Is an Acetabular Cage and Cement Fixation Sufficiently Durable for the Treatment of Destructive Acetabular Metastases?

Abstract

Background Destructive bony acetabular metastases cause pain, pathological fractures, and loss of mobility. Although multiple fixation options are available, we have favored a rigid stainless steel partial pelvic cage for acetabular fixation in these patients; however, little is known about the durability of this approach. Question/purposes (1) How common was loss of fixation in a small series of metastatic acetabular defects treated with an acetabular cage and cemented total hip replacement? (2) What is the implant survival free from reoperation or revision at 2 and 4 years using a competing-risks survivorship estimator in patients thus treated? (3) What complications were associated with the treatment? (4) What level of postoperative mobility was achieved? Methods Between 2006 and 2017, we treated all acetabular metastases that needed surgical intervention, not amenable to conventional cemented THA alone with our single technique of acetabular partial pelvic cage and cemented total hip replacement. We treated 47 hips in 46 patients whose acetabular metastasis led to acetabular collapse or who were unresponsive to nonoperative measures of radiation therapy and analgesia. Routine followup occurred at 3 and 12 months; 17 of 46 patients (37%) died before 1 year, and all other patients were followed beyond 1 year. Only one patient who remains alive has not been seen in the past 5 years. Loss of fixation was determined by radiological or clinical signs of cage loosening. Survivorship free from reoperation or revision at 2 and 4 years was determined using competing-risks analysis. We did not assess patient-reported outcomes, but we did have data on the proportion of patients who were able to ambulate in the community and if so, what assistive devices they used, which we obtained by chart review. Results One patient experienced cage loosening identified 8 years postoperatively as a result of local disease progression and has been managed with observation. No patients underwent revision for loss of acetabular fixation. The cumulative incidence of reoperation or revision was 8% at 2 years (95% CI, 3.6–12.6) and 16% at 4 years (95% CI, 9.2–23.2). Four patients had postoperative dislocations, of which three underwent reoperation. One patient developed a postoperative deep infection and underwent reoperation. One patient died within 30 days of surgery. Only one patient did not ambulate in the community postoperatively; 23 ambulated independently, 10 with the use of a walking stick and 12 using a walker. Conclusions In this small series, we found this approach sufficiently durable to continue its use for patients with acetabular metastases with collapse or those not responding to nonoperative measures. However, comparison studies are needed to determine whether it is superior or inferior to other available alternatives. Level of Evidence Level IV, therapeutic study.

Modified Harrington’s procedure for periacetabular metastases in 89 cases: a reliable method for cancer patients with good functional outcome, especially with long expected survival

“…The OHS is a validated, reliable, and well-established PROM for evaluating the outcomes of THA (Dawson et al 1996). It is difficult to compare our results with the literature, as postoperative mobility has been reported in different ways (Harrington 1981, Marco et al 2000, Shahid et al 2014, Charles et al 2017, Wegrzyn et al 2018, Rowell et al 2019. Based on Marchetti's grading system (Marchetti et al 2005), the functional outcome results were fair in our population when all patients were evaluated together (HHS score 76 out of 100).…”

A modified Harrington technique for periacetabular reconstruction in advanced metastatic bone disease and a discussion of alternative treatment options

“… 10 Since then, periacetabular reconstruction has advanced to intralesional curettage followed by saddle prostheses, allograft or allograft prosthetic composites, pasteurized autografts, porous implants, or custom-made prosthetic components. 11-16 Small to medium-sized case series have described the outcomes of periacetabular reconstruction using a combination of these techniques. Additionally, more recent constructs such as trabecular metal augments and three-dimensional [ e.g.…”

CORR Insights®: Is an Acetabular Cage and Cement Fixation Sufficiently Durable for the Treatment of Destructive Acetabular Metastases?

“…Fortunately, most acetabular metastases that are severe enough to warrant surgery can be managed with total hip replacement or an even less-invasive alternative such as percutaneous acetabuloplasty [3]. Only relatively rarely are pelvic metastases so symptomatic and severe that straightforward approaches fall short, as was highlighted in the current study by Rowell and colleagues [9]. The authors accumulated only 47 patients undergoing major structural acetabular reconstructions over a 12year period while working in the only tertiary musculoskeletal oncology practice in a 600-mile radius.…”

“…It is difficult to find a comparison to these findings. As the authors readily admit, their study was "small" [9]. Statistically, this is true; but practically, this is a reasonably sized series given the infrequency of patients requiring such treatment.…”

“…Nonetheless, there are limited conclusions that can be drawn from this work, and the comparison studies available for alternate techniques are generally as small or smaller, often historic relative to the rapidly involving treatments for metastatic disease, and roughly equivalent or even less homogeneous with regard to diagnoses, indications, and surgical techniques employed [5,6]. Currently then, the technique proposed by Rowell and colleagues [9] appears to be as good or better than other alternatives for the acetabular reconstruction in this patient population, given the caveat that our ability to do a robust comparison with alternate techniques is limited.…”