These days you have these options:
Stormraider's, which is horrible on almost every juggernaut (maybe it can work on Illaoi and Darius)
Grasp: You become a meatshield. It's boring, it's not fun, and it doesn't feel like a Juggernaut. It feels like a tank, and it's boring as all hell, but it has the most success.
Aftershock: Used vs fast trading matchups (Riven best example) where you abuse E. Really conditional, but is pretty fun
PTA/Lethal Tempo: The problems with these are that they just take too long to apply. Even in lane, it's hard to stick onto most targets for long enough to trigger them effectively and consistently. Lategame, there is no way to reliably trigger them, and most juggernauts rely on their abilities rather than AAs post laning phase as well.
Glacial: It has similar problems with PTA/Lethal. Not exactly the same, but similar.
Electrocute: It's honestly better than PTA/Lethal if you want to go aggro, but the rest of the tree isn't super great on most juggernauts, and it also lacks attack speed. Juggernauts tend to want extended trades, rather than the short bursts of electrocute. The high CD also sucks
Predator: You high? It's fun, but please don't.
Fleet Footwork: It sorta feels ok in lane but it's bad lategame. Worst of both worlds.
So the main ones you have are: Grasp, and conditionally Stormraider's/Aftershock.