Hello. Welcome to hcm.
There might be a residual injury still in kidneys or the fracture in ribs might still be in the process of healing.
I advice you to get a ct scan
done to rule out kidney pathology persisting due to injury. Also blood tests like urea and creatinine
to see the function of kidneys. If normal,it might be due to stretching of capsule around kidney and slowly pain will go down.
If rib fracture
was present,then it takes time to heal. You can visit physiotherapist for exercises and heat therapy
to decrease pain sooner.
All the best