Monday, January 11, 2010
Turning wood into bones
By Duncan Kennedy
BBC News, Rome
A novel - and natural - way of creating new bones for humans could be just a few years away.
Scientists in Italy have developed a way of turning rattan wood into bone that is almost identical to the human tissue.
At the Istec laboratory of bioceramics in Faenza near Bologna, a herd of sheep have already been implanted with the bones.
The process starts by cutting the long tubular rattan wood up into manageable pieces.
It is then snipped into even smaller chunks, ready for the complex chemical process to begin.
The pieces are put in a furnace and heated.
In simple terms, carbon and calcium are added.
The wood is then further heated under intense pressure in another oven-like machine and a phosphate solution is introduced.
After about 10 days, the rattan wood has been transformed into the bone-like material.
The team is lead by Dr Anna Tampieri.
An X-ray of the new bone fusing with the old
Within months, the real and artificial bone will have fused
"It's proving very promising," she says. "This new bone material is strong, so it can take heavy loads that bodies will put on it.
"It is also durable, so, unlike existing bone substitutes, it won't need replacing."
Several types of wood were tested before they found rattan works best.
That is because of its structure and porous properties, which enable blood, nerves and other compounds to travel through it.
Dr Tampieri says it is the closest scientists have ever come to replicating the human bone because, she says: "It eventually fuses with real bone, so in time, you don't even see the join."
The new wood bone is being closely studied at the nearby Bologna University hospital.
That is where orthopaedic surgeons like Maurillo Marcacci are monitoring the sheep tests.
The X-rays of the sheep's legs show the progress they are making.
Surgeon Mr Marcacci
A strong, durable, load-bearing bone is really the holy grail for surgeons like me and for patients
Particles from the sheep's own bones are migrating to the bone made from wood.
Within a few months, the real and the artificial bone will be like one continuous bone.
Mr Marcacci says that existing bone substitutes, like metal or ceramic, or bones from dead bodies, all have their drawbacks.
He says for people with major trauma accidents or cancer, the current range of alternatives can be weak and do not fuse with the existing bone.
The new wood bones, he says, could be a major step forward.
"A strong, durable, load-bearing bone is really the holy grail for surgeons like me and for patients," he says.
The new bone-from-wood programme is being funded by the European Union.
Implants into humans are about five years away.
But with no signs of rejection or infection in the sheep, there is real hope here that a natural, cheap and effective replacement for bones is now possible.
Bones from wood could soon be opening up a new branch of medical science.