Helena carelessly holds back stick (4)
I believe the answer is:
cane
'stick' is the definition.
(I know that cane is a type of walking stick)
'helena carelessly holds back' is the wordplay.
'holds' indicates a hidden word.
'back' shows that the letters should be reversed in order.
'enac' is hidden in the letters of 'helena carelessly'.
'enac' reversed gives 'CANE'.
(Other definitions for cane that I've seen before include "Kind of sugar?" , "Flog" , "Hollow jointed stem of, say, bamboo (4)" , "Malacca, perhaps" , "Walking stick; punish" .)