M24 vs M35.7
M24 and M35.7 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on M35.7
ligamentous laxity, NOS (M24.2-)
M24
Other specific joint derangements
Not billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M20-M25
M35.7
Hypermobility syndrome
Billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M30-M36
Use when the record says
- Familial ligamentous laxity
Indexed under
- Hypermobility, hypermotility › syndrome
- Syndrome › hypermobility
- Lax, laxity › ligament › familial
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