Hi welcome  to HCm    
I have gone thru your query  regarding  painful pulsating on collar bone after doing intense cardio exercise  , is indeed a matter of concern . 
Dear , for your info , our body works well  ,till  it is not broken  and repaired  .
A repaired  part  , that too  with a metal plate,  can 't tolerate  jerks  of increased  amount of intense cardio exercise so  ,you face  painful pulsating  and other problems . 
The strong immune system , which is helpful for our disease free total  health , is incredibly complex because your body  has many lines of defense to rid itself of foreign invaders. 
Modification in your life style , food habits , with required  work out  , 
Yoga , pranayam  deep breathing , are the piller of our strong immune system responsible for healthy disease free life  
 Be careful , not  to  indulge  in heavy workouts  which may harm  you further .  
  To give resistance from  diseases & alley pains take  a level  spoon of turmeric powder with hot  Milk + a spoon of  almond  oil  , at bed time . 
Lemon juice with water , a pinch  of  salt  and  pepper  before meals .
Aloe vera  juice  + Amla
It is suggested to consult your doctor for proper guidance if problem persist
Hope this helps solves your query .Take care .All the best .Get well soon
Don't hesitate to come back in case of any further query .