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Bassam A Masri - One of the best experts on this subject based on the ideXlab platform.
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patient satisfaction and functional status after treatment of infection at the site of a total knee arthroplasty with use of the prostalac articulating spacer
Journal of Bone and Joint Surgery American Volume, 2003Co-Authors: R Dominic M Meek, Bassam A Masri, David J Dunlop, Donald S Garbuz, Nelson V Greidanus, R W Mcgraw, Clive P DuncanAbstract:Background: Two-stage exchange arthroplasty remains the standard treatment of infection at the site of a total knee arthroplasty. The clinical and functional outcomes associated with the use of an articulating antibiotic spacer for two-stage revision for infection are not well established. We conducted a retrospective study to evaluate the outcomes associated with the use of the PROSTALAC articulating spacer between the first and second stages. Methods: Fifty-eight patients underwent two-stage revision total knee arthroplasty for infection between January 1997 and December 1999. Of these, fifty-four were alive at the time of follow-up and forty-seven were available for inclusion in the present retrospective study. In all patients, a prosthesis of antibiotic-loaded Acrylic Cement (the PROSTALAC system) was implanted during the first stage after debridement. The amount of osteolysis that occurred between the stages and the range of motion of the knee joint were measured. After two years of follow-up, outcomes were assessed with use of the WOMAC, Oxford-12, and SF-12 instruments as well as a satisfaction questionnaire. Results: At a minimum of two years (average, forty-one months) after revision arthroplasty, two patients (4%) had had a recurrence of infection. The amount of bone loss was unchanged between stages, and the range of movement of the knee improved from 78.2° before the first stage to 87.1° at two years. The average normalized WOMAC function and pain scores were 68.9 and 77.1, respectively; the average Oxford-12 score was 67.3; the average SF-12 mental and physical scores were 53.7 and 41.2, respectively; and the average satisfaction score was 71.7. Conclusion: A revision operation for infection at the site of a total knee replaCement with use of an articulating spacer was associated with reasonable function and satisfaction scores. These findings may be related to the articulating features of the PROSTALAC system, which permits full active movement of the knee in the early postoperative period. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.
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hip prosthesis of antibiotic loaded Acrylic Cement for the treatment of infections following total hip arthroplasty
Journal of Bone and Joint Surgery American Volume, 2002Co-Authors: Steven J Wentworth, Clive P Duncan, Bassam A Masri, Carleton SouthworthAbstract:Infection continues to be one of the most feared complications of total hip arthroplasty. Despite many advances over the past three decades, this infrequent complication continues to undermine an otherwise highly predictable and successful procedure. The prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC; DePuy, Warsaw, Indiana) is a temporary hip-replaCement articulated spacer intended for patients who need a two-stage exchange arthroplasty for the treatment of a confirmed or suspected infection at the site of a total hip replaCement. This device has received approval from the United States Food and Drug Administration as a humanitarian use device. (This humanitarian device has been authorized by federal law as a short-term total hip replaCement [THR] in patients who need a two-stage procedure to treat a confirmed infection of their THR and where vancomycin and tobramycin are the most appropriate antibiotics for treatment of the infection based on the susceptibility pattern of the infecting microorganism[s]. The effectiveness of this device for this use has not been determined.) The early experience with 135 patients who were treated with the PROSTALAC implant is reported. Initial experience has also been reported in previous publications 1-2. The PROSTALAC system ( Fig. 1 ) is a temporary total hip replaCement prosthesis that is used as a first-stage exchange articulated spacer and provides for local delivery of antibiotics at the infection site. It comprises a short or long-stem cobalt-chrome-alloy core femoral implant; a one-piece, ultra-high molecular weight polyethylene, snap-fit acetabular component; a standard 32-mm cobalt-chrome modular femoral head; and a polymethylmethacrylate stem centralizer. Polymethylmethacrylate bone Cement and the antibiotic in powder form are the remaining components of the system. Fig. 1: The PROSTALAC system (A) consists of a snap-fit, all-polyethylene Cemented acetabular component with a metal endoskeleton, femoral head, and centralizer that are inserted into a mold (B) that is …
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long term elution of antibiotics from bone Cement an in vivo study using the prosthesis of antibiotic loaded Acrylic Cement prostalac system
