Antibiotic-loaded Cement Spacer Research Articles

Antimicrobial activity of gentamicin and vancomycin combination in joint fluids after antibiotic-loaded cement spacer implantation in two-stage revision surgery

Gentamicin (G) and vancomycin (V) concentrations in joints fluids obtained from patients during the first 24 hours after implantation of antibiotic-loaded polymethylmethacrylate (PMMA) spacers in two-stage revision for infected arthroplasty, and the inhibitory activity of joint fluids against different multiresistant clinical isolates were studied. A total of 12 patients undergoing two-stage revision surgery with implantation of industrial G spacers added with different amounts of V was studied. Serum and joint fluid samples were collected 1, 4, and 24 hours after spacer implantation. Antibiotics concentrations and joint bactericidal titer (JBT) of combination were determined against multiresistant staphylococcal strains. The local release of G and V from PMMA cement seemed prompt and effective. Serum levels were below the limit of detection. The same joint fluid showed different activity according to the susceptibility of the pathogens tested. Gentamicin and V were released from spacers at bactericidal concentrations exerting a strong inhibition against methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (CoNS) strains.

Artificial Fusion of Infected Total Knee Arthroplasty Using a Flexible Intramedullary Rod Bundle and an Antibiotic-Loaded Cement Spacer

Multiple total knee arthroplasty (TKA) failure resulting from a recurrent infection is a challenging problem. Knee arthrodesis is one treatment option that normally involves the application of an external fixator, plate fixation, and intramedullary nailing. However, these approaches are not always successful, and a reinfection is a risk, particularly in older, medically compromised patients. This paper reports a new arthrodesis technique that uses a bundle of flexible intramedullary rods and an antibiotic-loaded cement spacer. This technique was used in two cases of multiple TKA failure that resulted from a recurrent infection. The procedure was successful in both cases with no evidence of rod or cement failure. Two advantages of this procedure are infection eradication and mechanical strength. However, this procedure should only be used for medically compromised elderly patients at high risk of rerevision TKA failure resulting from persistent periprosthetic infection because rod fracture or loosening can occur with time.

One‐stage Versus Two‐stage Exchange

Liaison: Paul Lichstein MD, MSLeaders: Thorsten Gehrke MD (International), Adolph Lombardi MD, FACS (US), Carlo RomanoMD (International), Ian Stockley MB, ChB, MD, FRCS (International)Delegates: George Babis MD, Jerzy Bialecki MD, La´szlo´ Bucsi MD, Xu Cai MD, Li Cao MD, Briande Beaubien MD, Johannes Erhardt MD, Stuart Goodman MD, PhD, FRCSC, FACS, FBSE,William Jiranek MD, Peter Keogh, David Lewallen MD, MS, Paul Manner MD, WojciechMarczynski MD, J. Bohannon Mason MD, Kevin Mulhall MB, MCh, FRCSI, Wayne PaproskyMD, Preetesh Patel MD, Francisco Piccaluga MD, Gregory Polkowski MD, Luis Pulido MD, IanStockley MBBS, ChB, FRCS, Juan Suarez MD, Fritz Thorey MD, Rashid Tikhilov MD, JobDiego Velazquez MD, Heinz Winkler MD

Antibiotic-loaded cement spacer for treatment of Klebsiella infected total hip and knee arthroplasty

Infection following total hip arthroplasty (THA) or total knee arthoplasty (TKA) may have devastating consequences. Some bacterial strains are often encountered as agents of these infections, others occur less frequently but are sometimes burdened with more severe complications. Kebsiella spp. are uncommon causes of THA or TKA infection. The aim of this study was to identify an effective treatment algorithm for multidrug resistant Kebsiella spp. caused THA or TKA infections. During the 3-year period, from January 1 2009 to December 31 2011, we registered and treated 5 patients with THA or TKA multidrug resistant Klebsiella spp. caused infection. All the patients were primarily operated in other institutions, and were admitted in our clinic after the onset of infection symptoms. In three of the cases Klebsiella infection was complicated by additional infection (Staphyloccocus aureus, Pseudomonas aeruginosa and Serratia marscescens). In 3 of the cases we performed revision arthroplasty after double exchange of antibiotic-loaded articulating cement spacer, and in 2 of the cases the standard two-stage revision approach with one antibiotic cement spacer exchange was applied. The mean length of follow-up after reimplantation surgery was 17.1 months (range 2-31 months). One patient died 2 months after the final reimplantation procedure. The initial Klebsiella infection was eradicated in all the patients. At the end follow-up after definitive reimplantation, the patients had no clinical, laboratory or microbiological parameters positive for active infection. According to our experience with multidrug-resistant Klebsiella TKA/THA infections, two-stage approach, in some cases with double articulating cement spacer exchange prior to definitive reimplantation, is the most effective treatment option.

