Cemented Constrained Liners Used as an Articulating Hip Spacer for the Treatment of Chronic Prosthetic Joint Infection.

Background: Two-stage exchange arthroplasty remains the gold standard for treating chronic hip periprosthetic joint infections. However, controversy remains regarding the optimal spacer type, particularly among patients with increased dislocation risk. This study reports on the outcomes of articulating hip spacers utilizing a single constrained-liner design.

Methods: All patients who underwent treatment for hip periprosthetic joint infection at a single institution were screened. Patients were included if they received an articulating spacer utilizing a constrained liner of a single manufacturer design. Indications for constrained liner, demographic variables, and surgical variables were recorded. Patients were assessed for dislocation and component loosening prior to the second stage or at the final follow-up if the second stage was not undertaken. Comparative analysis was performed.

Results: Overall, 26 constrained liners were utilized in 25 patients. Indications for constrained liner included history of dislocation (n = 14), massive proximal femoral bone loss (n = 14), greater trochanteric deficiency (n = 12), and absent abductors (n = 7). Many patients had more than one indication. In total, 9 hips (34.6%) underwent a second stage at an average of 7.4 months, while 17 hips never underwent a second stage with an average follow-up of 27.6 months. One patient experienced failure of their constrained liner prior to the second stage due to pelvic discontinuity and massive acetabular bone loss.

Conclusions: Utilization of a constrained liner as an articulating spacer is a viable option for patients at high risk of instability. Meticulous cement technique, appropriate component position, and implant selection are crucial in achieving successful outcomes.