Journal of Arthroplasty, 1998Co-Authors: Bassam A Masri, Clive P Duncan, Christopher P BeauchampAbstract:A prospective study of 49 patients undergoing a modified 2-stage exchange arthroplasty for infected total hip and knee arthroplasties using the prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC) system with a variety of doses of tobramycin and vancomycin was performed. The intra-articular concentrations of tobramycin and vancomycin were measured at the time of removal of the PROSTALAC temporary spacer and reimplantation of a definitive joint arthroplasty prosthesis, at a mean 118 days following initial implantation. The 95% confidence interval of the intra-articular concentration of tobramycin (4.35-123.88 mg/L) was entirely above the breakpoint sensitivity limit for sensitive organisms when at least 3.6 g of tobramycin was used per package of bone-Cement but was entirely below it when at most 2.4 g was used. Vancomycin elution was not as good; however, detectable levels were still present in most patients. There was a statistically significant increase in the elution of vancomycin when the dose of tobramycin was increased from at most 2.4 g to at least 3.6 g. The dose of vancomycin in the Cement did not influence the elution of either tobramycin or vancomycin. On the basis of these results, the use of at least 3.6 g of tobramycin and 1 g of vancomycin per package of bone-Cement is recommended when antibiotic-loaded Cement spacers are used in 2-stage exchange arthroplasty for infected total hip and knee arthroplasties.
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treatment of infection associated with segmental bone loss in the proximal part of the femur in two stages with use of an antibiotic loaded interval prosthesis
Journal of Bone and Joint Surgery American Volume, 1998Co-Authors: Alastair Younger, Cltve P. Duncan, Bassam A MasriAbstract:Treatment of an infection at the site of a total hip replaCement associated with extensive loss of the proximal part of the femur is a challenging problem. In the present preliminary report, we describe the results after use of a prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC) in thirty such hips. The purpose of the prosthesis, which acts as an internal splint, is to maintain the length of the femur as well as the range of motion of the joint and the mobility of the patient between stages. A local level of antibiotics is maintained by the antibiotic-coated surface. A PROSTALAC with a Cement-on-Cement articulation was used in the first fifteen hips (Group I) in the study, and a custom metal-on-polyethylene articulating PROSTALAC was inserted in the subsequent fifteen hips (Group II). One patient who had a recurrent infection was managed with a second two-stage exchange and was included in both groups. Between stages, the average limb-length discrepancy was twenty-five millimeters despite a loss of more than 25 per cent of the femur in nineteen limbs. Sixteen patients were discharged home and seven, to a community hospital between stages. Six patients in Group I and only one in Group II were hospitalized for the entire course of treatment. The total duration of hospitalization for both stages averaged thirty-eight days. Twenty-eight patients were mobile even though they did not bear weight on the involved limb between stages: three patients used a cane, fifteen used crutches, and ten used a walker. Twenty-six patients reported no, slight, or moderate pain in the thigh, groin, or buttock between stages. The average Harris hip score before the first stage of the operation was 23 points (range, 0 to 63 points), which improved to 74 points (range, 40 to 91 points) at an average of forty-seven months (range, twenty-four to 114 months) postoperatively. Two patients died of unrelated causes before two years (the minimum follow-up period) had elapsed and were excluded from the final analysis; they had no evidence of recurrent infection. Of the remaining twenty-eight hips, twenty-seven (96 per cent) had no evidence of infection at the most recent follow-up examination.
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effect of varying surface patterns on antibiotic elution from antibiotic loaded bone Cement
Journal of Arthroplasty, 1995Co-Authors: Christopher P Beauchamp, Clive P Duncan, Bassam A Masri, Nancy J Paris, Jennifer ArntorpAbstract:In an effort to improve the antibiotic elution characteristics of the prosthesis of antibiotic-loaded Acrylic Cement, an in vitro study was conducted. Tobramycin-loaded bone Cement blocks of three different surface patterns with different surface area-to-volume ratios were used. The elution of tobramycin over a 2-month period was investigated. There was a gradual decline in the tobramycin elution rate over time. The surface pattern with the increased surface area-to-volume ratio showed a significant increase in the tobramycin elution rate over the first week of the study. The surface pattern with ridges but no change in the surface area-to-volume ratio did not result in a statistically significant increase in the tobramycin elution rate.
