“…In primary sporadic cases, the family history is negative, whereas in hereditary cases the family history is usually positive [9]. Secondary causes of CACOL include degenerative cervical spine disease, infection [10], immunological disease [11], hypoxia [12], trauma [13], vascular malformation of the central nervous system (CNS) [14], drugs (olanzapine) [15,16], focal or diffuse brain damage, or chemical agents [16]. The preponderance of females in CD (female:male ratio 2:1) suggests that at least in hereditary cases maternal inheritance of mtDNA mutations could play a causative role.…”