Life means life: Cregan, Dennehy and Adebolajo will die behind bars, alongside some of the most notorious criminals in British history

There are now 51 prisoners currently serving whole-life sentences in the UK

Michael Adebolajo and Joanna Dennehy have been given sentences for life (AP;PA)

This week, the number of prisoners serving whole-life sentences in the UK rose to 51, as killers Michael Adebolajo and Joanna Dennehy were told they too would die behind bars.

Dennehy, 31, showed no emotion as she was sentenced on Friday for the murders of three men, and attempting to kill two others, in a 10-day killing spree last March.

Adebolajo, 29, one of two terrorists who murdered British soldier Lee Rigby in broad daylight in Woolwich last May, had to be dragged screaming from the dock as he was told he would serve a whole-life term on Wednesday.

They join the likes of Moors Murderer Ian Brady, who tortured and murdered children along with his accomplice, Myra Hindley; former nightclub bouncer Levi Bellfield, who was told he would "die in prison" for murdering two young women, trying to murder a third, and who was later convicted of the murder of schoolgirl Milly Dowler; and Steve Wright, who earned a whole-life term for the murder of five prostitutes in Ipswich.

Dennehy also joins the only other woman on the list, Rose West, who was convicted in 1995 for her role in the murder of 10 young women in with her husband Fred - who killed himself in prison before trial.

The court of appeal ruled on 18 February that the use of whole-life sentences could be used for the "most heinous crimes", contrary to the finding of the European Court of Justice, which had ruled that life "can never mean life" because it is a breach of human rights.

The sentences of murderers Jeremy Bamber, Douglas Vinter and Peter Moore amounted to "inhuman and degrading treatment", the Strasbourg-based Court of Human Rights had said, and called for whole-lifers to be entitled to a review of their sentence 25 years into their term at the latest.

But the court of appeal's panel of five judges made its decision in the face of the European court - and increased the 40-year minimum prison term being served by killer Ian McLoughlin, who stabbed a Good Samaritan to death while on day release from a murder sentence, to a whole-life tariff.

Before Dennehy and Adebolajo, the most recent prisoner to be handed a whole-life sentence had been Dale Cregan, jailed last year for the murder of four people - including police officers Nicola Hughes and Fiona Bone.

In 2013, child-killer Mark Bridger was also given a whole-life sentence for the murder of five-year-old April Jones, who was snatched outside of her home in Machynlleth, Powys, mid-Wales.

According to Ministry of Justice figures, the convictions of Bridger and Cregan last year took the number of prisoners for whom life really does mean life to 49. With the addition of Adebolajo and Dennehy, there are now 51 prisoners whose crimes are regarded as so shocking and so inhumane that they will never be set free.

All but five of those criminals are in prisons rather than hospitals - among them murderer and robber Donald Neilson, dubbed 'The Black Panther', who shot and killed three sub-postmasters; serial killer Peter Tobin, who is serving three life sentences for the murders of Vicky Hamilton, Angelika Kluk and Dinah McNicol; and Stephen Farrow, who was convicted in 2012 of murdering Rev John Suddards and pensioner Betty Yates.

Soham murderer Ian Huntley, who murdered Holly Wells and Jessica Chapman, both 10, in 2003, is not on the whole-life tariff list - but is serving a 40-year minimum term.

Stuart Hazell, who in 2013 admitted killing schoolgirl Tia Sharp and hiding her body in the loft of the home he shared with her grandmother, was given a 38-year minimum term.

For them, life may not mean life, but it will be a long time until they taste freedom.