2027 ICD-10-CM Diagnosis Code M66.131Rupture of synovium, right wrist
ICD-10-CM Codes›M00–M99›M65-M67›M66
- Billable — Valid for Submission
- Not Chronic
M66.131 is a billable ICD-10-CM diagnosis code for rupture of synovium, right wrist. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 557 through 558. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Tendon and synovial disorders.
Code Identity
Code Classification
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to M66.131: its own notes plus those printed at M66.1, M66, and Chapter 13. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- rotator cuff syndrome (M75.1-)
- rupture where an abnormal force is applied to normal tissue - see injury of tendon by body region
- arthropathic psoriasis (L40.5-)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- compartment syndrome (traumatic) (T79.A-)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
General instructions on how these codes are used.
- Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name M66.131, its category, or a range that includes it.
Excludes1 1
These codes carry an Excludes1 note naming M66.131: they are not reported together with it, unless the two conditions are unrelated.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Wrist Injuries and Disorders
Your wrist connects your hand to your forearm. It is not one big joint; it has several small joints. This makes it flexible and allows you to move your hand in different ways. The wrist has two big forearm bones and eight small bones known as carpals. It also has tendons and ligaments, which are connective tissues.
The full article covers:
- What are the types of wrist injuries and disorders?
- Who is at risk for wrist injuries and disorders?
- What are the symptoms of wrist injuries and disorders?
- How are wrist injuries and disorders diagnosed?
- What are the treatments for wrist injuries and disorders?
- Can wrist injuries and disorders be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert M66.131 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M66.131Overview
What is the ICD-10 code for rupture of synovium, right wrist?
The ICD-10-CM code for rupture of synovium, right wrist is M66.131 (sometimes written as M66131). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is M66.131 (Rupture of synovium, wrist) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report rupture of synovium, right wrist on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does M66.131 group to?
When rupture of synovium, right wrist is the principal diagnosis on an inpatient stay, it groups to MS-DRG 557, 558, with relative weights from 0.8873 to 1.4883 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of M66.131?
Under the General Equivalence Mappings, rupture of synovium, right wrist converts to ICD-9-CM 727.59 (rupture of synovium NEC). The mapping is approximate, so confirm the match fits the documentation.
