This paper suggests that bone-cement interlocking is superior when the cut surfaces of the bone have been prepared using pulsed lavage with saline prior to application of cement and the prostheses during total knee joint arthroplasty.

The aim is to put the case forward for the inclusion of the question whether or not pulsed lavage was used on the National Joint Register questionnaire. This will then in course give guidance as to whether there is an improved outcome when pulsed lavage was used or whether it is a waste of resources.

Review of the 6-month postoperative films of the total knee joint replacements of two senior surgeons was carried out in 1996. Both surgeons use the Genesis total knee system. Surgeon 1 uses pulsed lavage routinely, and surgeon 2 does not. This is the only difference in their techniques. There have been no early aseptic failures in either group at 5 years. A lucent line was consistently seen between the bone-cement interface when pulsed lavage was used. Furthermore, the depth of the cement mantle on the tibia was greater in the pulsed lavage group. We suggest that the use of pulsed lavage at the preparation of the cut bone surfaces before the application of the cement and prostheses improves the bone-cement interface. The significance of this finding is uncertain, but a case can be made for this question to be included in the National Joint Register questionnaire.