Head left Los Angeles with body part (7)
I believe the answer is:
patella
'body part' is the definition.
(patella is a kind of body part)
'head left los angeles' is the wordplay.
'head' becomes 'pate' (humorous term for the head).
'left' becomes 'l' (common abbreviation).
'los angeles' becomes 'LA' (abbreviation).
'pate'+'l'+'la'='PATELLA'
'with' is the link.
(Other definitions for patella that I've seen before include "positioned on each knee" , "Joint cover" , "bit of body usually under trousers!" , "Kneecap (anatomy)" , "The formal kneecap" .)