Patient Reported Outcome After Dislocation of a Primary THA

Study Overview
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Brief Summary
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The aim is to compare QOL and hip specific outcome measures in patients with a single or recurrent episode(s) of THA dislocation and patients with a THA without any dislocation.

Detailed Description
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Knowledge about the patient's own perception of both general health and more hip-related issues after experiencing a hip dislocation is lacking (19). Hip surgeons need this information in order to incorporate it with other objective aspects, when advising patients with their first hip dislocation. Due to the large study population, this study will provide solid information of what to expect after a hip dislocation and be the largest study ever conducted within this topic. Depending on the results, this study may change the path we choose to advise for our patients after single or recurrent dislocations. A matched case-control study involving the share of THA patients with at least 1 episode of hip dislocation. The patients had undergone primary surgery in the 5-year period from 01.01.2010 - 31.12.2014 and subsequent dislocation was evaluated in a 2-year follow-up period. Given a 3-5% approximated incidence of dislocation, 1100-1800 cases will have been identified. Patients are subdivided in groups depending on the number of dislocations and one group containing THA revisions. In order to be included, a time frame of at least 0,5 year since the last episode of dislocation or surgery must have passed. A matched control group of patients with primary THA without any event of dislocation are located from the original 5-year period of primary surgery. They will be matched with the group of patients with dislocation, regarding to: Age (+/- 5 years) Gender Date of surgery and hospital The study will be conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. After 01.01.2019, all patients included will be receiving 3 questionnaires (a generic - EQ-5D, a hip-specific - HOOS, and an activity scale - UCLA) by e-boks (a mandatory secure email system couplet to the patient's CPR number). Some elderly are exempt and will instead receive the questionnaires by regular mail and a pre-labeled return envelope is attached. Reminders are sent after 2 months.

Official Title
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Patient Reported Outcome After Dislocation of a Primary THA

Conditions
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Quality of Life, Hip Dislocation

Intervention / Treatment
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* Other: No intervention.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with one or more events of hip dislocation after a primary THA controls with a primary THA without events of hip dislocation Exclusion Criteria: -

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Single dislocation.<br>Patients with a single postoperative hip dislocation without subsequent revision surgery. | Other: No intervention.<br>* No intervention.<br>|
| Recurrent dislocation.<br>Patients with two or more postoperative hip dislocations without subsequent revision surgery. | Other: No intervention.<br>* No intervention.<br>|
| Revision due to dislocation.<br>Patients with one or more postoperative hip dislocations with subsequent revision surgery due to recurrent instability. | Other: No intervention.<br>* No intervention.<br>|
| Controls.<br>Matched patients without postoperative hip dislocation or revision of any reason. | Other: No intervention.<br>* No intervention.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| QOL (Quality of life) | Measured by the EQ-5D questionnaire. | 9 years | 
| Hip function | Measured by the HOOS questionnaire. | 9 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Activity | Measured by the UCLA activity questionnaire. | 9 years |