Study protocol: Effectiveness of dual-mobility cups compared with uni-polar cups for preventing dislocation after primary total hip arthroplasty in elderly patients — design of a randomized controlled trial nested in the Dutch Arthroplasty Registry

Acta Orthopaedica, vol. 91, pp. 514–519

Abstract

Background and purpose - Dislocation is the leading reason for early revision surgery after total hip arthroplasty (THA). The dual-mobility (DM) cup was developed to provide more stability and mechanically reduce the risk of dislocation. Despite the increased use of DM cups, high-quality evidence of their (cost-)effectiveness is lacking. The primary objective of this randomized controlled trial (RCT) is to investigate whether there is a difference in the number of hip dislocations following primary THA, using the posterolateral approach, with a DM cup compared with a unipolar (UP) cup in elderly patients 1 year after surgery. Secondary outcomes include the number of revision surgeries, patient-reported outcome measures (PROMs), and cost-effectiveness.Methods and analysis - This is a prospective multicenter nationwide, single-blinded RCT nested in the Dutch Arthroplasty Registry. Patients ≥ 70 years old, undergoing elective primary THA using the posterolateral approach, will be eligible. After written informed consent, 1,100 participants will be randomly allocated to the intervention or control group. The intervention group receives a THA with a DM cup and the control group a THA with a UP cup. PROMs are collected preoperatively, and 3 months, 1 and 2 years postoperatively. Primary outcome is the difference in number of dislocations between the UP and DM cup within 1 year, reported in the registry (revisions), or by the patients (closed or open reduction). Data will be analyzed using multilevel models as appropriate for each outcome (linear/logistic/survival). An economic evaluation will be performed from the healthcare and societal perspective, for dislocation and quality adjusted life years (QALYs).Trial registration - This RCT is registered at www.clinicaltrials.gov with identification number NCT04031820.

Authors 8

1. Loes W A H van Beers

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

2. Bart C. H. van der Wal

   University Medical Center Utrecht

   Affiliation as printed

   University Medical Center Utrecht, Utrecht;

   University Medical Center Utrecht, Utrecht,

3. Tess Glastra van Loon

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

4. Dirk Jan F. Moojen

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

5. Marieke F. van Wier

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

6. Amanda D Klaassen

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

7. Nienke Willemien Willigenburg

   OLVG

   Affiliation as printed

   OLVG, Amsterdam;

   OLVG, Amsterdam

8. Rudolf Wilhelm Poolman Aachen

   Leiden University Medical Center · Medisch Centrum Leeuwarden · St. Antonius Ziekenhuis · OLVG · Diakonessenhuis hospital · Isala · St. Anna Ziekenhuis

   Affiliation as printed

   LUMC, Leiden, the Netherlands

   OLVG, Amsterdam;

   A de Gast, Diakonessenhuis, Utrecht; D H R Kempen, OLVG, Amsterdam; H B Ettema, Isala, Zwolle; J L C van Susante, Rijnstate, Arnhem; LUMC, Leiden, the Netherlands Collaborator group: E Scheijbeler, OLVG, Amsterdam; M van Dijk, St Antonius Ziekenhuis, Utrecht; OLVG, Amsterdam;; T D Berendes, Meander MC, Amersfoort; T Gosens, ETZ, Tilburg; W P Zijlstra, Medisch Centrum Leeuwarden, Leeuwarden; W van der Weegen, St Anna Ziekenhuis, Geldrop, The Netherlands