Longevity® constrained cup: an operative technical tip for prevention of metallic ring disassembly

Constrained liners are a salvage procedure for treating or preventing recurrent dislocations. The Longevity® constrained liner (Zimmer) has a special design with cut-outs on its circumference for avoiding impingement in certain areas and a metallic constraining ring that has to be impacted. The ring impaction may be technical demanding. We recommend preassembly with the head component prior to seating into the acetabular cup, thus avoiding the soft tissue or cement interference and malposition due to bad angle of incidence of impaction force.