Updated

King Juan Carlos of Spain has left a hospital six days after successfully undergoing surgery for herniated discs in his lower spine.

The 75-year-old monarch thanked waiting journalists for their patience and said "I'm very well, my back doesn't hurt or anything," from the front passenger seat as he was driven home Saturday.

The operation was the head of state's fourth in 12 months, and the 12th time he has undergone surgery during his lifetime.

Juan Carlos had hip surgery in November and other health issues in the last two years, including needing knee surgery and the removal of a benign lung tumor.

It has been an awkward year for the king, whose son-in-law, Inaki Urdangarin, is under investigation on suspicion of having embezzled several million dollars.