The Duke of Edinburgh has been admitted to hospital for hip surgery, Buckingham Palace has announced. The 96-year-old arrived at King Edward VII Hospital in London this afternoon ahead of an operation tomorrow. It involves a problem with his hip that has been troubling him for around a month, the Telegraph understands. The Queen, who is at Windsor Castle for the traditional Easter Court, is being kept fully informed about the treatment. The Duke, who has retired from royal duties, has been absent from various events in recent days, most recently the Easter Mattins Serviceat St George’s Chapel, Windsor Castle on Sunday. He also missed the annual Maundy Service at Leicester Cathedral last Thursday because of his hip problem, despite being named as a guest in the order of service. Last week, he pulled out of an official engagement with the Queen and Duke of York because he was unwell, according to reports. However, he was spotted driving in Windsor Great Park on Wednesday. The Duke has been admitted to hospital with various ailments over the years including bladder infections, a blocked coronary artery and for abdominal surgery. He was last admitted last June, after becoming ill with an infection arising from a pre-existing condition. He spent two nights at the King Edward VII hospital as a precautionary measure on the advice of a doctor. Peter Kay, professor of orthopedics at Manchester University and a council member of the Royal College of Surgeons, said the most common reason older patients were admitted for planned hip surgery was for a hip replacement, usually due to osteoarthritis or a fracture. He said between one and two percent of hip replacements were performed on people in their 90s and that the mortality rate had halved in the last few years to just 0.25 per cent. “It is a relatively safe procedure,” he told The Telegraph. “You have to make sure the patient is fit and well but generally speaking, you will be in hospital around five days and spend six to eight weeks using crutches before walking independently and carrying on with normal life.” The Queen Mother underwent a hip replacement on her right hip at the same hospital in 1995, at the age of 95, and another, on her left hip, aged 97, in 1998. Other planned hip procedures include a partial hip replacement or treatment for other illnesses such as cancer or an infection. The Duke retired from royal duties last August. Buckingham Palace stressed that the decision was not health-related and that he had the full support of the Queen.