Most medical doctors have limited understanding of what chiropractors actually do and even less understanding of what an upper cervical chiropractor does. They think that we will be twisting and popping the spine and they are concerned that we will damaged already weakened tissue. Since upper cervical care places minimal stress on the spinal joints (adjustments are done with the neck in a neutral position) and in many cases not near the area of surgery, the care is extremely safe. A very through examination is done prior to any care to be sure the care will be both safe and effective.
By the way, do you know that chiropractors have the lowest malpractice insurance rates of any profession.