Pain in area having stitches after hair transplant surgery (FUHT). Is arnica beneficial in reducing pain?

See a doctor first.  Preferably your doctor that performed the surgery.  You need an exam before you think about treatment options.Trust the doctor on what tests to order.  It is abnormal to have pain after 3 years.

This pain usually is gone in 1-2 weeks, if not see your doctor again. There is nothing you can do about the pain and the homeopathic approach offers little benefit. I would certainly not go to a neurologist and an MRI offers nothing for this diagnosis. If the pain radiates up into the upper part of the scalp, it might indicate a nerve injury from the surgery, something that is rare in the hands of a good surgeon. Again, speak with your surgeon about it.With regard to PRP, anyone can claim anything. It may be true. I cannot verify the claim that PRP has value. If these treatments do work, you are likely correct in stating that these treatments would be duplicated and offered all over the world – especially because it is such an easy and inexpensive thing to do. By that I mean, in essence, someone takes a vial of your blood and spins it down in a centrifuge to separate out the PRP (platelet rich plasma) from the red blood cells and injects it back to your body part (scalp).I do know many doctors advertise Platelet Rich Plasma PRP therapy and discuss it in terms of regenerative therapy or stem cell therapy which definitely catches the attention of many consumers.I also know that there are many articles and journals that publish positive results of these types of therapy but I have not found one that is truly a well designed research that has been replicated. What I mean by a well designed research, is called a Double Blind Randomized Control Study. When reports come out that you get an 80% improvement, what does that mean? An improvement of what? If we get 90% of the hair to grow without it, does that mean that we can get 98% of the hair from a hair transplant to grow instead of 90% with it? There has never been a study done that shows value. We would have no objection to using PRP and may even do so one day, but as I believe that if a doctor needs to get an 80% improvement of their results by using PRP, then they have a problem in their technique and I would doubt that PRP would help them solve such a deficiency. I have seen doctors inject PRP into the scalp of balding men and women, but they do not do this as a charity, they charge for it, and charge they do. If we start injecting PRP which would be a push, we would not charge for it unless we demonstrated real value.

Usually the first year there may be some discomfort in the stitched area because of stretched tissue.  However this diminishes over time as skin naturally stretches. It is unusual that this discomfort continues for three years.  You need to check with your doctor to find the cause for your discomfort in the back of your head.