A German farmer who received the world's first complete double arm transplant is recovering well and able to perform some basic tasks, though doctors said Wednesday it still could take up to two years before he relearns how to use his hands.

Doctors spent 15 hours on July 25-26 grafting the donor arms onto the body of 54-year-old Karl Merk, who lost his own just below the shoulder in a farm accident involving a combine six years ago.

"These are my arms, and I'm not giving them away again," Merk said at a news conference at the Munich University Clinic where the operation was done.

Click here to see Merk's new arms.

It took five teams of medical professionals — a total of some 40 surgeons, anesthesiologists, nurses and other helpers — to carry out the operation. Merk said that when he first woke up, he could not believe it had been carried off successfully.

"It was really overwhelming when I saw that I had arms again," he said. So far, Merk can perform simple tasks with his new appendages — using them to open doors and turn lights on and off.

Doctors said there were good indications of nerve growth in the arms, but that it could still take up to two years before his hands could be usable. At the moment, Merk said he was just looking forward to going home, which doctors said could be in four to six weeks.

During that time he will have to continue an intensive program of physiotherapy, electric stimulation and psychological counseling. There is also still a risk that Merk's immune system will react to the new appendages, though doctors said so far there was no sign of them being rejected.

"The feeling is indescribable," Merk said of "being whole again."

Merk showed off his arms, which are being supported by special "corsets" while the healing continues. "Everyday I gain more mobility."

Merk lost both arms six years ago during a farming accident.

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