How does Wolverine have any flexibility in his wrists and elbows and forearms if his retracted claws are 12 inches long?

Wolverine's retractable claws are housed within his forearms and extend beyond his wrists when he unsheathes them. When retracted, the claws fold up along his forearm bones, so they do not impede his flexibility in the wrists, elbows, or forearms. This design allows him to have normal range of motion when his claws are not extended.