Clive P Duncan - One of the best experts on this subject based on the ideXlab platform.
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patient satisfaction and functional status after treatment of infection at the site of a total knee arthroplasty with use of the prostalac articulating spacer
Journal of Bone and Joint Surgery American Volume, 2003Co-Authors: R Dominic M Meek, Bassam A Masri, David J Dunlop, Donald S Garbuz, Nelson V Greidanus, R W Mcgraw, Clive P DuncanAbstract:Background: Two-stage exchange arthroplasty remains the standard treatment of infection at the site of a total knee arthroplasty. The clinical and functional outcomes associated with the use of an articulating antibiotic spacer for two-stage revision for infection are not well established. We conducted a retrospective study to evaluate the outcomes associated with the use of the PROSTALAC articulating spacer between the first and second stages. Methods: Fifty-eight patients underwent two-stage revision total knee arthroplasty for infection between January 1997 and December 1999. Of these, fifty-four were alive at the time of follow-up and forty-seven were available for inclusion in the present retrospective study. In all patients, a prosthesis of antibiotic-loaded Acrylic Cement (the PROSTALAC system) was implanted during the first stage after debridement. The amount of osteolysis that occurred between the stages and the range of motion of the knee joint were measured. After two years of follow-up, outcomes were assessed with use of the WOMAC, Oxford-12, and SF-12 instruments as well as a satisfaction questionnaire. Results: At a minimum of two years (average, forty-one months) after revision arthroplasty, two patients (4%) had had a recurrence of infection. The amount of bone loss was unchanged between stages, and the range of movement of the knee improved from 78.2° before the first stage to 87.1° at two years. The average normalized WOMAC function and pain scores were 68.9 and 77.1, respectively; the average Oxford-12 score was 67.3; the average SF-12 mental and physical scores were 53.7 and 41.2, respectively; and the average satisfaction score was 71.7. Conclusion: A revision operation for infection at the site of a total knee replaCement with use of an articulating spacer was associated with reasonable function and satisfaction scores. These findings may be related to the articulating features of the PROSTALAC system, which permits full active movement of the knee in the early postoperative period. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.
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hip prosthesis of antibiotic loaded Acrylic Cement for the treatment of infections following total hip arthroplasty
Journal of Bone and Joint Surgery American Volume, 2002Co-Authors: Steven J Wentworth, Clive P Duncan, Bassam A Masri, Carleton SouthworthAbstract:Infection continues to be one of the most feared complications of total hip arthroplasty. Despite many advances over the past three decades, this infrequent complication continues to undermine an otherwise highly predictable and successful procedure. The prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC; DePuy, Warsaw, Indiana) is a temporary hip-replaCement articulated spacer intended for patients who need a two-stage exchange arthroplasty for the treatment of a confirmed or suspected infection at the site of a total hip replaCement. This device has received approval from the United States Food and Drug Administration as a humanitarian use device. (This humanitarian device has been authorized by federal law as a short-term total hip replaCement [THR] in patients who need a two-stage procedure to treat a confirmed infection of their THR and where vancomycin and tobramycin are the most appropriate antibiotics for treatment of the infection based on the susceptibility pattern of the infecting microorganism[s]. The effectiveness of this device for this use has not been determined.) The early experience with 135 patients who were treated with the PROSTALAC implant is reported. Initial experience has also been reported in previous publications 1-2. The PROSTALAC system ( Fig. 1 ) is a temporary total hip replaCement prosthesis that is used as a first-stage exchange articulated spacer and provides for local delivery of antibiotics at the infection site. It comprises a short or long-stem cobalt-chrome-alloy core femoral implant; a one-piece, ultra-high molecular weight polyethylene, snap-fit acetabular component; a standard 32-mm cobalt-chrome modular femoral head; and a polymethylmethacrylate stem centralizer. Polymethylmethacrylate bone Cement and the antibiotic in powder form are the remaining components of the system. Fig. 1: The PROSTALAC system (A) consists of a snap-fit, all-polyethylene Cemented acetabular component with a metal endoskeleton, femoral head, and centralizer that are inserted into a mold (B) that is …
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long term elution of antibiotics from bone Cement an in vivo study using the prosthesis of antibiotic loaded Acrylic Cement prostalac system
