South Africa's world champion Caster Semenya pulls out of Commonwealth Games with a back injury

Caster Semenya, the women's 800m world champion, has withdrawn from the Commonwealth Games because of a back injury dealing the event another blow.

The 19-year-old, cleared to compete again in July after controversial gender tests had put her career on hold since she won the world title in August 2009, has suffered serious lower back pain and been uncomfortable in her last few races.

Semenya had an MRI scan earlier on Tuesday which showed an inflammation of the spine and left the South African Sports Confederation and Olympic Committee (Sascoc) with no alternative but to pull the medal prospect out of their team.

'It would serve no purpose to have an athlete in Delhi who was struggling with any sort of injury that would compromise performance and it is our medical view that physically and emotionally she would not be capable of doing justice to her talent at an event of this magnitude,' Shuaib Manjra, Team South Africa's chief medical officer said in a statement.

Sascoc chief executive Tubby Reddy said Semenya's withdrawal was a blow to South Africa's medal hopes at the games but the welfare of the athlete was his organisation's main concern.

'She was one of our athletes that was expected to do well and win a medal,' Reddy said. 'But if she is carrying an injury it would do her no good to try and compete in Delhi because it could impact on her future achievements. We have thus decided to follow our medical team's advice and withdraw her from the team.'

Other high-profile athletes missing from the Games include world champion sprinter Usain Bolt, who said the event had come too late in the year, and Kenyan 800m world record holder David Rudisha, who blamed tiredness for his withdrawal.

The absence of some of the world's top athletes has taken a lot of the shine off an event India had hoped to use to display its growing global influence, rivalling China which put on a spectacular Olympic Games in Beijing two years ago.

Other athletes have pulled out citing health concerns surrounding dirty accommodation in the athletes' village while some have withdrawn becuase of fears over security.