Musannaf Ibn Abi Shayba 18:388

Abu Bakr narrated to us, he said: Abd al-Rahim narrated to us, from Ash'ath, from Abdullah ibn Dhakwan: That Umar judged regarding a man whose leg was broken, then it was set and became straight, so he judged for it twenty dinars. It was said to him: "It has become weak."