Journal of Arthroplasty, 1998Co-Authors: Bassam A Masri, Clive P Duncan, Christopher P BeauchampAbstract:A prospective study of 49 patients undergoing a modified 2-stage exchange arthroplasty for infected total hip and knee arthroplasties using the prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC) system with a variety of doses of tobramycin and vancomycin was performed. The intra-articular concentrations of tobramycin and vancomycin were measured at the time of removal of the PROSTALAC temporary spacer and reimplantation of a definitive joint arthroplasty prosthesis, at a mean 118 days following initial implantation. The 95% confidence interval of the intra-articular concentration of tobramycin (4.35-123.88 mg/L) was entirely above the breakpoint sensitivity limit for sensitive organisms when at least 3.6 g of tobramycin was used per package of bone-Cement but was entirely below it when at most 2.4 g was used. Vancomycin elution was not as good; however, detectable levels were still present in most patients. There was a statistically significant increase in the elution of vancomycin when the dose of tobramycin was increased from at most 2.4 g to at least 3.6 g. The dose of vancomycin in the Cement did not influence the elution of either tobramycin or vancomycin. On the basis of these results, the use of at least 3.6 g of tobramycin and 1 g of vancomycin per package of bone-Cement is recommended when antibiotic-loaded Cement spacers are used in 2-stage exchange arthroplasty for infected total hip and knee arthroplasties.
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Bacterial growth on antibiotic-loaded Acrylic Cement: A prospective in vivo retrieval study
Journal of Arthroplasty, 1995Co-Authors: Richard Kendall, Clive P Duncan, Christopher P BeauchampAbstract:Abstract Twenty-three patients with intraoperative culture-proven periprosthetic infection of the hip or knee were enrolled in a prospective Cement retrieval study. All were treated with a two-stage technique using antibiotic-loaded Acrylic Cement as an antibiotic depot. Staphylococcus epidermidis was the most commonly isolated organism (19 of 23 cases). Cement and tissue were examined at second-stage revision for the presence of viable organisms. In this series, no organisms were isolated from the surface of the Cement, a 100% concordance with the tissue cultures. A subsequent failure rate of 4.4% (1 case) was seen in this series. Investigation suggests this may represent reinfection from a new strain of organism rather than failure of eradication of the original infection.
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effect of varying surface patterns on antibiotic elution from antibiotic loaded bone Cement
Journal of Arthroplasty, 1995Co-Authors: Christopher P Beauchamp, Clive P Duncan, Bassam A Masri, Nancy J Paris, Jennifer ArntorpAbstract:In an effort to improve the antibiotic elution characteristics of the prosthesis of antibiotic-loaded Acrylic Cement, an in vitro study was conducted. Tobramycin-loaded bone Cement blocks of three different surface patterns with different surface area-to-volume ratios were used. The elution of tobramycin over a 2-month period was investigated. There was a gradual decline in the tobramycin elution rate over time. The surface pattern with the increased surface area-to-volume ratio showed a significant increase in the tobramycin elution rate over the first week of the study. The surface pattern with ridges but no change in the surface area-to-volume ratio did not result in a statistically significant increase in the tobramycin elution rate.
P Hernigou - One of the best experts on this subject based on the ideXlab platform.
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open wedge tibial osteotomy with Acrylic bone Cement as bone substitute
Knee, 2001Co-Authors: P HernigouAbstract:Abstract We studied the results of 245 valgus producing high tibial osteotomies performed with the use of an opening wedge technique and rigid internal fixation followed by early passive and active motion of the knee. Previous studies have used iliac bone grafts or hemicollastasis held by an external fixator for opening the osteotomy. In our series the opening was obtained by a block of Cement interposed in the postero-medial part of the osteotomy. This series confirms that the opening wedge osteotomy allows good accuracy for the correction. Ninety-three percent of the knees had a correction adjusted between 180 and 187° for the hip–knee–ankle angle. Survivorship analysis showed an expected rate of survival, with conversion to a total knee on the end point, of 94% at 5 years, 85% at 10 years and 68% at 15 years. Conversion to a total knee arthroplasty was accomplished without difficulty in the patients who had this procedure done. We recommend opening wedge tibial osteotomy with Acrylic Cement bone Cement as bone substitute, rigid internal fixation, and early motion for patients who undergo high tibial osteotomy.
