It seems there MMA fighters tend to get injured for longer periods of time. Ive noticed the MMA fighters are more likely to get KOed, be unconscious from chokes, and have deeper cuts. While Boxers tend to finish ehe fight in either TKO or decisions and only have bruises.
There's more ways to get injured, that's why. Kicking, Punching, Grappling - There's endless possibilities when it comes to potential injures. Boxing doesn't have that much of a problem compared to MMA in general.
It really depends...... There are still guys from the very early days of the UFC hanging around, and holding their own. The newer guys tend to overtrain, and they get injured more as a result.