2026 ICD-10-CM Diagnosis Code S72.21XBDisplaced subtrochanteric fracture of right femur, initial encounter for open fracture type I or II
S72.21XB is a billable ICD-10-CM diagnosis code for displaced subtrochanteric fracture of right femur, initial encounter for open fracture type I or II. The 7th character B reports the initial encounter for an open fracture. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 521 through 522, 535 through 536, 963 through 965. Coders also document this condition as closed fracture proximal femur, subtrochanteric. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of the neck of the femur (hip), initial encounter.
Code Identity
Code Classification
Quality Payment Program MeasuresBilling
Medicare quality measures that can apply when S72.21XB is part of the patient record.
Communication with the Physician or Other Clinician Managing On-Going Care Post-Fracture for Men and Women Aged 50 Years and Older
High Priority: YES
Measure Type: Process
Submission Methods: Claims, Registry
Description: Percentage of patients aged 50 years and older treated for a fracture with documentation of communication, between the physician treating the fracture and the physician or other clinician managing the patient's on-going care, that a fracture occurred and that the patient was or should be considered for osteoporosis treatment or testing. This measure is submitted by the physician who treats the fracture and who therefore is held accountable for the communication.
Osteoporosis Management in Women Who Had a Fracture
High Priority: NO
Measure Type: Process
Submission Methods: Claims, Registry
Description: The percentage of women 50-85 years of age who suffered a fracture and who had either a bone mineral density (BMD) test or prescription for a drug to treat osteoporosis in the six months after the fracture.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Closed fracture proximal femur, subtrochanteric
- Closed subtrochanteric fracture of right femur
- Open subtrochanteric fracture of right femur
- Subtrochanteric fracture of femur
- Subtrochanteric fracture of right femur
Coding GuidelinesGuidance
The principles of multiple coding of injuries should be followed in coding fractures. Fractures of specified sites are coded individually by site, to the level of detail furnished by medical record content.
A fracture not indicated as open or closed should be coded to closed. A fracture not indicated whether displaced or not displaced should be coded to displaced.
Initial vs. Subsequent Encounter for Fractures
Traumatic fractures are coded using the appropriate 7th character for initial encounter (A, B, C) while the patient is receiving active treatment for the fracture. The appropriate 7th character for initial encounter should also be assigned for a patient who delayed seeking treatment for the fracture or nonunion.
Fractures are coded using the appropriate 7th character for subsequent care for encounters after the patient has completed active treatment of the fracture and is receiving routine care for the fracture during the healing or recovery phase.
Care for complications of surgical treatment for fracture repairs during the healing or recovery phase should be coded with the appropriate complication codes.
Care of complications of fractures, such as malunion and nonunion, should be reported with the appropriate 7th character for subsequent care with nonunion (K, M, N) or subsequent care with malunion (P, Q, R).
The open fracture designations in the assignment of the 7th character for fractures of the forearm, femur and lower leg, including ankle are based on the Gustilo open fracture classification. When the Gustilo classification type is not specified for an open fracture, the 7th character for open fracture type I or II should be assigned (B, E, H, M, Q).
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
Fractures
A fracture is a break in a bone. Fractures are usually caused by injuries. Since they can sometimes be serious, it's important to get medical care right away if you think you have a fracture.
The full article covers:
- What is a fracture?
- What are the different types of fractures?
- What causes fractures?
- What are the symptoms of a fracture?
- How are fractures diagnosed?
- What are the treatments for fractures?
- Can fractures be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S72.21XB to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S72.21XBOverview
Is S72.21XB (Displaced subtrochanteric fracture of right femur) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report displaced subtrochanteric fracture of right femur, initial encounter for open fracture type I or II on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character B in S72.21XB mean?
The final character B reports the initial encounter for an open fracture, in this case involving the displaced subtrochanteric fracture of right femur.
What MS-DRG does S72.21XB group to?
When displaced subtrochanteric fracture of right femur, initial encounter for open fracture type I or II is the principal diagnosis on an inpatient stay, it groups to MS-DRG 521, 522, 535, 536, 963, 964, 965, with relative weights from 0.8076 to 2.8702 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S72.21XB?
Under the General Equivalence Mappings, displaced subtrochanteric fracture of right femur, initial encounter for open fracture type I or II converts to ICD-9-CM 820.32 (subtrochanteric fx-open). 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.
