We updated the design of this site on September 25th. Learn more.
Show more
ClinicalTrials.gov
ClinicalTrials.gov Menu

Articulating Versus Static Antibiotic Loaded Spacers for the Treatment of Prosthetic Knee Infection

This study is currently recruiting participants.
Verified April 2017 by Peter N. Chalmers, MD, Rush University Medical Center
Sponsor:
ClinicalTrials.gov Identifier:
NCT01373112
First Posted: June 14, 2011
Last Update Posted: April 11, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
Collaborators:
Central DuPage Hospital
Joint Implant Surgeons, Inc.
Thomas Jefferson University
Information provided by (Responsible Party):
Peter N. Chalmers, MD, Rush University Medical Center
June 6, 2011
June 14, 2011
April 11, 2017
December 2011
August 2018   (Final data collection date for primary outcome measure)
Range of motion [ Time Frame: Outcomes will be collected until 2 years post-operatively. ]
Same as current
Complete list of historical versions of study NCT01373112 on ClinicalTrials.gov Archive Site
  • Knee Society Score [ Time Frame: Outcomes will be collected until 2 years post-operatively. ]
  • Operative time [ Time Frame: Outcomes will be collected until 2 years post-operatively. ]
Same as current
Not Provided
Not Provided
 
Articulating Versus Static Antibiotic Loaded Spacers for the Treatment of Prosthetic Knee Infection
Articulating Versus Static Antibiotic Loaded Spacers for the Treatment of Prosthetic Knee Infection

Infection remains a difficult-to-treat complication of total knee arthroplasty. The gold standard treatment is two-stage removal of the prosthesis with later replacement of permanent implants. The first stage consists of removal of the infected arthroplasty components and the surrounding devitalized tissue, copious pulsed irrigation, and placement of a temporary antibiotic-impregnated cement spacer. This spacer typically is left in place six weeks, during which time the patient receives intravenous antibiotics. After the surgeon feels that the infection has been eradicated, or if the patient requires repeat debridement, a second operative procedure is performed. While the use of an antibiotic-loaded spacer is well accepted, whether the spacer should immobilize the knee (a so-called "static" spacer) or allow for range of motion (a so-called "articulating" spacer) is controversial. Proponents of articulating spacers argue that they prevent scarring of the musculature surrounding the knee resulting in easier reimplantation, improved long-term knee function, and improved range of motion. Proponents of static spacers argue that immobilization of the periarticular soft tissues aids in clearance of the infection and is simpler to fashion intraoperatively. While good results have been described with both methods, comparative trials have been conflicting as to whether spacer design alters knee function, operative time, and range of motion. Equipoise exists within the literature, and no randomized clinical trial has been conducted to evaluate this issue.

The purpose of this study is to compare articulating and static antibiotic-impregnated spacers for the treatment of chronic periprosthetic infection complicating total knee arthroplasty through a prospective, randomized clinical trial. The goals of this trial are to determine the effect of spacer design upon eradication of infection, knee function, ease of reimplantation, and range of motion. The investigators hypothesize that articulating spacers will provide shorter operative times at reimplantation, while improving knee function and range of motion.

After diagnosis of infection and informed consent, patients will be taken to the operating room. After anesthetization, patients will be randomized to either an articulating spacer or a static spacer. Randomization will be performed by prepared opaque envelopes administered by a nonparticipant in the study. After a complete debridement of devitalized tissue, explantation of the infected components and any associated cement, either an articulating or static spacer will be placed. All spacers will be formed of 3 g of Vancomycin and 1 g of Tobramycin for each 40 g packet of cement. Articulating spacers will be formed of antibiotic impregnated cement using the Stage One system (Biomet, Warsaw, IN). Static spacers will be hand-made to fit the femoral and tibial exposed metaphyses as a solid block with associated antibiotic cement coated tibial and femoral intramedullary rod, such that knee motion will be minimized.

Post-operatively, all patients will be made touch-down weight bearing protected with a walker or crutches. If a static spacer is placed, patients will be immobilized using with a knee immobilizer. If an articulating spacer is utilized, range of motion will be allowed to the limits of stability as determined in the operating room and protected with a hinged knee brace. At the time of reoperation, the joint will be aspirated and multiple cultures obtained along with intraoperative histopathological analysis to evaluate for persistent infection.

Data collected preoperatively will include age, gender, laterality, etiology of knee degeneration, comorbidities, Knee Society score, and infecting organisms. The Knee Society score has been used extensively in the study of revision knee arthroplasty and has been found to be reliable and valid and will be determined pre-operatively and at all follow-up visits.

Data collected at the time of implant removal and reimplantation will include operative time, blood loss, and need for an extensile exposure. Radiographs performed immediately following and just prior to reimplantation will be reviewed to determine if the spacer utilized has caused bone loss; bone loss to the cut bony surfaces will be confirmed intraoperatively. At each follow-up visit radiographic appearance, the Knee Society Score, knee range of motion, recurrence of infection, and the need for revision or reoperation of any kind on the knee will be determined.

