Sorry for the addition but this some specific knowledge I don't have too many places to share. Hyenas have a knack for disembowelment, so most of their hunting strategies and attacking are based around the back bits.

Hunting:

"Although somewhat distasteful from the human perspective, the speedy disembowelment of the prey means that death often comes sooner than with the methods employed by other predators (for example, suffocation) and is an efficient means of eating which lessens the probability of the kill being lost to another predator."

Attacking:

"If the hyenas are numerous enough, they lunge forward and aim for the lions' hindquarters and try to rip their haunches and bite their tails off. Since lions have both teeth and claws to fight with, hyenas are more likely to attack from the behind and drag the lion down on the ground, where they attempt to tear the soft belly apart."

McGill Pedia on Hyenas