2026 ICD-10-CM Diagnosis Code N83.521Torsion of right fallopian tube

ICD-10-CM Codes›N00–N99›N80-N98›N83

ICD-10-CM N83.521
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N83.521 is a billable ICD-10-CM diagnosis code for torsion of right fallopian tube. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 742 through 743, 760 through 761. Coders also document this condition as torsion of fallopian tube. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified female genital disorders.

Code Identity

ICD-10-CM Code
N83.521
Billable Status
Yes — Valid for Submission
Code Describes
Torsion of right fallopian tube
Short Description
Torsion of right fallopian tube
Same as the full description in the CMS dataset.
Parent Code
N83.52
Torsion of fallopian tube

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN80-N98Noninflammatory disorders of female genital tract
CategoryN83Noninflammatory disorders of ovary, fallopian tube and broad ligament
This CodeN83.521Torsion of right fallopian tube

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Torsion of fallopian tube
  • Torsion of right fallopian tube

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN025
Other specified female genital disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert N83.521 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
620.5 Torsion of ovary or tube
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement N83.521 replaces the following previously assigned code(s):

  • N83.52 - Torsion of fallopian tube
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N83.521Overview

Is N83.521 (Torsion of fallopian tube) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report torsion of right fallopian tube on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N83.521 group to?

When torsion of right fallopian tube is the principal diagnosis on an inpatient stay, it groups to MS-DRG 742, 743, 760, 761, with relative weights from 0.5696 to 1.8348 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N83.521?

Under the General Equivalence Mappings, torsion of right fallopian tube converts to ICD-9-CM 620.5 (torsion of ovary or tube). 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.