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In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy
Published on: July 2, 2021
Dual poly liner mobility optimizes wear and stability in THA: opposes
Matthew C Lyons1, Steven J MacDonald
1Division of Orthopedic Surgery, University of Western Ontario & London Health Sciences Centre, London, Ontario, Canada.
Orthopedics
|September 10, 2011
Summary
Dual-mobility acetabular components in total hip arthroplasty (THA) may increase dislocation risk due to intraprosthetic dislocation. Studies show these liners do not necessarily improve wear or avoid osteolysis compared to conventional THA.
Area of Science:
- Orthopedic Surgery
- Biomaterials Science
- Medical Device Engineering
Background:
- Total hip arthroplasty (THA) effectively treats arthrosis but faces complications like dislocation and osteolysis.
- Dual-mobility acetabular components are proposed to enhance stability and reduce wear in THA.
- These components aim to increase range of motion (ROM) by utilizing a larger effective femoral head size.
Purpose of the Study:
- To evaluate the efficacy and complications associated with dual-mobility acetabular components in total hip arthroplasty.
- To compare the stability, wear, and osteolysis rates of dual-mobility liners against conventional THA.
- To assess the suitability of dual-mobility liners for revision THA.
Main Methods:
- Review of literature and retrieval studies on dual-mobility acetabular components.
- Analysis of reported incidence rates for instability, dislocation, and intraprosthetic dislocation.
- Examination of wear and osteolysis data in comparison to conventional THA.
Main Results:
- Dual-mobility liners report a 0.4% incidence of instability in primary THA, comparable to conventional THA.
- A unique complication, intraprosthetic dislocation, occurs at a reported incidence of 3.6% due to polyethylene wear.
- Retrieval studies indicate dual-mobility liners do not consistently avoid wear or osteolysis, challenging proposed benefits.
Conclusions:
- Dual-mobility acetabular components introduce a significant risk of intraprosthetic dislocation, exceeding rates seen in conventional THA.
- The purported benefits of improved wear characteristics and reduced osteolysis are not consistently supported by current evidence.
- The monoblock design and potential for instability raise questions about the utility of dual-mobility liners, particularly in revision THA.
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