LATEST: British monarch Queen Elizabeth II has been forced to cancel another public appearance due to persistent back trouble. The 80-year-old sovereign, known for her love of equestrian events, missed the annual horse races in Newmarket, eastern England, yesterday (27OCT06). The monarch enjoyed a luncheon in her honour at the event but did not stay for the races themselves. A spokeswoman from her official London residence Buckingham Palace explained, "There will be no standing around. Doctors are taking it on a day-by-day basis". On Thursday (26OCT06) the Queen was forced to pull out of opening the new Emirates Stadium of soccer club Arsenal in north London after hurting her back during her recent trip to the Baltics.