The Journal of Bone and Joint Surgery, Vol 77, Issue 8 1217-1226, Copyright © 1995 by Journal of Bone and Joint Surgery, Inc
Revision total hip arthroplasty without cement: subsidence of proximally porous-coated femoral components
CL Peters, DP Rivero, LR Kull, JJ Jacobs, AG Rosenberg and JO Galante
Department of Orthopedic Surgery, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA.
We prospectively studied the intermediate-term results of forty-nine
revision total hip arthroplasties without cement that were performed
because of aseptic loosening of a cemented femoral component in forty-five
consecutive patients; the mean duration of follow-up was sixty-five months
(range, forty-five to eighty-seven months). A curved, long-stem,
titanium-alloy, non-circumferentially porous-coated femoral component was
implanted in each hip. Preoperatively, a staging system was used to
classify deficiencies of femoral bone stock according to the loss of
cancellous or cortical bone in the metaphysis and diaphysis. Forty-one hips
(84 per cent) had cortical or ectatic cavitary bone loss in the metaphysis.
The mean Harris hip score significantly improved from 54 points
preoperatively to 84 points at the time of the latest follow-up examination
(p < 0.001). Twenty-seven patients (twenty-eight hips; 57 per cent) had
at least two millimeters of subsidence of the femoral component during the
first postoperative year. Eight patients (eight hips; 16 per cent) had no
further progression of subsidence. Twenty-one patients (twenty-two hips; 45
per cent) had at least two millimeters of subsidence on two separate
postoperative evaluations and therefore were considered to have progressive
subsidence. Seventeen patients (nineteen hips; 39 per cent) had no
measurable subsidence and were considered to have a stable femoral
component. One of these seventeen patients had had a bilateral femoral
revision and had progressive subsidence on one side. There was a positive
trend for an association between subsidence and the degree of preoperative
femoral bone deficiency (p = 0.10), but there was no association between
subsidence and the fit of the prosthesis in the metaphysis and diaphysis or
the fill of the canal of the femur (p > 0.50). There was no significant
loss of bone in the hips with either a stable or a subsided femoral
component (p > 0.50), and qualitative reconstitution of the cortex was
noted in eleven (52 per cent) of the twenty-one most severely deficient
(stage-III) femora. Survivorship analysis showed that, at seventy-two
months, there was a 96 per cent chance of survival of the component (95 per
cent confidence limits, 0.89 to 1.0) with revision as the end point but
only a 37 per cent chance of survival (95 per cent confidence limits, 0.15
to 0.59) with revision or progressive subsidence as the end point.(ABSTRACT
TRUNCATED AT 400 WORDS)
CiteULike 
Connotea 
Del.icio.us 
Technorati What's this?
