Robot reduces spinal surgery risk

The robot can perform very precise surgery

Scientists are developing a robot that can reduce the risks associated with extremely delicate surgery on the spine.

The robot is capable of operating to the nearest tenth of a millimetre.

Operations on the spinal column are particularly delicate - one false movement of the scalpel can lead to paralysis.

However, surgery is often the only way to relieve patients of pain after a slipped disc, tumour removal or damage to vertebrae.

To reduce the risks involved, researchers at the four Fraunhofer Institutes in Germany are developing a surgical robot.

The robot's movements are steadier than the hand of the surgeon and more precise.

It is capable of inserting screws into the vertebrae to an accuracy of a tenth of a millimetre.

These screws are then used to attach rigid bars to the vertebrae in order to stabilise the spinal column.

To avoid injury, and ensure that the screws are inserted as precisely as possible, doctors have been using X-ray images to monitor such operations.

The disadvantage of this method is that X-ray pictures can only be taken at intervals of several minutes.

Frequent injury

The robot can insert screws into the vertebrae

As a result, despite taking the utmost care, there are frequent cases of injury to the bone marrow, adjacent nerves or major blood vessels.

Dr Peter Weber, of the Fraunhofer Institute for Biomedical Engineering (IBMT), said: "Until now, there was no way to monitor the insertion of the screws in real time."

Researchers have tackled the problem by linking the robot to a navigation system using ultrasound.

This allows the robot to monitor the insertion of the screws by taking ultrasound measurements.

Simultaneously, all relevant information is displayed to the surgeon on a console, allowing him or her to intervene in the operation at any time.

The surgical robot will go through its paces on dummy patients, before being employed for real-life operations on the lumbar region.

Dr Weber hopes that the robots will be capable of performing operations on the cervical vertebrae in the neck - some of which are currently impossible.

He said: "The vertebral structures are particularly fine here, and the risk of injury correspondingly high. The robot system could be a great help in this very sensitive region."

Dr Patrick Kluger, a spinal injury expert who works at Stoke Mandeville Hospital, said the robot was one of several techniques currently being developed.

These included the use of infra-red and magnetism as well as ultrasound. In fact, Dr Kluger has successfully carried out experimental surgery on the neck vertebrae using infra-red guidance.

However, Dr Kluger said it was now possible to carry out a wide range of interventions using modern surgical techniques without the need for robots.

He said: "Surgery on the vertebral column is still especially demanding and risky, and needs special experience and training.

"But at the moment there is still no evidence at all that the use of computer navigation and robots increases the capacity, ability or security of surgery."