Background: Metastatic disease of the acetabulum
can be painful and disabling. Operative intervention is indicated
for patients who fail to respond adequately to nonoperative treatment.
We evaluated the functional and oncological outcome of acetabular
reconstruction after curettage for the treatment of refractory symptomatic
Methods: Fifty-five patients with metastatic
disease of the acetabulum were treated with operative acetabular reconstruction
combined with a total hip replacement. The most common primary tumor
was carcinoma of the breast (eighteen patients), followed by carcinoma
of the kidney (seven patients) and carcinoma of the prostate (seven
patients). Forty (73 percent) of the patients presented with multiple
skeletal metastases, and eighteen (33 percent) had associated visceral
metastases. Twenty-eight (51 percent) had severe pain requiring
continuous use of narcotics, twenty-four (44 percent) had moderate
pain requiring periodic use of narcotics, and the remaining three
(5 percent) had mild pain requiring use of non-narcotic analgesics.
Eighteen (33 percent) of the patients could not walk, twenty-three
(42 percent) needed a walker or crutches, twelve (22 percent) used
a single cane, and two (4 percent) walked without assistive devices.
Intralesional curettage of the tumor was performed in all of the
patients. Fifty-four of the hips were reconstructed with a protrusio
cup and one, with a hemipelvis endoprosthesis. Large defects were reinforced
with cement and pin or screw fixation (the modified Harrington technique),
which allowed transmission of weight-bearing forces to the remaining
intact pelvis. Thirty-six acetabular reconstructions were performed
with antegrade pins or cannulated screws; fifteen, with long retrograde screws;
and four, with cement.
Results: The median period of survival was nine
months. Patients with visceral metastases had a median period of
survival of three months compared with twelve months for patients
without visceral metastases (p < 0.001). Patients with breast
cancer presented later in the disease process (p < 0.004) and
lived longer than did those with other carcinomas (p < 0.004).
Forty-five patients were evaluated three months after reconstruction.
Thirty-four (76 percent) of them had relief of pain as determined
by decreased use of narcotics. Nine of the eighteen patients who
could not walk preoperatively regained the ability to walk. Fourteen
of the seventeen patients who originally were able to walk in the
community retained that ability. Thirty-three patients were available
for evaluation at six months. Twenty-five (76 percent) still had
relief of pain, and nineteen (58 percent) were able to walk and
function in the community. Overall, fourteen (25 percent) of the
fifty-five patients had moderate local progression of the disease,
and five of these patients had failure of the fixation. Fourteen
early complications developed in twelve (22 percent) of the patients.
One patient (2 percent) died perioperatively.
Conclusions: Patients who have acetabular metastases
that are refractory to radiation and chemotherapy have a short life
expectancy. The early, gratifying results of reconstruction validate
the role of operative treatment as a short-term palliative procedure. Protrusio
acetabular cups presumably compensate for deficiencies of the medial
wall, while cement and pin fixation can be used effectively to reconstruct
large defects in the acetabular column and dome. The low rate of
fixation failure supports the biomechanical principles of the reconstruction. Generally,
the reconstructions are sufficiently durable to exceed the life
expectancy of the patients.