S02.109B — Fracture of base of skull, unspecified side, initial encounter for open fracture
Is S02.109B billable?
Yes, but S02.109B will trip a Medicare edit. S02.109B is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, CMS lists S02.109B 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.
S02.109B at a glance
| Code | S02.109B |
|---|---|
| Description | Fracture of base of skull, unspecified side, initial encounter for open fracture |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "B" | initial encounter for open fracture |
What does the 7th character "B" mean in S02.109B?
In S02.109B, the 7th character B means initial encounter for open fracture. The 7th character is required for S02.109B to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
What Medicare edits apply to S02.109B?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name S02.109B 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 S02.109B group to?
S02.109B sits in MDC 01 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.
- 082Traumatic Stupor and Coma >1 Hour with MCCmedical
- 083Traumatic Stupor and Coma >1 Hour with CCmedical
- 084Traumatic Stupor and Coma >1 Hour without CC/MCCmedical
As a secondary diagnosis, S02.109B is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG. It also carries Hospital-Acquired Condition category 05.
How is S02.109B listed in the Alphabetic Index?
The Alphabetic Index lists these routes under S02.10, the nearest indexed parent of S02.109B. Use them to find the family, then select the specific code.
- Fracture, traumatic › skull › base (abduction) (adduction) (separation)
Use additional code — inherited from Chapter 19
Report an additional code alongside S02.109B to fully describe the condition. S02.109B 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 S02.109B, but a patient may have both at the same time. When documentation supports it, S02.109B and the excluded code may both be reported.
Excludes2 — not included here — inherited from S00-S09
The conditions below are not part of S02.109B, but a patient may have both at the same time. When documentation supports it, S02.109B and the excluded code may both be reported.
- burns and corrosions (T20-T32)
- effects of foreign body in ear (T16)
- effects of foreign body in larynx (T17.3)
- effects of foreign body in mouth NOS (T18.0)
- effects of foreign body in nose (T17.0-T17.1)
- effects of foreign body in pharynx (T17.2)
- effects of foreign body on external eye (T15.-)
- frostbite (T33-T34)
- insect bite or sting, venomous (T63.4)
Excludes2 — not included here — inherited from S02.1
The conditions below are not part of S02.109B, but a patient may have both at the same time. When documentation supports it, S02.109B and the excluded code may both be reported.
Code also — inherited from S00-S09
Two codes may be needed to describe the condition fully. Whether S02.109B is sequenced first depends on the reason for the encounter.
- for any associated infection
Code also — inherited from S02
Two codes may be needed to describe the condition fully. Whether S02.109B is sequenced first depends on the reason for the encounter.
- any associated intracranial injury (S06.-)
How long has S02.109B existed?
S02.109B first appears in FY2018 (FY2017 is not available, so it may have appeared then).
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.