The two-stage standard in revision total hip replacement

Two-stage exchange remains the gold standard for treatment of peri-prosthetic joint infection after total hip replacement (THR). In the first stage, all components and associated cement if present are removed, an aggressive debridement is undertaken including a complete synovectomy, and an antibiotic-loaded cement spacer is put in place. Patients are then treated with six weeks of parenteral antibiotics, followed by an 'antibiotic free period' to help ensure the infection has been eradicated. If the clinical evaluation and serum inflammatory markers suggest the infection has resolved, then the second stage can be completed, which involves removal of the cement spacer, repeat debridement, and placement of a new THR.

Dislocation of Preformed Antibiotic-Loaded Cement Spacers (Spacer-G): Etiological Factors and Clinical Prognosis

This study assesses the factors associated with the dislocation of the Spacer-G and its clinical prognosis. Seventy-four spacers were reviewed. Acetabular bone defects, proximal femoral cementation of the spacer and its relationship to the size of the head spacer were not associated with dislocation. The only variable that it was possible to associate with dislocation was when the previous stem, prior to the spacer placement, was a cemented stem. In patients who experienced a dislocation, infection was not cured during the interim period more frequently than patients who had not experienced a dislocation (P=0.001) and the final clinical hip evaluation was also worse (P<0.001). The study concludes that the surgeon should assess different surgical aspects in order to avoid mechanical complications such as dislocation and its consequences.

Industrially Prefabricated Cement Spacers: Do Vancomycin- and Gentamicin-impregnated Spacers Offer Any Advantage?

Industrially preformed antibiotic-loaded cement spacers are useful to facilitate the second stage of two-stage exchange arthroplasty for infected THAs and TKAs. However, whether gentamicin alone or a combination of antibiotics (such as vancomycin and gentamicin) is more effective is not known. We therefore sought to compare industrially prefabricated spacers containing either gentamicin or gentamicin and vancomycin with respect to (1) infection control, (2) complications, and (3) quality of life, pain, and patient satisfaction. We performed a review of 51 patients with chronic infections treated at one center using either gentamicin or vancomycin and gentamicin-prefabricated spacers. The former were used exclusively from January 2006 until May 2009, and the latter from June 2009 until July 2011, and there was no overlap. We collected data on demographics, immunologic status (McPherson classification), prosthetic joint infection location, type of prosthesis, microbiologic results, and time between stages. We evaluated the primary outcome of infection control or recurrence after at least 12 months followup. We also recorded complications. Each patient completed a quality-of-life survey, VAS, and a self-administered satisfaction scale. The overall infection control rate was 83% after a mean followup of 35 months (range, 12.4-64.7 months). There were no differences between gentamicin and vancomycin and gentamicin spacers in terms of infection eradication (80 % versus 85 %, respectively; p = 0.73), nor in terms of complications, quality of life, pain, or satisfaction scores. Prefabricated, antibiotic-loaded cement spacers has been proven effective for infection control in TKAs and THAs but with the numbers available, we did not find any differences between a gentamicin or vancomycin and gentamicin-prefabricated spacer, and therefore, we are unable to validate the superiority of the combination of vancomycin and gentamicin over gentamicin alone. Because of the higher costs involved with vancomycin and gentamicin spacers, and the potential risks of unselective use of vancomycin, further comparative studies are necessary to evaluate their role in the treatment of infected THAs or TKAs. Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Fungal prosthetic joint infection after total knee arthroplasty

Fungal prosthetic joint infection after total knee arthroplasty (TKA) is a rare complication. Lacunae exist in the management of this complication. 62 year old lady presented with pain and swelling in left knee and was diagnosed as Candida tropicalis fungal infection after TKA. She underwent debridement, resection arthroplasty and antifungal plus antibiotic loaded cement spacer insertion, antifungal therapy with fluconazole followed by delayed revision TKA and further fluconazole therapy. Total duration of fluconazole therapy was 30 weeks. At 2 year followup, she has pain less range of motion of 10°-90° and there is no evidence of recurrence of infection.

