Imaging of Joint Replacement Complications by PET/CT

Study Overview
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Brief Summary
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Total hip replacement is the well-established surgical method for treatment of hip osteoarthritis and related diseases. The outcome of the procedure is commonly satisfactory and most patients will not need any revision surgery. However, the procedure has its complications, including (1) periprosthetic infection, (2) mechanical loosening caused by wear particles and (3) adverse reaction caused by metal ions released from metal-on-metal bearing surfaces. The unsolved clinical problem is related to the differential diagnosis of these conditions. The purpose of this prospective clinical study is to compare the efficacy of two techniques of PET/CT imaging in the differential diagnosis of these complications. Positron Emission Tomography (PET)/Computed Tomography (CT) imaging, performed during a single day, will include the head-to-head comparison of 18F-Fluoro-D-Glucose (18F-FDG) PET/CT and 68Gallium-citrate (68Ga-citrate) PET/CT imaging.

Detailed Description
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(68Ga) gallium citrate is a novel PET tracer aimed for detection of skeletal infections. It has not been previously applied to diagnose periprosthetic joint infections in arthroplasty patients. This exploratory prospective study, representing the first of its kind, examines the use of 68Ga-citrate as a diagnostic tool of periprosthetic infections aside with 18F-FDG tracer as the standard reference. The first study group (n=10) will include total hip replacement patients without infection. The recruited patients should suffer from pain and/or functional impairment due to adverse reaction to metal debris (ARMD) caused by metal-on-metal bearings. The diagnosis of ARMD should be based on metal artifact reduction sequence magnetic resonance imaging (MARS-MRI). The patients will undergo the same-day comparison of the two PET/CT tracers. The second study group (n=10) will include total hip replacement patients with bacteriologically confirmed periprosthetic joint infection. The third group (n=10) will include patients with aseptic loosening of total hip prosthesis.

Official Title
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Prospective Intra-individual Comparison of 18F-FDG and 68Ga-citrate PET/CT in Symptomatic Total Hip Arthroplasty Patients

Conditions
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Adverse Reactions to Metal Debris, Infection of Total Hip Joint Prosthesis, Mechanical Loosening of Prosthetic Joint

Intervention / Treatment
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* Diagnostic Test: 68Ga-citrate and 18F-FDG PET/CT imaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients with uncemented total hip replacement American Society of Anesthesiology score I-III Group 1: local symptoms and MRI findings of the operated hip fulfilling the criteria of ARMD due to metal-on-metal bearings of the hip prosthesis, infection ruled out Group 2: bacteriologically verified periprosthetic infection of the hip prosthesis Group 3: local symptoms and radiographic findings of the hip prosthesis fulfilling the criteria of aseptic mechanical implant loosening, infection ruled out Exclusion Criteria: any related condition of the index hip which requires immediate surgical intervention, such as a septic infection or a periprosthetic fracture any systemic disorder or condition (ASA IV) which makes the patient an unlikely candidate for revision surgery of the affected hip implant

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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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Intra-individual comparison of two diagnostic PET imaging tracers
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Adverse reaction to metal debris<br>68Ga-citrate and 19F-FDG PET/CT imaging of hip replacement patients with adverse tissue reactions to metal debris | Diagnostic Test: 68Ga-citrate and 18F-FDG PET/CT imaging<br>* Single-day study of the two PET tracers<br>|
| Active Comparator: Periprosthetic joint infection<br>68Ga-citrate and 19F-FDG PET/CT imaging of hip replacement patients with periprosthetic joint infection | Diagnostic Test: 68Ga-citrate and 18F-FDG PET/CT imaging<br>* Single-day study of the two PET tracers<br>|
| Active Comparator: Aseptic mechanical implant loosening<br>68Ga-citrate and 19F-FDG PET/CT imaging of patients with aseptic mechanical loosening of hip prosthesis | Diagnostic Test: 68Ga-citrate and 18F-FDG PET/CT imaging<br>* Single-day study of the two PET tracers<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Exclusion of the presence of periprosthetic joint infection in ARMD patients | The two PET imaging techniques are expected to rule out infection in patients with ARMD due to metal-on-metal bearings | Clinical follow-up of 3 years or more after PET/CT imaging |