S42.409P — Unspecified fracture of lower end of unspecified humerus, subsequent encounter for fracture with malunion
Is S42.409P billable?
Yes, but S42.409P will trip a Medicare edit. S42.409P is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, CMS lists S42.409P under Medicare Code Editor edit 20, “Unspecified code” — meaning a code specifying laterality (right, left or bilateral) exists in the same family. On an inpatient claim this triggers the edit, because CMS holds that there are very limited circumstances in which laterality cannot be documented.
More specific alternatives
- S42.411PDisplaced simple supracondylar fracture without intercondylar fracture of right humerus, subsequent encounter for fracture with malunion
- S42.421PDisplaced comminuted supracondylar fracture without intercondylar fracture of right humerus, subsequent encounter for fracture with malunion
- S42.431PDisplaced fracture (avulsion) of lateral epicondyle of right humerus, subsequent encounter for fracture with malunion
- S42.441PDisplaced fracture (avulsion) of medial epicondyle of right humerus, subsequent encounter for fracture with malunion
- S42.451PDisplaced fracture of lateral condyle of right humerus, subsequent encounter for fracture with malunion
- S42.461PDisplaced fracture of medial condyle of right humerus, subsequent encounter for fracture with malunion
- S42.471PDisplaced transcondylar fracture of right humerus, subsequent encounter for fracture with malunion
- S42.481PTorus fracture of lower end of right humerus, subsequent encounter for fracture with malunion
- S42.491POther displaced fracture of lower end of right humerus, subsequent encounter for fracture with malunion
S42.409P at a glance
| Code | S42.409P |
|---|---|
| Description | Unspecified fracture of lower end of unspecified humerus, subsequent encounter for fracture with malunion |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "P" | subsequent encounter for fracture with malunion |
What does the 7th character "P" mean in S42.409P?
In S42.409P, the 7th character P means subsequent encounter for fracture with malunion. The 7th character is required for S42.409P to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
- Ainitial encounter for closed fractureS42.409A
- Binitial encounter for open fractureS42.409B
- Dsubsequent encounter for fracture with routine healingS42.409D
- Gsubsequent encounter for fracture with delayed healingS42.409G
- Ksubsequent encounter for fracture with nonunionS42.409K
- Psubsequent encounter for fracture with malunionS42.409P
- SsequelaS42.409S
What Medicare edits apply to S42.409P?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name S42.409P directly.
A code specifying laterality (right, left or bilateral) exists in the same family. CMS holds that there are very limited circumstances in which laterality cannot be documented.
Which MS-DRGs does S42.409P group to?
S42.409P sits in MDC 08 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 564Other Musculoskeletal System and Connective Tissue Diagnoses with MCCmedical
- 565Other Musculoskeletal System and Connective Tissue Diagnoses with CCmedical
- 566Other Musculoskeletal System and Connective Tissue Diagnoses without CC/MCCmedical
As a secondary diagnosis, S42.409P is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is S42.409P listed in the Alphabetic Index?
The Alphabetic Index lists these routes under S42.40, the nearest indexed parent of S42.409P. Use them to find the family, then select the specific code.
- Fracture, traumatic › elbow (abduction) (adduction) (separation)
- Fracture, traumatic › humerus › lower end (abduction) (adduction) (separation)
Excludes1 — never code together — inherited from S42
The conditions below can never be reported together with S42.409P on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- traumatic amputation of shoulder and upper arm (S48.-)
Use additional code — inherited from Chapter 19
Report an additional code alongside S42.409P to fully describe the condition. S42.409P is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of S42.409P, but a patient may have both at the same time. When documentation supports it, S42.409P and the excluded code may both be reported.
Excludes2 — not included here — inherited from S40-S49
The conditions below are not part of S42.409P, but a patient may have both at the same time. When documentation supports it, S42.409P and the excluded code may both be reported.
Excludes2 — not included here — inherited from S42
The conditions below are not part of S42.409P, but a patient may have both at the same time. When documentation supports it, S42.409P and the excluded code may both be reported.
- periprosthetic fracture around internal prosthetic shoulder joint (M97.3)
Excludes2 — not included here — inherited from S42.4
The conditions below are not part of S42.409P, but a patient may have both at the same time. When documentation supports it, S42.409P and the excluded code may both be reported.
How long has S42.409P existed?
S42.409P has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.