Background: The purpose of this study was to assess the rate of union, time
to union, and complications associated with the extended slide trochanteri
c osteotomy. We also evaluated how outcomes were influenced by the preopera
tive cortical-bone thickness, the preoperative cancellous-bone quality of t
he greater trochanter, the number of cables used to reattach the trochanter
ic osteotomy fragment, and the use of cortical strut augmentation.
Methods: We reviewed the results for forty-six hips in forty-five patients
who underwent a revision total hip arthroplasty with an extended slide troc
hanteric osteotomy between December 1991 and December 1996. Twenty-three pa
tients were men, and twenty-two were women; the mean age at the time of the
operation was 66.3 years. Two hips had an isolated acetabular revision, fi
fteen had an isolated femoral revision, and twenty-nine had acetabular and
femoral revisions. One patient (one hip) was lost to follow-up.
Results: At a mean of forty-four months after the operation, the rate of un
ion of the distal osteotomy site was 98 percent (forty-four of forty-five h
ips), with no change in the femoral component position. The time to union w
as not significantly correlated with the number of cables, the preoperative
cortical-bone thickness, or the preoperative cancellous-bone quality of th
e greater trochanter. Interestingly, the time to bridging-callus union was
significantly longer in the hips with a strut allograft than in the hips wi
thout a strut allograft (p = 0.04, t test for independent samples). Two fra
ctures of the osteotomy fragment occurred, but neither necessitated another
revision.
Conclusions: The extended slide trochanteric osteotomy allows extensive ace
tabular and femoral exposure, facilitates removal of distal cement or a wel
l fixed porous-coated stem, and allows reliable reattachment and healing of
the trochanteric fragment.