Formula 1 - Schumacher's head-cam 'may have acted like hammer on his skull'

The skiing crash that left Michael Schumacher in a coma may have been made far worse by the camera he wore on his helmet, according to an early report from the investigators.

Schumacher was skiing in Meribel at the end of last year when he hit a bump and landed on his head.

French investigators closed the investigation into the crash on Monday morning, coming to the conclusion that there was no wrongdoing by any individual

The full report has not yet been released, however, and there remains speculation over the circumstances of the incident. Media reports over the past few days have suggested that the camera Schumacher was using to film his teenage son may have exacerbated the effects of the collision, with the theory being that a "shock effect" of the camera hitting the rock might have made it act as a hammer .

"The helmet completely broke, it was in at least two parts," a source close to the investigation is quoted as saying in several media reports.

"Ensa [the investigation body] received one piece of helmet to check the material and all was ok. But why did it explode on impact?

"Here the camera comes into question. The laboratory is testing to see if the camera weakened the structure."

[LINK: 'Nobody to blame' for crash that put Schumacher in coma]

Franck Leplanquais of sports equipment test lab CRITT explained how the camera could have been to blame in an interview with the Cologne Express.

"The camera is another element between rock and skull, and at the wrong angle could lead to a 'shock-effect', cracking the helmet."

Helmet manufacturer Uvex confirmed to the same paper that "a camera may affect the protective effect" of any helmet, depending on the circumstances of the crash.

Schumacher was woken from his artificially-induced coma earlier this month, and is reportedly able to respond to basic commands, though experts have warned that he faces a long and arduous recovery.