Why did Naruto lose an arm, but he stretched it out in 700 words?

Naruto and Sasuke finally had a big fight. After fierce fighting, both sides broke their arms. Woody Sakura and Gang Shou made artificial limbs for them from the cells of the first generation Naruto. You can clearly see that Naruto's arm is bandaged with 700 words, which is a prosthesis.

Naruto:

The hero of the Japanese anime Naruto. Fire nation Muye Yincun Ninja, son of Muhuoying's fourth generation Namikaze Minato, Kyubi no Youko's second generation Uzumaki Kushina, and Ootutuki Hagoromo's second son Asura reincarnated.

When he was born, his parents died to protect the village and sealed the powerful bijuu-Kyubi no Youko in Naruto. Naruto, an orphan, grew up cold-eyed and lonely, but with the encouragement of his only teacher Umino Iruka and three generations of Muhuoying, Naruto made up his mind to become Huo Ying and let everyone recognize his existence. After officially becoming a ninja, he formed the seventh class with Hatake Kakashi, Sasuke Uchiha and Haruno Sakura, and embarked on the road of spiritual practice together.

In order to protect the fetters between himself and his partners, Naruto kept practicing hard, became a closed disciple of Jiraiya, one of Konoha's "three forbearance", and learned his father's homemade Ninjutsu spiral pill, practicing magic, and successfully controlled Kyubi no Youko chakra in his body. After defeating Payne, the Xiao leader who attacked Konoha, Naruto finally got rid of the ridicule of the villagers and became a hero praised by everyone. In the Fourth World Endurance War, he joined hands with Sasuke to fight against the enemy, played a vital role and became a hero to save the world. In the end, Naruto finally realized his dream, became seven generations of Muhuoying, and had a son and a daughter with Hinata Hyuga.