Static vs. Articulating Antibiotic Spacer for Periprosthetic Joint Infection in Total Knee Arthroplasty

Study Overview
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Brief Summary
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The primary aim of the study is to compare two techniques for treatment of total knee infection: resection total knee arthroplasty with an articulating (motion in the joint) spacer and resection total knee arthroplasty with a static (no motion in the joint) spacer.

Official Title
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A Randomized Clinical Trial of Static Versus Articulating Antibiotic Spacer for Treatment of Periprosthetic Joint Infection in Total Knee Arthroplasty

Conditions
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Prosthetic Joint Infection of the Knee

Intervention / Treatment
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* Device: Static Antibiotic Spacer Surgical Implant
* Device: Articulating Antibiotic Spacer Surgical Implant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Male or female age 18 to 100 years of age. Preoperative diagnosis of bacterial infection by culture which would include a preoperative aspiration and at least three intraoperative cultures. The preoperative aspiration would also be sent for a cell count with differential. All patients would have an erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) drawn in the preoperative phase. Patients with a negative preoperative aspiration, but an actively draining wound or draining sinus tract, would be considered as infected. Intraoperative histopathology would also be obtained in all cases of infected total knee replacement at the time of the resection. Intact extensor mechanism. Adequate soft tissue envelope (no requirement for soft tissue coverage such as a muscle flap or skin graft) Adequate bone stock for knee reconstruction Medical fitness for staged knee reconstruction Exclusion Criteria Known Atypical infection (mycobacterial or fungal) Extensor mechanism disruption Inadequate soft tissue envelope requiring muscle flap or skin grafting Inadequate bone stock (T3 or F3 by the Anderson Orthopaedic Research Institute (AORI) classification) Medical status precluding staged knee reconstruction Requirement for hinged knee reconstruction at the time of reimplantation Pregnant women - for women of child bearing age, a negative pregnancy test will be needed prior to enrollment to the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Static Antibiotic Spacer<br>Patient with prosthetic joint infection of their knee will have a two stage joint replacement surgery with the Static Antibiotic Spacer Surgical Implant being used to treat the joint infection until the second stage of surgery which will replace the joint after the infection is treated. | Device: Static Antibiotic Spacer Surgical Implant<br>* Joint spacer for treatment of joint infection<br>|
| Active Comparator: Articulating Antibiotic Spacer<br>Patient with prosthetic joint infection of their knee will have a two stage joint replacement surgery with the Articulating Antibiotic Spacer Surgical Implant being used to treat the joint infection until the second stage of surgery which will replace the joint after the infection is treated. | Device: Articulating Antibiotic Spacer Surgical Implant<br>* Joint spacer for treatment of joint infection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Subjects With Repeat Infections | The rate of repeat infections after re-implantation Total Knee Arthroplasty. | 1 year post-operatively | 
| Change in Total Knee Replacement Functional Scores | Functional scores were measured using the Knee Society Score, a clinical standard for rating the outcome of total knee replacements. Scores range from 0 -100, where a higher score reflects a more positive outcome for the subject. | baseline, 1 year post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pre-operative Range of Motion (ROM) | The degree of knee flexion was measured pre-operatively. | baseline | 
| Post-operative Range of Motion (ROM) | The degree of knee flexion was measured one year post-operatively. | 1 year post-operatively |