.5), pain in limb, hand, foot, fingers and toes (M79.6), Fibromyalgia (M79.7) and 2 more.

To report this condition, pick the subcode that matches the documentation: M79.A1 (of upper extremity), M79.A2 (of lower extremity), M79.A3 (of abdomen) and M79.A9 (of other sites).

Don't report M79.A together with the conditions in its Excludes1 note: compartment syndrome NOS (T79.A-), fibromyalgia (M79.7), nontraumatic ischemic infarction of muscle (M62.2-) and traumatic compartment syndrome (T79.A-).

Code first: , if applicable, associated postprocedural complication.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.