Application of Bench-Mounted Saws for Precision Replacement Arthroplasty of the Arthritic Knee — The Questor Systems

Prosthetic replacement arthroplasty has revolutionised surgical treatment for arthritis of hip and knee joints, but as time passes, the number of failures, (mainly) due to loosening of the implant, increases. Although poor design and material features have a recognised importance in loosening, a malpositioned prosthesis must carry the greatest responsibility [1–4]. The precision involved in the manufacturing process of the implant is set to a level of tolerance ±0. 2 mm. This is, in all likelihood, a factor of over ten times greater precision than current bone cutting/placement techniques. The geometric accuracy employed in the construction of the implants sets a standard to be emulated in the orientation and accurate placement of the prosthesis; it recommends a comparably high level of placemealignment accuracy for the bone cuts.