An item of underwear sold in outrageous new style initially causes injuries (9)

'injuries' is the definition.
(abrasion is a kind of injury)

'an item of underwear sold in outrageous new style initially' is the wordplay.
'an' becomes 'a'.
'item of underwear' becomes 'bra' (bra is a type of underwear item).
'initially' indicates taking the first letters.
The first letters of 'sold in outrageous new style' is 'sions'.
'a'+'bra'+'sions'='ABRASIONS'

'causes' acts as a link.