M66.26
Spontaneous rupture of extensor tendons, lower leg
Not billable — category only FY2026 2025-10-01 → 2026-09-30
Exclusions 12 never code together
M66code
Excludes2
- rotator cuff syndrome (M75.1-)M75.1-
- rupture where an abnormal force is applied to normal tissue - see injury of tendon by body region
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
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 2
Index entries leading here 1
Alongside this code 9 same parent — M66.2
M66.20 Spontaneous rupture of extensor tendons, unspecified site M66.21 Spontaneous rupture of extensor tendons, shoulder category M66.22 Spontaneous rupture of extensor tendons, upper arm category M66.23 Spontaneous rupture of extensor tendons, forearm category M66.24 Spontaneous rupture of extensor tendons, hand category M66.25 Spontaneous rupture of extensor tendons, thigh category M66.27 Spontaneous rupture of extensor tendons, ankle and foot category M66.28 Spontaneous rupture of extensor tendons, other site M66.29 Spontaneous rupture of extensor tendons, multiple sites
Subordinate codes 3
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.