your best bet would be to start looking at your activities of daily living? what is your occupation?
if you are scoliotic, then your cervical spine will have to also adapt to below changes in the chain, you might have a forward head with regards your posture...
when the headache starts? what relieves it...
These muscles generally overwork when you have a forward neck posture and the deep flexors of your neck are weak, they take up the role of stabilizers, something they are not used to...so the begin to ache...
cervicogenic headaches, several theories to the cause, some say trapped nerves with muscle, others say within the upper cervical joints...
exploring your activities of daily living and occupation may give some insight into predisposing factors...its one thing to get treatment that helps temporarily, its another to maintain effect gained...
an understanding of your general posture is necessary, and if anything at all, working the deep flexors of your neck is necessary...
Ask yourself if you have the adequate support for your head and neck when you sleep...or what your sleeping position is like....
Do you get any aura (blinding flashing lights or colors) when this headache comes?
T