I suppose if Buddha need a massage for back pains , you will understand it is unbearable . No need to look for pali word as an excuses or reasons for that escaping isnt it . 
thats not actually very helpful and I have no idea what you mean by the comment tbh.
More insightful than you might have intended. A rock does not feel pain. A sentient being who has no thoughts does not experience pain in the normal sense either.
I don’t even like using these words in the same sentence but I don’t think, Arahants are in any way zombie like. I think they experience much more clearly than you or I, ‘nimmala’ I should say.
Experience comes in basically three flavours, sukha, dukkha, adukkhamasukha.
I think, an aversive mind is always a dukkha experiencing mind, but a dukkha experiencing mind does not have to be aversive.
Please note, dukkha is only used above in the sense of Vedana.