can you tell me his FBS,PPBS and HbA1c
level which can give me some idea abt the problem. is he a smoker . and ist the leg or the toes. is he having loss of sensation in the legs . if he is a smoker if the sugar is not well controlled the best thing to get your doubt cleared is do a Doppler scan of the legs to know the arterial flow and to rule out any narrowing or block in the arteries . the pain may be due to reduced blood supply so don't delay and do a Doppler get rid of your pain.
expecting your feed back . good luck take care