A South African teenager who was raped and murdered earlier this year was disembowelled with a blunt object, possibly by hand, leaving over a metre of her small intestines protruding from her vagina, a court has heard.

Anene Booysen's death in February caused widespread anger over violence against women in South Africa, with president Jacob Zuma calling the attack "shocking, cruel and most inhumane".

She was found at a construction site near her home in Bredasdorp in the Western Cape by a security guard. She had been raped and mutilated and died six hours later in hospital.

Initially two men were arrested for the attack but one, her ex-boyfriend Jonathan Davies, later had all charges against him dropped.

The other accused Johannes Kana admitted, in his trial at Swellendam Circuit Court, to leaving the pub with Booysen on the night of the attack. He hit her and raped her but denies murder. "I pulled down her pants ... kicked her ... and raped her," he said in a statement.

The doctors treating Booysen described her horrific injuries to the jury at the trial.

According to Eyewitness News, Dr Elizabeth De Kock, who was first to attend to Booysen when she was brought into hospital, said her injuries were the worst she had ever seen and that she could not have been saved due to the massive injuries sustained to her intestines.

She said she was covered from head to toe in sand and blood and had bruises all over her body. She said a sharp object had been used to mutilate her genitalia and that her intestines may have been pulled from her vagina by hand.

Kana reprimanded

De Kock added that she could not tell if the injuries had been cause by more than one person - it was initially believed Booysen had been gang raped before her death.

Pathologist Karisha Quarrie, who examined Booysen's body after her death, said the cause of death was her mutilated genital area: "All injuries were consistent with a blunt object such as a brick, baseball bat or stick," South Africa's Times Live newspaper reported.

She said there were signs of accelerated decomposition to her intestines and excessive damage to her anus wall, indicating a great deal of force was used: "The intestines appeared to have already died while she was alive.

"The large intestines, which are attached to the stomach wall, were still inside the body but 1.2m of the small intestines were outside the body through the vagina."

While presenting their evidence, Kana was reprimanded by the judge for showing little interest in the details of Booysen's injuries.

Swellendam Circuit Court interpreter Aubrey Jonase, who was translating the case into Afrikaans on Kana's behalf, said: "He is not even listening. What is the point if he is not listening?"

Speaking to the accused, Judge Goliath said: "Mr Kana, would you please show some enthusiasm and appreciation?"

So far 15 of the 52 witnesses have testified at the trial, which is expected to finish by the end of October. If found guilty, Kana faces life imprisonment.