Excludes1 pair

M51- vs M54.4-

M51 and M54.4 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on M54.4
lumbago with sciatica due to intervertebral disc disorder (M51.1-)
M51

Thoracic, thoracolumbar, and lumbosacral intervertebral disc disorders

Not billable
Chapter 13
Diseases of the musculoskeletal system and connective tissue
Section
M50-M54
M54.4

Lumbago with sciatica

Not billable
Chapter 13
Diseases of the musculoskeletal system and connective tissue
Section
M50-M54
Indexed under
  • Lumbago, lumbalgia › with sciatica
  • Rheumatism › sciatic
  • Sciatica › with lumbago
  • Scoliosis › sciatic
  • Pain › spine › low back › with sciatica

Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027