Assessment of risk factors for occurrence or worsening of acetabular fracture following percutaneous cementoplasty of acetabulum malignancies

Purpose To evaluate the clinical, radiological and periprocedural features associated with the occurrence or worsening of acetabular fracture (OWAF) following percutaneous cementoplasty of the acetabulum (PCA) in cancer patients. Method All patients who underwent PCA in our comprehensive cancer center for an acetabular metastasis between January 2008 and December 2015 were included. Clinical features, characteristics of the metastasis on computed tomography (CT-scan) (location [roof, quadrilateral surface, anterior and posterior columns], number of locations, matrix, extra/intra-articular fractures, extra-osseous or subchondral extensions) and of the procedure (extra- or intra-articular cement leakage (IACL), percentage of filling of each location, complications) were reported as well as prior, concomitant or post-PCA treatments. The endpoint was OWAF on CT-scan during post-PCA follow-up. Log-rank tests and Cox models were used to identify prognostic factors. Results 140 PCA were identified in 129 patients (11 bilateral procedures, median age: 66.6). Eighteen (18/140, 12.9%) had an initial articular fracture. IACL was seen in 12/140 (8.6%) PCA. The only feature associated with IACL was a pre-existing articular fracture (p = 0.009). Of the 111 patients with imaging follow-ups, 18 (16.2%) showed OWAF. In multivariate analysis, the presence of cement filling (even partial) of all acetabular metastatic locations was the only feature predictive of OWAF-free survival (hazard ratio = 3.8, p = 0.031). Conclusions Injecting cement in all areas affected by acetabular metastases could prevent OWAF. Because survival following PCA is not negligible, completing an insufficient first PCA could help preserve patients' quality of life.