M63.861 — Disorders of muscle in diseases classified elsewhere, right lower leg
Is M63.861 billable?
Yes — M63.861 is billable for FY2027. M63.861 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. M63.861 may be submitted for encounters from October 1, 2026 through September 30, 2027.
M63.861 at a glance
| Code | M63.861 |
|---|---|
| Description | Disorders of muscle in diseases classified elsewhere, right lower leg |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to M63.861?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name M63.861 directly.
This code describes a manifestation of an underlying disease. The underlying condition must be sequenced before it, so it can never be the principal or first-listed diagnosis.
Which MS-DRGs does M63.861 group to?
M63.861 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 M63.861 listed in the Alphabetic Index?
The Alphabetic Index lists these routes under M63.86, the nearest indexed parent of M63.861. Use them to find the family, then select the specific code.
- Leprosy › with muscle disorder › lower leg
- Schistosomiasis › with muscle disorder › lower leg
- Trichinellosis, trichiniasis, trichinelliasis, trichinosis › with muscle disorder › lower leg
Excludes1 — never code together — inherited from M60-M63
The conditions below can never be reported together with M63.861 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes1 — never code together — inherited from M63
The conditions below can never be reported together with M63.861 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Code first — inherited from M63
The underlying condition below must be sequenced before M63.861. M63.861 describes a manifestation and cannot be the principal or first-listed diagnosis.
Excludes2 — not included here — inherited from Chapter 13
The conditions below are not part of M63.861, but a patient may have both at the same time. When documentation supports it, M63.861 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)
Excludes2 — not included here — inherited from M60-M63
The conditions below are not part of M63.861, but a patient may have both at the same time. When documentation supports it, M63.861 and the excluded code may both be reported.
- muscular dystrophies and myopathies (G71-G72)
How long has M63.861 existed?
M63.861 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.