What Causes Swelling And Discolouration After A Fall?

my husband is in his fifties and is overweight. His family members all have diabetes and he fell a few years ago. After falling, his leg swelled and turned purplish black. Periodically the leg feels warm to the touch and lately is swollen most of the time. He saw a doctor after falling and was told not to be alarmed that the blood had build up and was not circulating. Can you please tell us your thought on this matter?