Craig Gardner's appalling tackle was violent and aggressive, despite what the clogger says himself, it was clear that there was no need for him to follow through with his non tackling leg, this aspect of the tackle was vindictive and malicious. Arsene said in his statement:
"The injury is in exactly the place where he got kicked against Birmingham and he has a crack on his bone."
This makes it likely that Cesc's leg was actually broken by Gardner, it was simply that it was such a subtle break that it was not detectable on the X-Rays, as some fractures are. He has been in a lot of pain since the Birmingham game and was only 40% to start, he then never looked fit against Barca and was labouring throughout, it is unlikely that bruising would have done this. Cesc probably had a small crack in his fibula that was more obvious on the X-Rays after the Barca game. The Puyol tackle was innocuous and low energy, I find it hard to believe that this cracked the bone.
The fact that this break was probably missed doesn't matter to Cesc, it is a stable injury that won't affect him in the future, it will simply be too painful to play on with the pain. It also doesn't reflect badly upon the medical staff, these things happen in medicine, X-Rays aren't perfect, nothing in medicine is, that's life, unavoidable error is everywhere. This 'missed leg break' story shouldn't be hyped up into something it is not, the fact that the injury was missed is really not a particularly interesting story if one has a bit of an understanding of legs.