The ER did not catch my husbands broken hip?

My husband feel a couple weeks ago, he could not get up was in terrible pain in his hip. We called the ambulance he was taken to the ER. He was taken to xray which showed nothing. He was is so much pain he was to the point of yelling with each movement it was all in hip area. Instead of looking further into this he was sent home. Could not move for 2 days , we took him to another er where the immediatly did an ct and found a broken hip, by this time it had been 48 hrs after the injury and he developed pneumonia and was hospitalized for a week. What recouse do we have as this er dr did not persue and caused my husband to suffer and and additioanl trauma