C. Silverton et al., THE PROSTHESIS-BONE INTERFACE ADJACENT TO TIBIAL COMPONENTS INSERTED WITHOUT CEMENT - CLINICAL AND RADIOGRAPHIC FOLLOW-UP AT 9 TO 12 YEARS, Journal of bone and joint surgery. American volume, 78A(3), 1996, pp. 340-347
We evaluated the radiographic and functional status of a one-piece com
posite tibial component, designed to be inserted without cement, that
was developed and used only at our institution, Thirty-six patients (t
hirty-seven knees) were managed with the component between November 19
81 and September 1983, and none were lost to follow-up, When they were
last seen, thirty-four (92 per cent) of the thirty-seven knees had a
well fixed tibial component, both clinically and radiographically: Eig
ht patients (eight knees; 22 per cent) died, Eleven patients (eleven k
nees; 30 per cent) had a revision at an average of sixty-five months (
range, four to ninety-five months) postoperatively The reason for the
revision was failure of a metal-backed patellar component in three kne
es, excessive wear of the polyethylene of the tibial component in one,
a hematogenous infection in four, aseptic loosening of the tibial com
ponent in two, and chronic synovitis in one, The remaining seventeen p
atients (eighteen knees; 49 per cent) were seen for clinical and radio
graphic followup at an average of eleven years (range, nine to twelve
veers) after the operation, With removal of the implant as the end poi
nt, the cumulative rate of survival was 85 per cent at fifty-six month
s and 67 per cent at 108 months, Some of the failures, were secondary
to features of the prosthetic design that currently are considered to
be inadequate, including a metal-hacked patellar component and carbon-
fiber-reinforced polyethylene. In the twenty-six knees in which the p
rosthesis had been retained, the implant was stable and the prosthesis
-bone interface mas unchanged as seen radiographically at the time of
the most recent follow-up examination, This finding demonstrates that
a porous ingrowth surface is capable of providing a secure interface f
or biological fixation over the long term.