ICD-10-CM > M00-M99 > M65-M67 > M66 > M66.8 > M66.87 M66.87 Spontaneous rupture of other tendons, ankle and foot Non-Billable/Non-Specific Codes M66.871Spontaneous rupture of other tendons, right ankle and footM66.872Spontaneous rupture of other tendons, left ankle and footM66.879Spontaneous rupture of other tendons, unspecified ankle and foot