Custom-made bones to be grown within hours

[loki]

The world's first custom-made bones that can be "grown" in a matter of hours and fit precisely into a break could be available within three years.


By Julian Ryall in Tokyo
Last Updated: 1:36PM GMT 25 Nov 2008

The new bones will replace damaged or ceramic versions that are currently used in reconstructive surgery.

They are made of one of the key materials in human bone, calcium phosphate, which means they will not be rejected by the body and will be completely absorbed into the skeleton within a couple of years.

Japanese researchers have made the breakthrough and say they will be available for use on the skull within three years and then the rest of the body soon after that.

Yuichi Tei, a professor of bioengineering at the University of Tokyo, said: "We have just completed the investigative study and clinical trials are under way on patients.

"Some people have congenital defects, others have lost bone after undergoing surgery for cancer, while others have been in traffic accidents.

"The reactions we have had so far have been very favourable."

Named CT Bone, the revolutionary system takes a series of minutely detailed pictures and x-rays to form a three-dimensional image of the affected portion of skull.

Once the 3-D image has been taken, layers of calcium phosphate just 0.1mm thick are laid on top of each other hundreds of times – in a similar way to an inkjet printer – until they match the exact shape and size of bone required.

The device, which was developed with Tokyo-based firm Next 21, repeats the process and builds up layers – 100 layers create a one-centimetre thick implant.

The technology also has narrow holes running through the artificial bones, inviting blood vessels and cells to come and help regenerate bone.

At present, the treatment is only available for head injuries because the material is not sufficiently strong to bear a heavy weight, ruling it out for a replacement shin or thigh bone at the moment, Dr. Tei said.

"Since the piece is based on computer tomography data, they are accurate to within 1mm," said Dr. Tei. "That is more accurate than the hands of a surgeon and sufficiently close for use in a replacement operation."

Studies have shown that the host bone serves as an incubator that provides cells to the artificial bone and can absorb a graft measuring 1cm within two or three years.

The clinical trials are scheduled to last two years and involve 70 adults at 10 hospitals. Dr. Tei's team has already used the technique on 10 patients and expect it to be ready for practical use in as little as three years.

As ceramic implants are brittle, surgeons often have to scrape the patient's host bone instead to help conventional implants fit better.

Doctors also often take bone from elsewhere in the body, particularly the hip, for conventional transplants.

Tsuyoshi Takato, an orthopaedic surgeon and professor at the University of Tokyo's Graduate School of Medicine, said: "Nearly half of it is often wasted in the process of making an implant that fits. It is very good to be able to reconstruct bone without taking a piece from elsewhere."

Takato hopes to use CT Bone for children if the clinical tests go well.

"Even if I want to treat their skeletal damage or development abnormality, I can't take bone from children for grafts. This technology should benefit children," he said.

http://www.telegraph.co.uk/health/35...hin-hours.html

[Knight of the Word]

They also have a new way of making a titanium rod that they can grow through magnetism, to fix breaks and replace certain bones, as the person grows they can also stretch the rod. Science is growing in leaps and bounds in this type of technology.