Perhaps looking over your Medical Questionnaire. In all those "yes" "no" boxes you
might have marked "yes" to any question about chronic neck & back pain. I've been at MEPS when it seemed to take an act of G-d to make the MEPS staff understand that the prospective recruit marked the form incorrectly. A hundred years ago (17 but who's counting) when I went to MEPS the recruiter actually had us DEP'ers fill out these questionnaires over and over again at his office to avoid what you're going thru....if that is the case with you.
The MEPS philosophy is you filled the form and signed it verifying the info was true & correct. Once you are disqualified, now you want to change your answers. It's akin to failing a math test and then telling the professor you didn't mean to write that answer down......it's too late. Most of the disqualifications I've seen are based on what the candidate checked off. The staff can only go based on what you tell them and put on the form.
Since the reason, you presented, for your disqualification seems benign I would work to get it resolved. Just.....be careful what you wish for.