"tiny legs" is correct and usable in written English.
For example, you could use it in the sentence "The baby's tiny legs kicked up and down as if she was running."
Her tiny legs dangled like a doll's.
Julian's partridge in a red-wine reduction was succulent, the tiny legs chewily delicious.
He said: "I could see tiny legs and realised they were spiders.
It would wobble on its tiny legs in the face of such orthodoxy.
No - one set of tiny legs twitches for a while, then stops.
The primary rival is a mustachioed man who looks like an egg, prancing on tiny legs.
"Eat with your hands!" Ms. Spyres dutifully picked up and gnawed a tiny leg.
His fingers caught, pulled and broke through whatever was restricting the bird's tiny leg -- and the two birds, now free, took off into the skies above Madison Avenue.
The very features that enable them to soar--leathery wings and tiny legs--make it impossible for most bats to manage more than an awkward crawl on land.
And even today pythons and boas have tiny leg bones inside their bodies, suggesting they have vestiges of the molecular pathway for building these appendages.
The mechanics of this process was mysterious – but if you look carefully at the following video, you can see that at the point of explosion, a tiny "leg" emerges from the kernel that bounces off the plate, propelling the corn from the surface.
