Abuse Stradivarius, perhaps, and trombone’s case (7)
I believe the answer is:
violate
'abuse' is the definition.
(I've seen this before)
'stradivarius perhaps and trombone's case' is the wordplay.
'stradivarius perhaps' becomes 'viola' (string instrument made by Stradivarius).
'and' means one lot of letters go next to another.
'case' suggests removing the centre.
'trombone' with its middle taken out is 'te'.
'viola'+'te'='VIOLATE'
(Other definitions for violate that I've seen before include "Infringe; defile" , "Break in on; disregard" , "Rudely disturb" , "Desecrate, despoil" , "Abuse" .)