M12.40
Intermittent hydrarthrosis, unspecified site
Billable FY2026 2025-10-01 → 2026-09-30
This is the unspecified option. 9 more
specific codes sit alongside it. Worth
checking whether the documentation supports one of them.
Exclusions 12 never code together
M00-M99chapter
Excludes2
- arthropathic psoriasis (L40.5-)L40.5-
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- compartment syndrome (traumatic) (T79.A-)T79.A-
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 2
Index entries leading here 1
- Hydrarthrosis — see also Effusion, joint
- intermittent M12.40
Alongside this code 9 same parent — M12.4
M12.41 Intermittent hydrarthrosis, shoulder category M12.42 Intermittent hydrarthrosis, elbow category M12.43 Intermittent hydrarthrosis, wrist category M12.44 Intermittent hydrarthrosis, hand category M12.45 Intermittent hydrarthrosis, hip category M12.46 Intermittent hydrarthrosis, knee category M12.47 Intermittent hydrarthrosis, ankle and foot category M12.48 Intermittent hydrarthrosis, other site M12.49 Intermittent hydrarthrosis, multiple sites
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.