Hi. Thanks for your query. Noted the history and understood the concerns. Throat pain for 8 years and close up of throat while walking up the steps with normal X-rays and MRI and inability of the Doctors to find out the cause may be due to the following reasons: Condromalasia of the thyroid, hyoid, crickoid and tracheal cartilages. Or some neurological affection. Or due to asthma of respiratory or cardiac origin which is overlooked due to minimum of evidence or complaints. I would advise you to take your Mother to the ENT Surgeon and discuss all these points and have ENT endoscopy and clinical evaluation and second opinion of a Neurologist, cardiac and respiratory checkup. This may find the caused a she gets a proper management. In the meantime give her multivitamins, calcium and Vitamin D3.