Late Pay raise

When my husband started his job in july 2006, he was told that after 90 days he would get a pay raise. Then in Sept he was injured at work. In Oct when he was supossed to receive his raise he didn't. He was not even given an evaluation. As he thought that it was because of his injury and the fact that he was on light duty, he did not ask for it. After he was back to working full duty for at least a month, he asked about his supervisor about his raise. He was told that he would take care of it. During this time, people that had started after him had been given their raises.Six months after he was original supossed to receive is raise, after many requests and even a letter, his supervisor finally gave him his evaluation and he received a 50 cent raise. Is he entitled to back pay for the raise he did not receive.

Yes if it was guaranteed and agreed to be given.