Dual mobility in primary total hip arthroplasty: A temptation from the devil or a blessing from above
Authors: Klumpp Raymond , Boerci Linda , Buonanotte Francesco , Zeppieri Marco 
Published: June 2024

Dual mobility (DM) bearings have gained significant attention in the field of total hip arthroplasty (THA) as a valid treatment option in cases of revision for instability after THA whereas its use in primary THA is still a matter of debate. This manuscript explores the pathology, incidence, diagnosis, treatment options, prognosis, ongoing studies in the literature, and future perspectives related to the use of DM bearings employed in primary THA. DM bearings are primarily designed to address one of the major concerns in THA: Instability of the prosthetic hip. Instability is both for the surgeon and the patient a devastating postoperative complication, leading to significant pain and subsequent apprehension by the patient and may require revision surgeries. The use of DM implants poses the worry of wear-related complications, such as accelerated polyethylene wear and osteolysis, which also pose challenges to long-term implant survival. This technique has seen a steady rise in recent years, with multiple studies reporting favorable outcomes. The incidence of their utilization varies among institutions and surgeons, reflecting differing preferences and patient populations. The diagnosis of instability and wear-related complications in THA often involves clinical assessment, imaging modalities such as X-rays, computed tomography scans, and sometimes advanced imaging techniques like magnetic resonance imaging. DM bearings can be considered as an option when patients present neurologic pathologies such as Parkinson's disease or recurrent dislocations after THA. DM bearings provide an additional articulation point within the implant, facilitating a greater range of motion and inherent stability. This design allows for reduced risk of dislocation and improved functional outcomes. Various implant manufacturers offer different designs and sizes of DM bearings to suit individual patient needs. Current literature suggests that the use of DM bearings in primary THA has demonstrated promising outcomes in terms of enhanced stability, reduced dislocation rates, and improved patient satisfaction. However, long-term studies with larger patient cohorts are necessary to establish the durability and longevity of these implants. Several ongoing studies are investigating the role of DM bearings in primary THA. These studies focus on evaluating long-term implant survivorship, assessing wear patterns, analyzing patient-reported outcomes, and comparing the effectiveness of DM bearings with traditional THA designs. The future of DM bearings in primary THA holds potential for further advancements. Research efforts are aimed at refining implant materials, optimizing designs, and studying the influence of surgical techniques on implant performance. Additionally, continued investigation into the long-term outcomes and cost-effectiveness of DM bearings will play a crucial role in shaping their future use. While further research is warranted, the current evidence supports their potential as a beneficial solution in improving surgical outcomes and patient satisfaction.