2026 ICD-10-CM Diagnosis Code S33.6XXASprain of sacroiliac joint, initial encounter
S33.6XXA is a billable ICD-10-CM diagnosis code for sprain of sacroiliac joint, 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 551 through 552, 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Sprains and strains, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Closed complete rupture sacroiliac joint
- Complete disruption of pelvic ring
- Complete tear, sacroiliac ligament
- Disorder of left sacroiliac joint
- Disorder of right sacroiliac joint
- Open complete rupture of sacroiliac joint
- Open dislocation of sacroiliac joint
- Sacrum sprain
- Sprain of anterior sacroiliac ligament
- Sprain of left sacroiliac ligament
- Sprain of posterior sacroiliac ligament
- Sprain of right sacroiliac ligament
- Sprain of sacroiliac ligament
- Sprain of sacroiliac region
- Sprain pelvic ligament
- Sprain, symphysis pubis
- Traumatic dislocation of sacroiliac joint
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Dislocation and sprain of joints and ligaments of lumbar spine and pelvis (S33). 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
Spine Injuries and Disorders
Your backbone, or spine, is made up of 26 bone discs called vertebrae. The vertebrae protect your spinal cord and allow you to stand and bend. A number of problems can change the structure of the spine or damage the vertebrae and surrounding tissue. They include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S33.6XXA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S33.6XXAOverview
Is S33.6XXA (Sprain of sacroiliac joint) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report sprain of sacroiliac joint, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S33.6XXA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for sprain of sacroiliac joint, such as an emergency visit or first evaluation.
What MS-DRG does S33.6XXA group to?
When sprain of sacroiliac joint, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 551, 552, 963, 964, 965, with relative weights from 0.9405 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S33.6XXA?
Under the General Equivalence Mappings, sprain of sacroiliac joint, initial encounter converts to ICD-9-CM 846.1 (sprain sacroiliac). 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.
