Two-stage strategy in end-stage hip periprosthetic joint infection: utility of industrially prefabricated custom-made antibiotic spacers

Purpose: Use of prefabricated mobile spacers in end-stage cases of hip periprosthetic joint infection (HPJI) is hindered when large bone defects exist. In such cases, prefabricated custom-made antibiotic spacers (P-CMAS) offer an alternative. Such spacers are individually designed according to the size and anatomical characteristics of the bone defect. The purpose of this study is to describe and evaluate the use of such patient-specific spacers in a two-stage strategy to treat end-stage HPJI cases, and to report on clinical outcomes. Methods: A retrospective study identified all patients with end-stage HPJIs from January 2015 through December 2019, treated using a P-CMAS. Primary outcome: infection eradication rate. Secondary outcomes: spacer-related complications and patient satisfaction. Minimum follow-up: 12 months after the second-stage surgery. Results: A total of 7 end-stage cases (mean of 6.7 previous surgical procedures) were included. Mean bone defect size was 191.57 (range 47-304) mm. Polymicrobial infection was detected in 42.86% of these cases. During the spacer stage there were no periprosthetic fractures, spacer dislocations or breakages, nor spacer-drug-related complications. All patients proceeded with the second stage uneventfully, with an average time between stages of 178 (range 119-326) days. In 5 cases a total femur arthroplasty was the reconstructive procedure performed. After a mean follow-up of 27.29 (range 14-49) months the infection was clinically eradicated in all patients, despite their difficult-to-treat scenarios. Conclusions: Industrially custom-made spacers offer an effective and safe option in performing 2-stage exchange arthroplasty in cases of end-stage HPJI with extensive bone defects.