If you have the insurance, you can call the United Family or Parkway numbers (easily google-able) and get set up with an appointment.
Jiahui is a good private alternative that is covered by a lot of insurance plans that don’t allow for “high cost” providers such as Parkway. (https://www.jiahui.com/en).
For a public option, I’ve also been fairly pleased with the service at Huashan Hospital’s VIP section (called “Worldwide Medical Ceter”, 15th floor of building 6)
Beyond that… before venturing into any of the lower cost public hospitals… considder self amputation. Probably less painful.