What Fighters can stop

Fighters who chose Combat Superiority(that should nearly be all fighters) can stop movement when an opportunity attack hits. This prevents enemies from just walking away from the fighter.

What Fighters can disincentivize

One enemy from shifting or attacking someone not the fighter.

What can enemies still get away with?

• An enemy can eat a combat challenge attack, shift away, and charge an ally.
• An enemy can attempt to move, get stopped by the fighter, then charge an ally.
• An enemy can still attack allies that it can reach.

How to elegantly prevent enemies from getting away from you

Knock them over, slow them, immobilize them, or follow them with opportunity attacks AND combat challenge attacks using as few feats, powers, Paragon Paths, and Epic Destinies as possible.

Elegance in the Epic Tier:

• Dark Sun Campaign Setting's Arena Fighter background fighters choose the 'Keep Them Close' feat.
• Having already multiclassed into Warden, choose the Perfect Guardian Epic Destiny.

Elegance in the Paragon Tier:

• Tieflings take the feat Tail Trip.
• Greatweapon fighters can take Pinning Challenge and pair it with Tactical Superiority.
• Shield-flail users can take Hindering Shield and Lashing Flail.
• Shield users can take Tactical Superiority and Staggering Challenge.
• Gladiator Champion Paragon Path level 16 disallows enemies from shifting away from you permanently. Combine that with Tactical Superiority.

Elegance in the Heroic Tier:

1. Take the Mobile Challenge feat to pursue enemies that shift away.

2. Choose a method to prevent move-charge escapes:

• Brawler fighters are set with Grappling Strike.
• Warforged choose Warforged Superiority.
• Minotaurs choose Opportunity Gore(does not scale well).
• Shield users take the Tide of Iron at-will power and the Bloodhound Style feat. Then use Tide of Iron on your turns to slow the enemy. It's boring, but effective.
• Else multiclass into Warden to qualify for the Sudden Roots feat.

How to prevent an enemy from attacking allies it can reach

Use a push, pull, or slide to move them out of reach of your ally. An attack with an invalid target fails, wasting the attack action.

Paragon Tier:

• Flail users get Lashing Flail.
• Everyone else cries.

Heroic Tier:

• Shield users get Shield Push. I recommend also getting Mobile Challenge so as not to push the enemy out of your own reach or it can take an unimpeded move action.
• Everyone else cries.

Combining it all together

• Guardian Fighters:

Use a one-handed flail and a shield. Choose an Arena Background. Heroic Tier: Take Mobile Challenge, Shield Push, multiclass warden, and Sudden Roots. Paragon Tier: Retrain Shield Push into Lashing Flail. Retrain Sudden Roots into Hindering Shield. Retrain multiclass warden into anything. Epic Tier: Retrain Hindering Shield into Keep Them Close. Retrain Mobile Challenge into Mobile Warrior(Not required, just a good mobility boost).

• Great Weapon Fighters:

Heroic Tier: Take Mobile Challenge. Multiclass into Warden and take Sudden Roots. Cry that guardian fighters are better in the heroic tier. Paragon Tier: Retrain Sudden Roots into Tactical Superiority and discard multiclass Warden. Either retrain Mobile Challenge into or also take Pinning Challenge. Start using a two-handed flail and take Lashing Flail. Epic Tier: Retrain into Mobile Warrior.

• Brawlers:

Take Mobile Challenge. Cry that guardian fighters are better in the heroic tier. Use a one-handed flail and get Lashing Flail at paragon tier. Retrain Mobile Challenge into Mobile Warrior at epic tier.

• Tempest Fighters:

Heroic Tier: Take Mobile Challenge. Multiclass into Warden and take Sudden Roots. Cry that guardian fighters are better in this tier. Paragon Tier: Use two scourges and get Lashing Flail. Retrain Sudden roots into Tactical Superiority to free up your multiclass slot. Epic Tier: Retrain Mobile Challenge into Mobile Warrior.

• Arena Talent Fighters:

Use a spiked chain, you choad. Take Mobile Challenge, Sudden Roots, and then cry. Upgrade Sudden roots into Tactical Superiority. Get Lashing Flail. Retrain into Mobile Warrior.

Alternatively, use a spiked shield and 3-headed flail and pretend to be cool like a Guardian Fighter.