Bunion pain can be caused by diseases such as onychomycosis, bunion, rheumatoid arthritis and so on. 1. Inguguinitis: If it is acute, it may be related to bacterial infections such as Pseudomonas aeruginosa and Staphylococcus aureus. In the case of chronic onychomycosis, it may be caused by Candida albicans infection. The patient’s toes will appear red, swollen, hot, painful and other manifestations, so when you touch the foot thumb pain. 2. Bunion: The etiology of this disease is still unclear, and may be related to heredity, bad shoe-wearing habits, congenital foot structure abnormalities, age and other inflammatory diseases. The main manifestation is bunion deformity. If the deformity is serious, it will hurt when touched. 3. Rheumatoid arthritis: this disease may be related to heredity, autoimmunity, microbial infection and other reasons. It is usually characterized by joint pain and pressure pain, which often occurs in the palms of the hands and fingers, but also occurs in the toes, so some patients have the symptom of pain at the touch of the big toe. There are many causes of bunion pain, so you should go to the hospital to get a clear picture of the cause of the problem.