Manipulator of bones of the big toe fractured on track (9)
I believe the answer is:
osteopath
'manipulator of bones' is the definition.
(I've seen this before)
'big toe fractured on track' is the wordplay.
'big' becomes 'os' (abbreviation for oversize).
'fractured' indicates an anagram.
'on' means one lot of letters goes inside another (as in clothing 'on' a person).
'track' becomes 'path' (synonyms).
'toe' with letters rearranged gives 'teo'.
'os' placed within 'teo' is 'osteo'.
'osteo'+'path'='OSTEOPATH'
'of the' acts as a link.
(Other definitions for osteopath that I've seen before include "Shot a poet (anag.)" , "Bone manipulator" , "Therapist who manipulates and massages" , "Bonesetter" , "One giving treatment" .)