Busy working, he got injured (2,3,2)
I believe the answer is:
on the go
'busy' is the definition.
(similar in meaning)
'working he got injured' is the wordplay.
'working' becomes 'on' (e.g. a machine is working or on).
'injured' indicates anagramming the letters.
'he'+'got'='hegot'
'hegot' with letters rearranged gives 'thego'.
'on'+'thego'='ON THE GO'
(Other definitions for on the go that I've seen before include "Very busy, in constant motion" , "Ever busy" , "Active, in constant motion" , "Busy and active" , "Active and energetic" .)