Rehabilitating a dog after getting a broken leg

Just after moving to a new home my wife and I notice that the neighbors had a very noisy labrador retriever that used to bark and mourn constantly. After sone days we visited them realized that the dog was recovering from broken his leg months ago and his owners were afraid of walking him since then (he used to scape from the dog-collar, eventually he was hit by a bus), that is why he was so noisy and anxious. So we volunteer to walk him. We have been doing that for the last weeks and got very happy with our new friend.