2026 ICD-10-CM Diagnosis Code S91.105SUnspecified open wound of left lesser toe(s) without damage to nail, sequela
S91.105S is a billable ICD-10-CM diagnosis code for unspecified open wound of left lesser toe(s) without damage to nail, sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 604 through 605. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
S91.105S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Open fracture distal phalanx, toe
- Open fracture middle phalanx, toe
- Open fracture of distal phalanx of lesser toe of left foot
- Open fracture of middle phalanx of lesser toe
- Open fracture of middle phalanx of lesser toe of left foot
- Open fracture of phalanx of left foot
- Open fracture of phalanx of lesser toe
- Open fracture of phalanx of lesser toe of left foot
- Open fracture of proximal phalanx of lesser toe of left foot
- Open fracture proximal phalanx, toe
- Open traumatic dislocation of interphalangeal joint of lesser toe of left foot
- Open traumatic dislocation of joint of left foot
- Open traumatic dislocation of joint of left toe
- Open wound of lesser toe of left foot
- Traumatic dislocation of interphalangeal joint of lesser toe
- Traumatic dislocation of lesser toe
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Open wound of ankle, foot and toes (S91). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Toe Injuries and Disorders
Fourteen of the 26 bones in your feet are in your toes. The toes, particularly your big toe, help you move and keep your balance. Playing sports, running, stubbing your toe, and dropping something on your foot can damage your toes. Wearing shoes that are too loose or too tight can also cause toe problems.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S91.105S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S91.105SOverview
Is S91.105S a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified open wound of left lesser toe(s) without damage to nail, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in S91.105S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the unspecified open wound of left lesser toe(s) without damage to nail itself has resolved, not the original event.
What MS-DRG does S91.105S group to?
When unspecified open wound of left lesser toe(s) without damage to nail, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, with relative weights from 0.9160 to 1.4721 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S91.105S exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for unspecified open wound of left lesser toe(s) without damage to nail, sequela on inpatient claims.
What is the ICD-9 equivalent of S91.105S?
Under the General Equivalence Mappings, unspecified open wound of left lesser toe(s) without damage to nail, sequela converts to ICD-9-CM 906.1 (late eff open wnd extrem). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
