MADRID, March 3 (Xinhua) -- King Juan Carlos of Spain on Sunday underwent a successful operation on his back at a Madrid hospital.
The operation, involving two of the king's spinal segments, lasted for around three hours and the hospital's chief neuro-surgeon said the operation had gone "stupendously well."
The doctor added that the king will remain in hospital for around a week and will then need between two and six months to completely recover.
As he arrived at La Milagrosa clinic, the king joked, "Here I am again." He was welcomed by a handful of citizens at the gates, although one carried a banner saying King Juan Carlos was "bad for Spain."
It is the 12th time the 75-year-old king has undergone surgery during his lifetime.
He had a hip operation last November after he broke his hip during elephant hunting in Botswana last April. He was vilified for taking the luxurious trip when his country was suffering a grave economic crisis.
The image of the Spanish royal family has also been tarnished by an embezzlement scandal involving the king's son-in-law Inaki Urdangarin. The case is currently under trial in Palma de Mallorca.
There have been growing calls recently for the king to abdicate in favor of his son Prince Felipe, who is the heir to the throne.
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