Jet water breaks legs in theatre

Surgeons could soon be wielding high-speed water jet devices instead of saws for cutting through bones if work being carried out by Durham University researchers is successful.

Speaking at the Institute of Physics annual congress this week in Telford, David Gregory-Smith of Durham University said that high-speed water jets have recently been used in operations involving the cutting of soft tissue such as liver and kidney.

But his team in the school of engineering, in collaboration with Julian Minns of Durham's Dryburn hospital, are hoping to extend the method to cover the cutting of bones. Dr Gregory-Smith said that cutting bones with saws or drills can cause excessive bleeding and the heat generated by friction can kill surface cells. Similar problems are also experienced when lasers are used, with the further difficulty of controlling the cutting depth and the possible biological hazard of vapourising diseased material.

The researchers have recently used commercially available water jets to cut through cow bones. The jets typically have nozzle diameters ranging from 0.25mm to 0.9mm and operate at pressures of about 130 bar. The cow bones were cut both at the joints and mid-shaft. The results so far are encouraging with a flatter cut being achieved than would be possible with a saw.

Dr Gregory-Smith says such a surface is particularly helpful in implant operations such as for hips and knee joints. The researchers are hoping to begin experimenting soon with artificial bones that have similar properties to human bones.