Thanks Chloe, that sounds interesting. The orthopedist I've seen today was very skeptical and told me whatever there is, will show in a good, standard MRI (which sounds counterintuitive to me. I've come to mistrust doctors, unfortunately). He just believes in his 3 Tesla machines. (My scan back in January was done probably with 1.5 Tesla). Anyway, I will call that center, which does those unconventional MRI's and ask them how they do it, and will have your description in mind. Thank you.
And if that somewhat arrogant MD I've seen today will not prescribe the positional MRI, I should get it from my genuinely sympathetic GP. I will need a doctor's letter to have it done, I believe.