By Pritha Sarkar

RIO DE JANEIRO (Reuters) - Germany's Fabian Hambuechen demanded an overhaul in the gymnastics scoring system on Saturday after team mate Andreas Toba and Frenchman Samir Ait Said provided painful reminders of just how dangerous the sport can be.

Ait Said ended up in hospital with a broken leg that was left dangling from below his knee following a crash landing from the vault.

He was wheeled out of the arena on a stretcher shortly after Toba cried out in agony following a fall from a tumbling run on the floor exercise which is suspected to have ruptured his ACL.

Toba went on to perform on the pommel horse but as he limped off that apparatus with his arms around his team mates, it was clear that his Games were over.

As far as 2007 horizontal bar world champion Hambuechen was concerned, the accumulative scoring system that replaced the old 10.0 format following a judging scandal at the 2004 Athens Olympics is to blame for the injuries.

"It's a pity that gymnastics has developed the way it has. Everyone is chasing more and more difficulty, more risk. Everyone wants new records so it's getting dangerous," said Hambuechen, one of the few gymnasts in Rio who also competed under the old system.

"That's really annoying. I don't like this system in gymnastics. I hope they will change it after Rio."

The system is made up of two different scores. The D (difficulty) score involves adding up the hardest and specific requirements in a routine, while all gymnasts begin with a 10.0 E (execution) score from which points are deducted for flaws such as bent legs, botched landings and falls. The two scores are then added together for a final score.

It is the pursuit of earning a high D-score that makes gymnasts push the boundaries, often with dire consequences as witnessed on Saturday.

Four years after hurting his right leg at the 2012 London Games, Ait Said was again in agony when a misjudged vault landing left him clutching the back of his left knee as he lay prostrate on the crash mat.

It soon became apparent that he would take no further part in the Rio Games after suffering what his team mates called "a catastrophic injury".

After a delay of several minutes, he was wheeled out on a stretcher and raised one arm to acknowledge the loud ovation he received from the crowd.

"He is in the hospital with a doctor now. We don't know what happened, except that it was his tibia. We will do more exams to see if it is just the bone," said France team leader Corrine Moustard-Callon.

The governing body of gymnastics (FIG) declined to comment when contacted by Reuters.

(Editing by Ed Osmond)