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open wedge tibial osteotomy with Acrylic bone Cement as bone substitute
Knee, 2001Co-Authors: P HernigouAbstract:We studied the results of 245 valgus producing high tibial osteotomies performed with the use of an opening wedge technique and rigid internal fixation followed by early passive and active motion of the knee. Previous studies have used iliac bone grafts or hemicollastasis held by an external fixator for opening the osteotomy. In our series the opening was obtained by a block of Cement interposed in the postero-medial part of the osteotomy. This series confirms that the opening wedge osteotomy allows good accuracy for the correction. Ninety-three percent of the knees had a correction adjusted between 180 and 187 degrees for the hip-knee-ankle angle. Survivorship analysis showed an expected rate of survival, with conversion to a total knee on the end point, of 94% at 5 years, 85% at 10 years and 68% at 15 years. Conversion to a total knee arthroplasty was accomplished without difficulty in the patients who had this procedure done. We recommend opening wedge tibial osteotomy with Acrylic Cement bone Cement as bone substitute, rigid internal fixation, and early motion for patients who undergo high tibial osteotomy.
Rik Huiskes - One of the best experts on this subject based on the ideXlab platform.
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Acrylic Cement creeps but does not allow much subsidence of femoral stems
Journal of Bone and Joint Surgery American Volume, 1997Co-Authors: Nico Verdonschot, Rik HuiskesAbstract:It has been suggested that the endurance of Cemented femoral reconstructions in total hip arthroplasty is affected by the creep of Acrylic Cement, but it is not known to what extent Cement creeps under loading conditions in vivo, or how this affects load transfer. We have simulated the long-term creep properties of Acrylic Cement in finite-element models of femoral stem constructs and analysed their effects. We investigated whether subsidence rates measured in vivo could be explained by creep of Acrylic Cement, and if polished, unbonded, stems accommodated creep better than bonded stems. Our findings showed that polished prostheses subsided only about 50 μm as a result of Cement creep. The long-term prosthetic subsidence rates caused by creep of Acrylic Cement are therefore very small and do not explain the excessive migration rates which have sometimes been reported. Cement creep did, however, relax Cement stresses and create a more favourable stress distribution at the interfaces. These trends were found around both the bonded and unbonded stems. Our results did not confirm that polished, unbonded, stems accommodated creep better than bonded stems in terms of Cement and interface stress patterns.
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Subsidence of THA stems due to Acrylic Cement creep is extremely sensitive to interface friction
Journal of biomechanics, 1996Co-Authors: Nico Verdonschot, Rik HuiskesAbstract:Acrylic Cement, used to fixate total hip arthroplasty (THA), creeps under dynamic and static loading conditions. As a result, THA stems which are debonded from the Cement, may gradually subside, depending on their shape and surface roughness. The purpose of this study was to evaluate the relationship among dynamic load, creep characteristics, interface friction, and subsidence patterns. A laboratory model consisting of a metal tapered cone, surrounded by a Cement mantle, was developed. The cone was gradually compressed in the Cement by a dynamic, sinusoidal axial force, cycling between 0 and 7 kN for 1.7 million cycles at a frequency of 1 Hz. Subsidence and Cement strain were monitored. Two tapers were tested in this way. The relationships among subsidence, creep properties and interface friction were evaluated from a finite element (FE) model, used to simulate the experiments. In this model, the creep properties obtained in dynamic and static, tension and compression experiments measured earlier, were used. The subsidence patterns of both tapers were similar, but one subsided more than the other (380 vs 630 microns). Both subsided stepwise instead of continuous, with a frequency much smaller than that of the applied load. The characteristics of the subsidence and Cement-strain patterns could be reproduced by the FE model, but not with great numerical precision. The stepwise subsidence could be explained by slip-stick mechanisms at the interface starting distally and gradually working towards proximal. Variations in friction from 0.25 to 0.50 reduced the total subsidence and the step frequency by about 50%. It was concluded that FE-models used to simulate the mechanical endurance characteristics of THA reconstructions, extended to incorporate Cement creep, produce realistic results. These results showed that prosthetic subsidence under dynamic loads occurs due to Cement creep. The extent of the subsidence is extremely sensitive to interface friction, hence to small variations in surface roughness and Cement constitution. This may explain the relatively large variation of in vivo prosthetic subsidence rates reported in the literature.
