Worries for German Schumacher as he could be in 'vegetative state' forever as he enters 150th day in coma #BringBackOurGirls #Entertain9jar via @myentertain9jar

STRICKEN F1 ace Michael Schumacher spent his 150th day in a medically induced coma amid persistent rumours that he may be in a permanent vegetative state for the rest of his life.

Michael Schumacher, fans' messages and Grenoble University Hospital[GETTY]

Such a condition means that he is conscious but cannot move or communicate.  He has been in the University Hospital of Grenoble since December 29 when he suffered catastrophic brain injuries while skiing in the French Alps.
His management team have not issued an update on his progress for over six weeks.  That last prognosis was that he continues to display "encouraging signs" as doctors continue in their efforts to bring him around from the artificial deep sleep.
But medical experts fear the worst.  Next week he will enter the sixth month of his coma with little perceptible progress to indicate that he will regain full consciousness.
Wife Corinna and children Gina Marie, 17, and son Mick, 14, have been a constant presence at the 45-year-old's bedside.
Dr. Andreas Zieger, chief physician of the clinic for neuro-rehabilitation at the Evangelical Hospital in Oldenburg, Germany, said:  "You can never tell how quickly a patient with a brain injury is going to wake up.  But the longer the recovery phase, one must conclude, means that the brain damage suffered must have been very serious."

Medics have expressed doubts about the recovery of the F1 legend [Bongarts/Getty]

The longer that he is in the coma, the more improbable it is that he will recover from it

Gary Harstein, the former Formula One doctor

Focus Magazine in Munich asked French neurological professor Philippe Azouvi about his recovery chances: "The only thing we can say is that, statistically, 30 percent of patients recover well from a severe brain injury, mild impairment affects 50 percent of them and 20 percent of them suffer from severe disabilities and remain dependent on constant help."
Worldwide, medical experts have questioned whether any recovery will be meaningful.
Gary Harstein, the former Formula One doctor, wrote several weeks ago: "The longer that he is in the coma, the more improbable it is that he will recover from it."
Schumacher, 45, suffered a near-fatal head injury in a skiing accident in Meribel, France, on December 29.
The accident occurred just over 14 feet from the edge of the ski run in an off-piste area in the French resort of Meribel.
He was skiing with his 14-year-old son when he lost control after hitting a rock. He ended up smashing his head into a bolder 34 feet further down the mountain.
He is receiving round-the-clock care in intensive care in Grenoble University Hospital.