S22 vs S22.4
S22 and S22.4 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 S22.4
flail chest (S22.5-)
S22
Fracture of rib(s), sternum and thoracic spine
Not billable
- Chapter 19
- Injury, poisoning and certain other consequences of external causes
- Section
- S20-S29
Use when the record says
- fracture of thoracic neural arch
- fracture of thoracic spinous process
- fracture of thoracic transverse process
- fracture of thoracic vertebra
- fracture of thoracic vertebral arch
S22.4
Multiple fractures of ribs
Not billable
- Chapter 19
- Injury, poisoning and certain other consequences of external causes
- Section
- S20-S29
Use when the record says
- Fractures of two or more ribs
Indexed under
- Fracture, traumatic › rib › multiple (abduction) (adduction) (separation)
- Fracture, traumatic › thorax › rib › multiple (abduction) (adduction) (separation)
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