Stemcells coaxed to rebuild bone, cartilage

Scientists have shown for the first time that it may be possible to replace a human hip or knee with a joint grown naturally inside the body using the patient's stem cells.

In experiments on rabbits, the researchers coaxed the animals' stem cells to rebuild the bone and cartilage of a missing leg joint, according to a study published Thursday.

"This is the first time an entire joint surface was regenerated with return of functions including weight bearing and locomotion," lead researcher Jeremy Mao, a professor at Columbia University Medical Center, said in a statement.

Naturally-grown joints would likely last longer than the current generation of artificial mechanisms, he said.

With ageing populations and many people under 65 requiring replacement surgery, there is a real danger patients will outlive metallic joints and require a second gruelling operation late in life.

In the experiments, Mao and colleagues removed the forelimb thigh joint of 10 rabbits, and then implanted a kind of scaffolding made of biologically compatible materials.

A naturally-occurring substance that stimulates cell growth then cued the rabbits' stemcells to go to the site of the missing joint and regenerate both cartilage and bone in two distinct layers.

Within four weeks, the animals resumed normal movements - a medical first, the researchers reported in the British medical journal The Lancet.

The fact that the regenerated limb joint was created from the stem cells in the host animal - rather than being harvested and then cultivated outside the body - is also unprecedented, they said.

This new procedure "may ultimately lead to clinical applications," said Mao. "In patients who need the knee, shoulder, hip or finger joints regenerated, the rabbit model provides a proof of principle."

But a number of scientific and regulatory issues remain before the procedure can be tested on humans, he said.

For hip replacements, for example, recovery in people will be more difficult because humans are carry all their weight on two legs.

Many patients are also likely to have existing conditions and drug regimens that could adversely affect the growth of new joints.

Some patients - especially elderly people with diabetes - will not have the same capacity for natural regeneration, cautioned Patrick Warnke of Australia's Bond University in a commentary, also in The Lancet.

The period of immobility while a joint regenerates also presents its own risks.

"The optimum way to grow a biological joint remains a controversy," Warnke said.

But, he added, the new research "offers a promising insight into what might be on the horizon."

As populations age in rich nations, the demand for total joint replacements has skyrocketed.

In the United States, more than 200,000 patients received total hip replacements in 2006, and nearly half a million got new knee joints, according to the US Nationwide Inpatient Sample database of hospital inpatient stays.

If these trends continue, an estimated 600,000 hip replacements and 1.4 million knee replacements will be carried out in 2015.

The United States accounts for 50 percent total procedures worldwide, with Europe accounting for 30 percent, according to Datamonitor.

An ageing population and increased incidence of obesity are primary causes for the increase in joint replacements.

mh/tw

 

Life and Style
ebookNow available in paperback
ebooks
ebookA delicious collection of 50 meaty main courses
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
SPONSORED FEATURES

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    Recruitment Genius: Sales Executive or Senior Sales Executive - B2B Exhibitions

    £18000 - £30000 per annum: Recruitment Genius: A Sales Executive or Senior Sal...

    Recruitment Genius: Head of Support Services

    £40000 - £55000 per annum: Recruitment Genius: This is an exciting opportunity...

    Recruitment Genius: Warehouse Team Leader

    £22000 per annum: Recruitment Genius: This industry leading company produces h...

    Recruitment Genius: Business Development Manager / Sales - OTE £40,000

    £20000 - £40000 per annum: Recruitment Genius: This IT provider for the educat...

    Day In a Page

    A nap a day could save your life - and here's why

    A nap a day could save your life

    A midday nap is 'associated with reduced blood pressure'
    If men are so obsessed by sex, why do they clam up when confronted with the grisly realities?

    If men are so obsessed by sex...

    ...why do they clam up when confronted with the grisly realities?
    The comedy titans of Avalon on their attempt to save BBC3

    Jon Thoday and Richard Allen-Turner

    The comedy titans of Avalon on their attempt to save BBC3
    The bathing machine is back... but with a difference

    Rolling in the deep

    The bathing machine is back but with a difference
    Part-privatised tests, new age limits, driverless cars: Tories plot motoring revolution

    Conservatives plot a motoring revolution

    Draft report reveals biggest reform to regulations since driving test introduced in 1935
    The Silk Roads that trace civilisation: Long before the West rose to power, Asian pathways were connecting peoples and places

    The Silk Roads that trace civilisation

    Long before the West rose to power, Asian pathways were connecting peoples and places
    House of Lords: Outcry as donors, fixers and MPs caught up in expenses scandal are ennobled

    The honours that shame Britain

    Outcry as donors, fixers and MPs caught up in expenses scandal are ennobled
    When it comes to street harassment, we need to talk about race

    'When it comes to street harassment, we need to talk about race'

    Why are black men living the stereotypes and why are we letting them get away with it?
    International Tap Festival: Forget Fred Astaire and Ginger Rogers - this dancing is improvised, spontaneous and rhythmic

    International Tap Festival comes to the UK

    Forget Fred Astaire and Ginger Rogers - this dancing is improvised, spontaneous and rhythmic
    War with Isis: Is Turkey's buffer zone in Syria a matter of self-defence – or just anti-Kurd?

    Turkey's buffer zone in Syria: self-defence – or just anti-Kurd?

    Ankara accused of exacerbating racial division by allowing Turkmen minority to cross the border
    Doris Lessing: Acclaimed novelist was kept under MI5 observation for 18 years, newly released papers show

    'A subversive brothel keeper and Communist'

    Acclaimed novelist Doris Lessing was kept under MI5 observation for 18 years, newly released papers show
    Big Blue Live: BBC's Springwatch offshoot swaps back gardens for California's Monterey Bay

    BBC heads to the Californian coast

    The Big Blue Live crew is preparing for the first of three episodes on Sunday night, filming from boats, planes and an aquarium studio
    Austin Bidwell: The Victorian fraudster who shook the Bank of England with the most daring forgery the world had known

    Victorian fraudster who shook the Bank of England

    Conman Austin Bidwell. was a heartless cad who carried out the most daring forgery the world had known
    Car hacking scandal: Security designed to stop thieves hot-wiring almost every modern motor has been cracked

    Car hacking scandal

    Security designed to stop thieves hot-wiring almost every modern motor has been cracked
    10 best placemats

    Take your seat: 10 best placemats

    Protect your table and dine in style with a bold new accessory