Since the Other Expert has opted out , I would be please to answer your question.:
There are three possibilites:
The warts which you are mentioned may be:
1.Acne Keloidalis Nuchae: these can look like wart like growths. .These as you mentioned can occur as you have mentioned which are formed by the hair growing inwards complicated by excess growth of tissue . These are removed with intralesional steroids along with a combination treatment of laser hair removal
to remove the hair. The Keloidalis word is just a misnomer and does not mean that you have keloid
2. Skin tags: These are excess of the skin which are commonly seen on the back of the neck. They are removed by radiofrequency method where a pen like instument is used to pass a mild current to cut the skin tags. It was a scab on the area which last for 5 days and then the skin heals normally without leaving behind any mark.
3. Pseudofolliculitis barbae
: These as you mentioned can occur as you have mentioned which are formed by the hair growing inwards.Very unlikely to occur at the back or nape of the neck. They are removed by Laser hair removal technique using Laser.
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