ollow ▁core . ▁ ▁After ▁this , ▁secondary ▁neural ation ▁occurs ▁in ▁which ▁the ▁med ull ary ▁cord ▁begins ▁to ▁form ▁and ▁is ▁filled ▁with ▁many ▁cav ities ▁that ▁ultimately ▁form ▁the ▁l umen . ▁The ▁cav ities ▁formed ▁from ▁the ▁initial ▁and ▁secondary ▁neural ation ▁combine ▁to ▁form ▁one ▁un inter rupted ▁cav ity . ▁There ▁is ▁still ▁spec ulation ▁on ▁the ▁formation ▁of ▁the ▁ca ud al ▁cell ▁mass ▁in ▁humans ▁with ▁arguments ▁being ▁made ▁for ▁it ▁ar ising ▁from ▁many ▁cav ities ▁or ▁the ▁continu ing ▁growth ▁of ▁the ▁ne uro ce le ▁from ▁the ▁initial ▁neural ation . ▁The ▁ca ud al ▁cell ▁mass ▁will ▁ultimately ▁differenti ate ▁and ▁form ▁into ▁many ▁sac ral ▁structures ▁such ▁various ▁n erve ▁end ings ▁and ▁the ▁con us ▁med ull aris . ▁ ▁Ro le ▁in ▁D ise ase ▁ ▁The ▁ca ud al ▁cell ▁mass ▁plays ▁a ▁role ▁in ▁many ▁dise ases ▁and ▁ab normal ities ▁related ▁to ▁the ▁sp inal ▁cord . ▁One ▁group ▁of ▁ab normal ities ▁it ▁plays ▁a ▁role ▁in ▁are ▁occ ult ▁sp inal ▁d ys raph isms . ▁These ▁types ▁of ▁ab normal ities ▁arise ▁from ▁specific ▁structures ▁formed ▁in ▁the ▁ca ud al ▁mass , ▁for ▁example ▁if ▁proper ▁different iation ▁of ▁the ▁ca ud al ▁mass ▁does ▁not ▁occur , ▁it ▁could ▁result ▁in ▁a ▁type ▁of ▁sp inal ▁d ys raph ism . ▁One ▁example ▁of ▁sp inal ▁d ys raph ism ▁is ▁ca ud al ▁regression ▁synd rome . ▁Pat ients