Can stuttering be caused by emotional trauma or head surgeries? No matter how many specialists I see I can't shake my severe stutter. 

Stuttering biologic? I'm not an expert in this area but a psychiatrist i knew treated himself successfully with a newer antipsychotic medication. This off label use has many risks & highly recommend other attempts with relaxation and antianxiety medications first. But a low dose of a second generation antipsychotic might be worth a try in severe stuttering. This may be a clue that stuttering is a movement disorder.
Stuttering. I understand there is a medical device which is effective with some individuals and consists of wearing headphones that reproduces whatever the user is saying, only very slightly delayed. That way, the stutterer hears what they say and can make changes in their speech.