Hi, Parathyroid surgery is done in neck. The recurrent laryngeal nerve is very near the parathyroid glands and this the cause of hoarseness can be as follows: During surgery some branches of the recurrent laryngeal nerves can get trauma. - This can be in the form of praxia meaning partial one and there can be a good recovery with time. - In some cases there can be cut of the nerve and needs nerve transplantation. I would advise you the following in such a situation: Consult an ENT Surgeon and get laryngoscopy done to see for the status of vocal cords whether some local oedema, polyp or so, movements of the vocal cords. This will give the proper diagnosis and gives proper direction to the further treatment as per the cause found. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. T. Chandrakant, ENT & General Surgeon