Christopher P Beauchamp - One of the best experts on this subject based on the ideXlab platform.
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long term elution of antibiotics from bone Cement an in vivo study using the prosthesis of antibiotic loaded Acrylic Cement prostalac system
Journal of Arthroplasty, 1998Co-Authors: Bassam A Masri, Clive P Duncan, Christopher P BeauchampAbstract:A prospective study of 49 patients undergoing a modified 2-stage exchange arthroplasty for infected total hip and knee arthroplasties using the prosthesis of antibiotic-loaded Acrylic Cement (PROSTALAC) system with a variety of doses of tobramycin and vancomycin was performed. The intra-articular concentrations of tobramycin and vancomycin were measured at the time of removal of the PROSTALAC temporary spacer and reimplantation of a definitive joint arthroplasty prosthesis, at a mean 118 days following initial implantation. The 95% confidence interval of the intra-articular concentration of tobramycin (4.35-123.88 mg/L) was entirely above the breakpoint sensitivity limit for sensitive organisms when at least 3.6 g of tobramycin was used per package of bone-Cement but was entirely below it when at most 2.4 g was used. Vancomycin elution was not as good; however, detectable levels were still present in most patients. There was a statistically significant increase in the elution of vancomycin when the dose of tobramycin was increased from at most 2.4 g to at least 3.6 g. The dose of vancomycin in the Cement did not influence the elution of either tobramycin or vancomycin. On the basis of these results, the use of at least 3.6 g of tobramycin and 1 g of vancomycin per package of bone-Cement is recommended when antibiotic-loaded Cement spacers are used in 2-stage exchange arthroplasty for infected total hip and knee arthroplasties.
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Bacterial growth on antibiotic-loaded Acrylic Cement: A prospective in vivo retrieval study
Journal of Arthroplasty, 1995Co-Authors: Richard Kendall, Clive P Duncan, Christopher P BeauchampAbstract:Abstract Twenty-three patients with intraoperative culture-proven periprosthetic infection of the hip or knee were enrolled in a prospective Cement retrieval study. All were treated with a two-stage technique using antibiotic-loaded Acrylic Cement as an antibiotic depot. Staphylococcus epidermidis was the most commonly isolated organism (19 of 23 cases). Cement and tissue were examined at second-stage revision for the presence of viable organisms. In this series, no organisms were isolated from the surface of the Cement, a 100% concordance with the tissue cultures. A subsequent failure rate of 4.4% (1 case) was seen in this series. Investigation suggests this may represent reinfection from a new strain of organism rather than failure of eradication of the original infection.
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effect of varying surface patterns on antibiotic elution from antibiotic loaded bone Cement
Journal of Arthroplasty, 1995Co-Authors: Christopher P Beauchamp, Clive P Duncan, Bassam A Masri, Nancy J Paris, Jennifer ArntorpAbstract:In an effort to improve the antibiotic elution characteristics of the prosthesis of antibiotic-loaded Acrylic Cement, an in vitro study was conducted. Tobramycin-loaded bone Cement blocks of three different surface patterns with different surface area-to-volume ratios were used. The elution of tobramycin over a 2-month period was investigated. There was a gradual decline in the tobramycin elution rate over time. The surface pattern with the increased surface area-to-volume ratio showed a significant increase in the tobramycin elution rate over the first week of the study. The surface pattern with ridges but no change in the surface area-to-volume ratio did not result in a statistically significant increase in the tobramycin elution rate.