All portions of this study will be part of conventional care except for randomization to either a static or articulating spacer. Which type of spacer is used currently depends upon the judgment of the attending surgeons and both are used routinely.

The primary outcome variable will be range of motion. A power analysis was conducted with the assistance of Dr. Mario Moric at Rush using range of motion as our primary outcome variable, with standard deviations culled from two of the largest series to date -Van Thiel and colleagues (2010) and Fehring and colleagues (2000). For an 80% chance of detecting a predetermined clinically significant difference of 10 degrees, 53 patients per group, 106 patients total, will be needed. To account for attrition, our target sample size will be 140 patients.

Interventional
Not Provided
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
  • Osteoarthritis
  • Knee Infection
  • Prosthetic Joint Infection
  • Complications; Arthroplasty, Infection or Inflammation
  • Complications; Arthroplasty
  • Procedure: Static Spacer
    After diagnosis of infection and informed consent, patients will be taken to the operating room. After anesthetization, patients will be randomized to either an articulating spacer or a static spacer. Randomization will be performed by prepared opaque envelopes administered by a nonparticipant in the study. After a complete debridement of devitalized tissue, explantation of the infected components and any associated cement, either an articulating or static spacer will be placed. All spacers will be formed of 3 g of Vancomycin and 1 g of Tobramycin for each 40 g packet of cement. Static spacers will be hand-made to fit the femoral and tibial exposed metaphyses as a solid block with associated antibiotic cement coated tibial and femoral intramedullary rod, such that knee motion will be minimized.
  • Procedure: Articulating Spacer
    After diagnosis of infection and informed consent, patients will be taken to the operating room. After anesthetization, patients will be randomized to either an articulating spacer or a static spacer. Randomization will be performed by prepared opaque envelopes administered by a nonparticipant in the study. After a complete debridement of devitalized tissue, explantation of the infected components and any associated cement, either an articulating or static spacer will be placed. All spacers will be formed of 3 g of Vancomycin and 1 g of Tobramycin for each 40 g packet of cement. Articulating spacers will be formed of antibiotic impregnated cement using the Stage One system (Biomet, Warsaw, IN).
  • Experimental: Static Spacer
    After diagnosis of infection and informed consent, patients will be taken to the operating room. After anesthetization, patients will be randomized to either an articulating spacer or a static spacer. Randomization will be performed by prepared opaque envelopes administered by a nonparticipant in the study. After a complete debridement of devitalized tissue, explantation of the infected components and any associated cement, either an articulating or static spacer will be placed. All spacers will be formed of 3 g of Vancomycin and 1 g of Tobramycin for each 40 g packet of cement. Static spacers will be hand-made to fit the femoral and tibial exposed metaphyses as a solid block with associated antibiotic cement coated tibial and femoral intramedullary rod, such that knee motion will be minimized.
    Intervention: Procedure: Static Spacer
  • Experimental: Articulating Spacer
    After diagnosis of infection and informed consent, patients will be taken to the operating room. After anesthetization, patients will be randomized to either an articulating spacer or a static spacer. Randomization will be performed by prepared opaque envelopes administered by a nonparticipant in the study. After a complete debridement of devitalized tissue, explantation of the infected components and any associated cement, either an articulating or static spacer will be placed. All spacers will be formed of 3 g of Vancomycin and 1 g of Tobramycin for each 40 g packet of cement. Articulating spacers will be formed of antibiotic impregnated cement using the Stage One system (Biomet, Warsaw, IN).
    Intervention: Procedure: Articulating Spacer

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruiting
140
August 2018
August 2018   (Final data collection date for primary outcome measure)

Inclusion Criteria:

1) Diagnosis of a periprosthetic joint infection of a primary total knee arthroplasty with a planned two-stage exchange procedure.

Exclusion Criteria:

  1. Infection of a revision as opposed to a primary total knee arthroplasty
  2. Medically unfit for operative intervention
  3. Extensive bone loss preventing the use of an articulating spacer
  4. Soft tissue defects that prevent the use of an articulating spacer
  5. Known allergy to polymethylmethacrylate, tobramycin or vancomycin.
Sexes Eligible for Study: All
18 Years to 100 Years   (Adult, Senior)
No
Contact: Peter N Chalmers, MD 3129425000 peter_chalmers@rush.edu
Contact: Craig Della Valle, MD 3129425000
United States
 
 
NCT01373112
SPACERKNEE
No
Not Provided
Not Provided
Peter N. Chalmers, MD, Rush University Medical Center
Rush University Medical Center
  • Central DuPage Hospital
  • Joint Implant Surgeons, Inc.
  • Thomas Jefferson University
Principal Investigator: Peter Chalmers, MD Rush University Medical Center
Principal Investigator: Craig Della Valle, MD Rush University Medical Center
Principal Investigator: Scott Sporer, MD Rush University Medical Center
Principal Investigator: Adolph Lombardi, MD Joint Implant Surgeons, Inc.
Principal Investigator: Keith Berend, MD Joint Implant Surgeons, Inc.
Principal Investigator: Matt Austin, MD Thomas Jefferson Hospital
Rush University Medical Center
April 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP
To Top