Fully Constrained Acetabular Liner vs. Dual Mobility Hip Joint in the Surgical Treatment of Metastatic Bone Disease of the Hip

The purpose of the current study is to investigate whether dual mobility liners are non-inferior til constrained liners regarding the post-operative hip joint dislocation risk following total hip replacement in patients with metastatic bone disease of the hip.

The use of constrained liners in total hip arthroplasty (THA) in patients with metastatic bone disease of the hip (MBD) has increased at our department in recent years to avoid hip dislocation in this high-risk population. Hip surgeons seldom recommend the use of constrained liners in primary surgery due to the risk of polyethylene wear and high revision rates. An alternative to constrained liners are dual mobility cups, which have been shown to decrease the risk of dislocation in other high-risk THA operations such as revision THA and THA in hip fracture patients, while providing the added benefit of a less restricted range of motion of the joint. This study will investigate whether dual mobility cups are non-inferior to constrained liners regarding the post-operative joint dislocation risk in patients with MBD.

Inclusion Criteria: * Diagnosed with metastatic bone disease of the hip defined as bone lesions in the proximal femur because of secondary malignant growth of a primary cancer located elsewhere or bone lesions in the proximal femur due to hematological malignancies * Determined eligible for total hip arthroplasty for metastatic bone disease of the hip and is planned to undergo surgery at the study site * Provides informed consent prior to initiation of any study-specific activities/procedures Exclusion Criteria: * Previous osteosynthesis or endoprosthetic surgery of the ipsilateral hip * Pelvic reconstruction of the ipsilateral hip * Total femoral replacement of the ipsilateral femur * It is not surgically viable to insert an acetabular cup and/or a femoral stem * Subject is currently or has previously been enrolled in this study * Subject is incapable of understanding the patient information or unable to provide informed consent