Background: Hemiarthroplasty is frequently used to treat femoral
neck insufficiency resulting from neoplastic disease in the proximal part of
the femur. The authors of a recent study analyzed the dislocation rates
following hemiarthroplasty but excluded patients with tumor involvement of the
site of the surgery as they hypothesized that the dislocation rates would be
markedly higher in such patients. The current study was performed to compare
the dislocation rate following hemiarthroplasties performed in patients
without tumor involvement with the rate following hemiarthroplasties in
patients with tumor involvement of the surgical site.
Methods: Patients who had undergone hemiarthroplasty following
resection of a tumor involving the proximal part of the femur were identified
in a total joint registry, and the patients' charts were reviewed
retrospectively to determine dislocation rates, preoperative conditions, and
postoperative outcomes and treatments. Between 1974 and 2001, 1812 patients
were treated with hemiarthroplasty for reasons other than tumor involvement
and 320 hemiarthroplasties were performed because of tumor-related conditions.
The patients who were treated for a tumor-related condition were younger, and
a higher proportion of them were men.
Results: The ten-year dislocation rate after the hemiarthroplasties
performed for tumor-related conditions (10.9%) was higher than that following
the hemiarthroplasties performed for non-tumor-related conditions (2.1%) (p =
0.002). The median time to dislocation in the patients with a tumor-related
condition (twenty-four days) was shorter than that for the patients without
tumor involvement (thirty-seven days). Preservation of the greater trochanter
in patients with tumor involvement did not have a significant influence on the
dislocation rate, but it showed a favorable trend toward decreasing that rate
(hazard ratio = 3.5, p = 0.06).
Conclusions: The short-term and long-term dislocation rates
associated with hemiarthroplasties performed for a tumor-related condition at
the site of the surgery were significantly higher than those associated with
hemiarthroplasties performed for reasons other than tumor involvement.
Preservation of the greater trochanter showed a trend toward decreasing the
likelihood of dislocation following the hemiarthroplasty, and it was more
influential than the level of resection and the extent of soft-tissue
compromise. We think that preservation of the greater trochanter should be
attempted when it is justifiable according to the principles of oncologic
Level of Evidence: Prognostic Level II. See Instructions
to Authors for a complete description of levels of evidence.