What can we do about this?

My husband recently got his leg injured (hes in the marine corps btw), it was soft tissue damage on his entire calf area. Now the doctors said 7 days light duty. Last time my husband had an injury, as soon as the light duty request was up they expected him to perform at full strength when in reality he was in a lot of pain. He is afraid it is going to happen again, his superiors, he says, do not care for the welfare of others, when he got hurt last time and still requested to be able to use crutches, they said he was malingering. What can we do if this happens again? Do they really have the "legal ability" to make him hobble around on a still badly hurt leg?