Multiple open fractures of the tibia and fibula. Pilon (crush injury) where the tibia breaks into the ankle cartilage. Compartment syndrome (again common with crush injuries) where surgery to the skin, fat, and muscle to relieve pressure had to be done quickly or he could have lost his leg. There might have also been soft tissue damage to the knee, but my guess is the ankle bore the brunt.
It was a really grusome injury. The soft tissue damage can literally take 3+ years for the pain to calm down. Long term arthritis will set in and his ankle will be pinned.
So yeah, Tiger isn't faking. He is in a great deal of pain. Every time you see him standing, all his weight is on his left leg. He probably isn't even aware of that. He needs to keep playing golf and working it. But even when it is as good as it gets, he will have very little strength and range of motion to push/transfer his weight on his swing.