The Queen went to an extraordinary effort to give a poignant "last salute" to well-wishers who packed the Mall to celebrate her 70-year reign, it has been claimed.
The 96-year-old flew by helicopter from Windsor Castle to Buckingham Palace for the celebrations in June last year.
There was a meticulously orchestrated plan put in place to ensure she was not seen using a wheelchair on the balcony in June last year.
The revelations come in a book by veteran royal correspondent Robert Jobson, released this week.
"On her insistence, a military-style exercise was put in place so that no one could see she was having to use a wheelchair," the book states.
"In considerable discomfort, Her Majesty was taken by wheelchair to the helicopter pad at Windsor.
"At the Palace, she was wheeled right up to the balcony doors, then helped to her feet so that she could stand - with the aid of a walking stick - alongside Charles and Camilla, plus William and his family.
"After a firework display, the Queen smiled with delight. It was her last salute to her people."
The monarch dazzled in her emerald green outfit on the Buckingham Palace balcony, the joyous culmination of last year's Platinum Jubilee.
Photographs of a delighted Queen walking gingerly out onto the balcony before waving to the jubilant crowd are among Platinum Jubilee's most iconic images.
She later issued a moving letter to the nation in which she declared: "My heart has been with you all."
But her attendance at the triumphant finale of four days of festivities had, however, hung in the balance for days.
After joining her family on the balcony to witness a spectacular RAF fly-past on Thursday June 2, she was unable to attend a thanksgiving at St Paul's Cathedral the following day after suffering discomfort.
The service was dominated by the attendance of Prince Harry and Meghan, making their first joint royal appearance since quitting their duties.
The Queen had made it clear her presence at events of personal significance, such as the Commonwealth and Cenotaph services, should not come at any cost, it was revealed last year.
In particular, Palace aides were anxious not to replicate a photograph of the Queen's late sister, Princess Margaret, in a wheelchair, six months before she died.
"It's a haunting image and not one the Queen remembers fondly," a source told Mail on Sunday.
Mr Jobson's book also reveals that during the final years of their lives both Queen Elizabeth and Prince Philip had seen Charles more often and grown close to him.
Once well-placed source says there was, in particular, a deepening of the relationship between Charles and his father.
"Over the last year of Philip's life, they were the closest that they had ever been," a member of Charles's close circle of friends had said.