th and 19 th , 1999*
REMARKS FROM THE SCIENTIFIC ORGANIZERS
In 1995 we decided to organize a meeting on Computer Assisted Orthopaedic Surgery. When we sent out the announcements, we called it "First Symposium", without knowing whether we would be successful enough to ever have a second one. Well, we have now reached symposium number four, and since 1997 our North American "twin", CAOS/USA, has been held in Pittsburgh, Pennsylvania. This increase in popularity was one of the main reasons why we had to look for another location after CAOS III in Bern in November 1997. We found the ideal place at the Convention Center in Davos, Switzerland.
The first three symposia relied upon an invited faculty, but this year we were overwhelmed by the more than 70 abstracts that we received as a result of our call for papers. This also indicates the growing attention that is being paid to Computer Assisted Orthopaedic Surgery by the medical community.
Back in 1995, most lectures presented laboratory settings and CAOS systems under development. Besides ROBODOC, only a few pedicle screw systems had been used clinically up to that point. In this year's program, however, in vivo experience from almost all anatomical areas was represented. Many systems have become commercial products, helping to improve accuracy and to reduce surgical risk to patients. It also appears that the obvious success of CAOS technology gave the researchers time to think about related issues and side aspects -Session VIII reflects this trend.
We would like to thank the program committee for their assistance, and all sponsors that allowed us to set up CAOS this year. Special thanks go to all the participants, without whom the great success that the symposium has now achieved would not have been possible.