DAIR for Infected Total Hip Arthroplasty - Does the Operative Approach Influence the Functional Result?

Study Overview
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Brief Summary
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The functional outcome and quality of life after treatment for an infected hip arthroplasty have been found to be significantly worse compared to an uncomplicated arthroplasty. However, the type of revision surgery chosen to treat the infection plays a role for the functional outcome. The concept of DAIR (debridement, antibiotics and implant retention) has been shown to yield god results with respect to infection control in cases of early infection with a stable implant and better functional results than a to-stage revision. In patients where infection control was achieved after just one DAIR procedure the functional outcome was comparable to an uncomplicated primary arthroplasty. However, it is not known if the operative approach used for the primary and revision surgery plays a role for the functional result after treatment of an infected total hip arthroplasty with DAIR. The project's aim is to investigate if the choice of the operative approach (transgluteal or posterior) for the primary hip replacement and the revision surgery has an influence on the functional result after debridement and implant retention for an infected total hip replacement.

Detailed Description
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Potential study participants will be identified in the Norwegian Arthroplasty Register. Patients who have been revised once for an infected total hip arthroplasty with debridement and implant retention and in whom either the transgluteal og posterior operative approach was used in both procedures will be selected. The potential participants will be contacted by letter. They will be asked for written informed consent and to fill out three questionnaires: the Hip Disability Osteoarthritis Score (HOOS), which also allows for the calculation of the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), the EQ-5D (quality of life) and a questionnaire asking about confirmation that the patient only has been revised once for his/her infected arthroplasty, about limping, other complications (nerve injury, dislocation, reoperation for other causes than infection), if the infection is considered to have been eradicated and overall satisfaction. The data recorded in the Norwegian Arthroplasty Register will be used in a multiple linear regression analysis to evaluate if the surgical approach is an independent factor influencing the outcome measures.

Official Title
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Debridement, Antibiotics and Implant Retention (DAIR) for Infected Total Hip Arthroplasty- Does the Operative Approach Influence the Functional Result?

Conditions
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Hip Prosthesis Infection, Arthroplasty Complications

Intervention / Treatment
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* Procedure: Transgluteal approach to the hip joint
* Procedure: Posterior approach to the hip joint


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The infected total hip arthroplasty has only been revised once. The revision procedure was a debridement and implant retention. Both, the primary and the revision procedure were performed through the same surgical approach; either the transgluteal or the posterior approach. Exclusion Criteria: No written informed consent.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Transgluteal approach to the hip joint<br>Patients who have been revised once for an infected total hip replacement with debridement and implant retention and in whom both the primary hip arthroplasty and the revision procedure were performed through a transgluteal approach. | Procedure: Transgluteal approach to the hip joint<br>* Operative approach to the hip joint where the abductors are partly detached from the greater trochanter and the hip joint is approached through the anterior part of the capsule.<br>* Other names: Direct lateral approach to the hip joint;|
| Posterior approach to the hip joint<br>Patients who have been revised once for an infected total hip replacement with debridement and implant retention and in whom both the primary hip arthroplasty and the revision procedure were performed through a posterior approach. | Procedure: Posterior approach to the hip joint<br>* Operative approach to the hip joint where the short external rotators are detached from the greater trochanter and the hip joint is approached through the posterior part of the capsule.<br>* Other names: Posterolateral approach to the hip joint;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Function subscale score of the WOMAC | Function subscale score of the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| WOMAC score | Western Ontario and McMaster Universities osteoarthritis index score | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 
| HOOS | Hip Disability Osteoarthritis Score | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 
| EQ-5D score | Quality of life score | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 
| Limping | Patient reported limping on the side of the revised total hip replacement. | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 
| Other complications | Patient reported nerve injury, dislocation, reoperation for other causes than infection. | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 
| Overall satisfaction | Overall satisfaction with the revised total hip replacement assessed by questionnaire. | At minimum 1 year, on average 5 year follow-up from the DAIR procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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DAIR, Transgluteal approach, Posterior approach