Hi Tony, sorry to hear about your bad luck and I hope your back feels better soon. My thread on the diabetes board 'Unexpected High Number!' posed a similar question regarding high numbers and stress and it seems that it can and very probably will raise your bg levels, and if you are tensing your back muscles to relieve your back pain that may well keep your numbers elevated.
Hot/cold gel packs from chemists like boots really help me with my long term back pain. I wish you a speedy recovery.