Left university doctor with earlier condition ... (7)
I believe the answer is:
lumbago
'condition' is the definition.
(I have seen 'Painful condition' mean 'lumbago' so perhaps 'condition' could also mean 'lumbago')
'left university doctor with earlier' is the wordplay.
'left university' becomes 'lu' (this might be a standard abbreviation of which I'm unaware).
'doctor' becomes 'MB' (Bachelor of Medicine, Medicinae Baccalaureus).
'with' is a charade indicator (letters next to each other).
'earlier' becomes 'ago' (I've seen this in another clue).
'lu'+'mb'+'ago'='LUMBAGO'
Can you help me to learn more?
(Other definitions for lumbago that I've seen before include "Back complaint" , "Maul bog badly for a rheumatic affliction" , "Rheumatic pain in muscles of lower back" , "Pain -- a bum log (anag)" , "Rheumatism of lower back" .)