ICD-10-CM > M00-M99 > M65-M67 > M66 > M66.8 > M66.85 M66.85 Spontaneous rupture of other tendons, thigh Non-Billable/Non-Specific Codes M66.851Spontaneous rupture of other tendons, right thighM66.852Spontaneous rupture of other tendons, left thighM66.859Spontaneous rupture of other tendons, unspecified thigh