M65.821 — Other synovitis and tenosynovitis, right upper arm
Is M65.821 billable?
Yes — M65.821 is billable for FY2027. M65.821 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. M65.821 may be submitted for encounters from October 1, 2026 through September 30, 2027.
M65.821 at a glance
| Code | M65.821 |
|---|---|
| Description | Other synovitis and tenosynovitis, right upper arm |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does M65.821 group to?
M65.821 sits in MDC 08 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 557Tendonitis, Myositis and Bursitis with MCCmedical
- 558Tendonitis, Myositis and Bursitis without MCCmedical
How is M65.821 listed in the Alphabetic Index?
The Alphabetic Index lists these routes under M65.82, the nearest indexed parent of M65.821. Use them to find the family, then select the specific code.
- Tenosynovitis › specified type NEC › upper arm
Excludes1 — never code together — inherited from M65
The conditions below can never be reported together with M65.821 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 13
The conditions below are not part of M65.821, but a patient may have both at the same time. When documentation supports it, M65.821 and the excluded code may both be reported.
- 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)
How long has M65.821 existed?
M65.821 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.