Mountaineer with surgical rod in a heel (8)
I believe the answer is:
alpinist
'mountaineer' is the definition.
(I've seen this before)
'surgical rod in a heel' is the wordplay.
'surgical rod' becomes 'pin'.
'in' means one lot of letters goes inside another.
'heel' becomes 'list' (I've seen this in other clues).
'a'+'list'='alist'
'pin' placed into 'alist' is 'ALPINIST'.
'with' acts as a link.
(Other definitions for alpinist that I've seen before include "mountaineer" , "one climbs" , "Maker of sharp climb" , "Climber of big mountains" .)