Hi thanks for your question
Your son is having fractur dislocation with infection of left arm(could be osteomylitis of humerus
).This is a complicated problem and needs to be delt by a specialist.Your son has 3 differnt issues .Off all the three,dislocation is most easy to manage,which can be reduced under General anaesthesia
.Fracture can be managed in two ways.If there is no infection of humerus,open reduction and internal fixation
can be done,but if there is infection of humerus ,fracture has to be reduced and fixed by external fixator and bone infection
is treated simultanously.I would suggest you to consult an orthopedic surgeon who will be able to manage all the three problems of your son.Hope this answers your question.