The use of water-jetting technology in prostheses revision surgery?First results of parameter studies on bone and bone cement

Abstract

Water-jet cutting techniques have been used in industrial applications for many different materials. Recently these techniques have been developed into a revolutionary cutting tool for soft tissues in visceral surgery. The present study investigates the usage of this cutting technology for the revision surgery of endoprostheses. In the first part of the study, samples of bovine bone and acrylic bone cement (PMMA) were cut using an industrial jet cutting device with pure water. Below 400 bar, only PMMA was cut; above 400 bar, bone was also cut, but only pressures above 800 bar resulted in clinically useful rates of material removal (cut depth 2. 4 mm at 10 mm/min traverse speed). In the second part of the study, the effect of adding biocompatible abrasives to the water in order to reduce the required pressure was investigated, resulting in a significantly higher removal of material. At 600 bar, PMMA was cut 5. 2 mm deep with plain water and 15.2 mm deep with added abrasives. The quality of the cuts was increased by the abrasive. Though there was no clear selectivity between bone and PMMA any more, the rate of material removal at similar pressures was significantly higher for PMMA than for bone (600 bar: 1.6 mm cut depth for bone samples, 15.2 mm for PMMA). The measured cut depths with either method were not influenced by a change of the cutting direction with respect to the main direction of the osteons in the bone. However, a reduction of the jet surface angle (90 degrees to 23 degrees ) resulted for bone in a significantly lower cut depth at 600 bar (plain water: 0.62 mm vs. 0.06 mm; abrasive: 1.61 mm vs. 0.60 mm). The laboratory experiments indicate that abrasive water jets may be suitable for cutting biomaterials like bone and bone cement.

Waterjet cutting of periprosthetic interface tissue in loosened hip prostheses: An in vitro feasibility study

“…5) and this might have influenced the statistical analysis. However, an increasing required waterjet pressure with increasing tissue sample thickness seems to be logical as larger cutting depths in bone or bone cement require higher waterjet pressures [19,20].…”

“…The waterjet was aligned with the centerline of the slot to assure the waterjet came only in contact with the tissue. The stand-off distance of the nozzle tip to the interface tissue surface was set to 5 mm [2,20] and the waterjet was aimed perpendicular to the specimen surface [2,19,20,23]. A linear stage was used to move the sample with a constant traverse speed (0.5 mm/s) to simulate the cutting process in a reversed way.…”

“…Soft tissues, e.g. liver tissue, can be cut at low waterjet pressures (<5 MPa) [2], while bone can be cut at much higher waterjet pressure (around 40 MPa) [16,19,20]. Secondly, no heat is generated during the cutting process, which is important to avoid thermal damage to tissue in the proximity of the working area [21].…”

“…Secondly, no heat is generated during the cutting process, which is important to avoid thermal damage to tissue in the proximity of the working area [21]. Thirdly, tissue can be cut within small spaces with very low reaction forces (<5 N) [19]. Fourthly, the cut is always sharp and clean which has led to further exploration of waterjet technology for application in orthopedic surgery [19,20,22,23].…”

“…Thirdly, tissue can be cut within small spaces with very low reaction forces (<5 N) [19]. Fourthly, the cut is always sharp and clean which has led to further exploration of waterjet technology for application in orthopedic surgery [19,20,22,23]. Finally, water can be supplied via flexible tubing, which offers possibilities for minimally invasive surgical access.…”