Found these pics at HJL Korean fansite.
As I tweeted, HJL was actually still in pain during Dream Concert 2010, yet, he took pain killer so he could perform U_U See his pain expression along the photo spread >.<
Credit goes as tagged! More under the cut!
슈퍼스타 501 영원히!! 
Swollen face ,immobile right arm ,right shoulder looks stiff and facial expression and eyes cannot deny the pain while performing .Hyun Joong ,I salute your sense of professionalism ,You are now an icon and role model of the junior performers . You are now a true Sunbae of entertainment Korea.