Hi all,
Thanks for all the replies and all your ideas! With regards to investigation, he has not had an MRI yet and he's unable to have one at present - basically his doctor won't refer him on for further investigation until he has had physio [in the NHS] and he's unable to attend any physio appts in the NHS due to work commitments and being unable to get any time off, hence him having some private sessions.
I hadn't done combined movements on testing so will have to assess this when I see him again. To add to my original post, I've been doing massage and focusing particularly on upper traps/cervical musculature as he seems to be very tense and imbalanced around this area. His symptoms have decreased a lot since I've seen him last and he says he feels his pain is settling, not as bad as it was previously even at the end of the day in work (and he's been doing more manual work the past 1-2 weeks).
He's not participating in any sports at the moment, he's tried to return to rugby previously but the neck pain had returned within 10 minutes of starting to play. He goes to the gym about 2-3 times weekly, just on crosstrainer/treadmill, not doing any weights or anything too strenuous (and this doesn't affect his pain).
Was definitely thinking about moving on to scap setting and looking at his shoulder girdle stability and core stability as a whole next. I'm not trained in acupuncture but all your ideas are v helpful! Thanks for the responses. I'll keep you posted on how things progress.