What Does Swelling Around The Knuckles Indicate?

Sure, i ll give it a shot... Broke my right clavicle in a biking accident 9/7/17. Had related surgery; now healing. MY QUESTION, HOWEVER, IS ABOUT MY LEFT HAND. Approx 3 days post-crash, I noticed swelling around my knuckles, and a general (light) soreness of the back of the hand (as if I d bruised it). Movement was not impaired, however. In the weeks since, that general soreness seemed to migrate to the lower digits of my fingers, and became a bit painful as I gripped items strongly. If someone shook my left hand firmly (for the right is in a sling for the clavicle), it d actually cause me to wince. I had three x-rays of the hand - all negative. Upon further investigation (self-poking, prodding, squeezing), the most painful spot seems to be in the soft tissue near/between the knuckle of the middle and pointer fingers. Is this likely acute tendonitis, or what else should I consider? The hand has grown considerably weaker over the 3.5 weeks (no improvement). THANKS.