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Trilogy-constrained acetabular component for recurrent dislocation
Annette Vest Andersen1, Anne Grete Kjersgaard1, Søren Solgaard1
1Department of Orthopedic Surgery, Gentofte Hospital, Niels Andersens Vej 65, 2900 Hellerup, Denmark.
Insights
Constrained acetabular liners effectively manage recurrent dislocations after total hip replacement. This study shows good outcomes for patients with well-fixed components, despite a low rate of further dislocations.
Area of Science:
- Orthopedic Surgery
- Biomaterials Engineering
- Reconstructive Surgery
Background:
- Recurrent dislocations pose a significant challenge following total hip replacement (THR).
- Existing treatment options for recurrent dislocations can be limited.
- Constrained acetabular liners offer a potential solution for instability in THR.
Purpose of the Study:
- To evaluate the efficacy of Trilogy- or Trilogy-Longevity-constrained acetabular liners in patients experiencing recurrent dislocations after THR.
- To assess the functional outcomes and complication rates associated with these constrained liners.
Main Methods:
- A retrospective study of 32 patients who received constrained acetabular liners for recurrent dislocations.
- Liners were inserted into well-fixed Trilogy acetabular shells using a snap-fit mechanism.
- Follow-up included clinical assessment (Harris Hip Score) and radiographic evaluation.
Main Results:
- A low rate of further dislocations (12%) was observed post-implantation.
- One patient required revision surgery for an acetabular shell loosening.
- Radiographic findings included one case of a loose locking ring and other minor findings, with no definitively loose components.
Conclusions:
- Constrained acetabular liners are an effective method for managing recurrent dislocations in total hip replacement patients with well-fixed components.
- The use of these liners demonstrates a favorable outcome in preventing further instability.
- Further investigation into long-term component fixation and potential complications is warranted.
Abstract:
32 patients received a Trilogy- or Trilogy-Longevity-constrained acetabular liner for recurrent dislocations after total hip replacement. The constrained liner was inserted into a well-fixed Trilogy acetabular shell with snap fit. At 1.8-year followup (range 3-63 months), 4 patients had suffered further dislocation(s) (12%), and one patient had revision surgery for a loosened acetabular shell. Radiologic evaluation detected no definitively loose components, but one patient with progressing radiolucent lines around the femoral component and one patient with an acetabular cyst were found, as well as a patient with a loose locking ring (but otherwise no failure). The nineteen patients who were available for the present followup had a mean Harris Hip Score of 81. The constrained liner is an effective method of dealing with recurrent dislocations in well-fixed components.
