Boxer's fracture

Hi, about 8 years ago, i broke my hand - i broke the 4th and 5th metacarpal bones and mashed my knuckles up…since then I have had some bad post injury symptoms that i want help with.
I find my hand gets cold very easily, in turn hurts…i’m an illustrator so it can really hinder my job.
So i think i have some circulation issues in this hand, also i can literally tap my knuckles on a hard surface and it really hurts…almost like i have broken it again?

When its very hot weather, my hand will swell up - its becoming a nuisance as its an everyday thing…anyone experience this or have any info pls?

Thanks

Nathan