Early Intraprosthetic Dislocation After Closed Reduction of Dual-Mobility Total Hip Arthroplasty: A Case Report.

Intraprosthetic dislocation (IPD) is a rare complication of dual-mobility (DM) total hip arthroplasty (THA), defined as dissociation of the polyethylene (PE) liner from the femoral head. While IPD has classically been linked to late-stage PE wear and long-term mechanical failure, recent studies and case reports have increasingly identified early, iatrogenic IPD as a potential complication following closed reduction of dislocated DM THA components. We report the case of a 75-year-old male who underwent THA with a DM acetabular component following a femoral neck fracture. Sixteen days after surgery, the first dislocation occurred and was managed with a bedside closed reduction performed without anesthesia or fluoroscopic guidance, which showed no immediate evidence of PE liner dissociation. Three days later, a second dislocation occurred. Radiographs revealed an eccentrically positioned femoral head, and computed tomography confirmed PE liner migration. Revision surgery identified the liner in the gluteus medius muscle. A new cemented DM component was implanted; the femoral stem was retained in place. This case highlights the importance of prevention of iatrogenic IPD through appropriate use of anesthesia and fluoroscopic control during closed reductions. Early recognition remains critical to avoid further complications. Gentle manipulation under fluoroscopic guidance is essential to prevent iatrogenic damage. Radiographic signs of eccentric head positioning or absence of the liner should prompt immediate evaluation.