2026 ICD-10-CM Diagnosis Code S93.419ASprain of calcaneofibular ligament of unspecified ankle, initial encounter
S93.419A is a billable ICD-10-CM diagnosis code for sprain of calcaneofibular ligament of unspecified ankle, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 562 through 563, 963 through 965. Coders also document this condition as rupture of ankle ligament. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Sprains and strains, initial encounter.
This medical diagnosis code is frequently used in Orthopedics medical specialties to designate conditions such selected sprains rotator cuff, cruciate ligament, and ankle.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Rupture of ankle ligament
- Rupture of calcaneofibular ligament
- Sprain of calcaneofibular ligament
- Sprain of lateral ligament of ankle joint
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Dislocation and sprain of joints and ligaments at ankle, foot and toe level (S93). 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
Ankle Injuries and Disorders
Your ankle bone and the ends of your two lower leg bones make up the ankle joint. Your ligaments, which connect bones to one another, stabilize and support it. Your muscles and tendons move it.
Read the full article at MedlinePlus
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Convert S93.419A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S93.419AOverview
Is S93.419A (Sprain of calcaneofibular ligament of unspecified ankle) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report sprain of calcaneofibular ligament of unspecified ankle, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S93.419A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for sprain of calcaneofibular ligament of unspecified ankle, such as an emergency visit or first evaluation.
What MS-DRG does S93.419A group to?
When sprain of calcaneofibular ligament of unspecified ankle, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 562, 563, 963, 964, 965, with relative weights from 0.8955 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S93.419A?
Under the General Equivalence Mappings, sprain of calcaneofibular ligament of unspecified ankle, initial encounter converts to ICD-9-CM 845.02 (sprain calcaneofibular). 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.
