Could also be a hot spot, this time of year they seem to get worse. Vet check is good idea. Gold bond powder applied to the area after cleaning with a very diluted listerine,and cutting away the fur is an effective treatment for hot spots.
Just got back from the vet today. Duff has arthritis it not too severe yet but we are giving him supplements as well as some prescribed pain killers. Hopefully these will help diminish the pain and slow down the arthritis. Thanks for all help and comments.