Component impingement in total hip arthroplasty (THA) can cause implant damage or dislocation. Dual mobility (DM) implants are thought to reduce dislocation risk, but impingement on metal acetabular bearings may cause femoral component notching. We studied the prevalence of (and risk factors for) femoral notching with DM across two institutions. We identified 37 patients with minimum 1-year radiographic follow-up after primary (19), revision (16), or conversion (2) THA with 3 distinct DM devices between 2012 and 2017. Indications for DM included osteonecrosis, femoral neck fracture, concomitant spinal or neurologic pathology, revision or conversion surgery, and history of prosthetic hip dislocation. Most recent radiographs were reviewed and assessed for notching. Acetabular anteversion and abduction were calculated as per Widmer (2004). Records were reviewed for dislocations and reoperations.INTRODUCTION
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