Doctors say they're satisfied with the condition of a cave researcher hauled out of Germany's deepest cavern after sustaining head injuries, though he will need a few months to recover fully.

Germany Cave Rescue

A rescuer rappels in the the Riesending cave system in southern Germany. Johann Westhauser has been stuck a kilometre underground there since Sunday. (Markus Leitner/Bayerisches Rotes Kreuz/AP)

Johann Westhauser was flown to the Murnau Trauma Center following his rescue from the Riesending cave Thursday, nearly two weeks after being hit by a falling rock.

Doctors said Friday the 52-year-old suffered skull and eye socket fractures, and some internal bleeding. In a video shown at a news conference Friday, Westhauser appeared to have some difficulty speaking but the hospital said he won't need neurological surgery.

Medical director Volker Buehren said Westhauser likely will stay two to four weeks at the clinic, then will need further therapy — with the healing process lasting three to six months.

Rescuers began their work early Thursday morning after resting overnight. They brought Westhauser the final 180 metres to the surface just before noon, Germany's mountain rescue service said.

A fit expert could scale the distance from the site of the accident to the entrance in about 12 hours, but rescuers had to haul Westhauser on a stretcher through the challenging terrain. The entrance to the cave is on a mountainside, some 1,800 metres above sea level.

Westhauser was initially treated by medical experts outside the cave.