Acrylic bone cement: current concept review

Acrylic bone cement has had for years an important role in orthopedic surgery. Polymethylmethacrylate (PMMA) has been extended from the ophthalmological and dental fields to orthopedics, as acrylic cement used for fixation of prosthetic implants, for remodeling osteoporotic, neoplastic and vertebral fractures repair. The PMMA bone cement is a good carrier for sustained antibiotic release in the site of infection. Joint prostheses chronic infection requires surgical removal of the implant, in order to eradicate the infection process. This can be performed in the same surgical time (one-stage procedure) or in two separate steps (two-stage procedure, which involves the use of an antibiotic-loaded cement spacer). The mechanical and functional characteristics of the spacers allow a good joint range of motion, weight-bearing in selected cases and a sustained release of antibiotic at the site of infection. The improvement of fixation devices in recent years was not accompanied by the improvement of elderly bone quality. Some studies have tested the use of PMMA bone cement or calcium phosphate as augmentation support of internal fixation of these fractures. Over the past 20 years, experimental study of acrylic biomaterials (bone cement, bioglass ceramic, cement additives, absorbable cement, antibiotic spacers) has been of particular importance, offering numerous models and projects.

Retaining well-fixed cementless stem in the treatment of infected hip arthroplasty

Sir—I have read the Acta article: Retaining well-fixed cementless stem in the treatment of infected hip arthroplasty” by Lee et al. (2013). The authors present outcome in 19 patients with infected hip arthroplasties and a well-fixed cementless stem intraoperatively tested by a stem retractor. Treatment consisted of removal of the acetabular cup, liner and head, and implantation of a cup of a cement spacer. At a mean follow-up of 4 years 15 of 17 patients had no recurrence of infection. The authors stated that there have been no results of stem-retaining 2-staged revision in the literature. However, we have published a similar study reporting on 13 patients with infected hip arthroplasties and well-fixed stems (Anagnostakos et al. 2010). In all cases a preoperative bone scintigraphy excluded involvement of the stem. Intraoperatively, the stem fixation was also tested by a stem retractor. Treatment consisted of removal of the acetabular cup, liner and head, and implantation of an antibiotic-loaded cement spacer head. At a mean follow-up of 5 years the infection was healed in 11 of 12 cases.

Sonication of antibiotic-loaded cement spacers in a two-stage revision protocol for infected joint arthroplasty

BackgroundCulturing of the sonication fluid of removed implants has proven to be more sensitive than conventional periprosthetic tissue culture for the microbiological diagnosis of prosthetic joint infection. Since bacteria surviving on antibiotic-loaded cement spacers used in a two-stage exchange protocol for infected arthroplasties may cause the persistence of infection, in this study we asked whether the sonication also could be used to identify bacteria on antibiotic-loaded cement spacers removed at the second surgical stage during a two-stage exchange procedure to confirm whether or not the prosthetic joint infection had been eradicated.MethodsWe cultured the sonication fluid of cement spacers that had been originally implanted in a two-stage exchange protocol in 21 patients (mean age, 66 years) affected by prosthetic joint infection (16 total knee prostheses and 5 hip prostheses). The cement spacers were vortexed for 30 seconds and then subjected to sonication (frequency 35–40 KHz). The resulting sonicate fluid was cultured for aerobic and anaerobic bacteria.ResultsThe sonication fluid culture of the removed spacer was positive in six patients (29%), with isolation of methicillin-sensible Staphylococcus Aureus (MSSA) in three cases, methicillin-resistant Staphylococcus Aureus (MRSA) in one case and Pseudomonas Aeruginosa in two cases. In three of these positive cases, the traditional culture of periprosthetic tissue was negative. Two patients with positive sonication culture of the spacer were successfully treated by early debridement of the revision prosthesis and systemic antibiotic therapy. In three patients a knee arthrodesis was planned and performed as the second surgical stage. In two of them the infection was caused by highly resistant Pseudomonas Aeruginosa. The other patient with a MSSA infection had been poorly compliant with the systemic antibiotic therapy due to her mental impairment. The patient originally affected by MRSA infection of his primary hip arthroplasty developed recurrent infection of his revision prosthesis and eventually underwent Girdlestone arthroplasty.ConclusionsThe sonication culture can be used to discover any bacteria on the antibiotic-loaded cement spacer during a two-stage exchange protocol, thus permitting the adoption of timely treatment options, such as the early prosthetic debridment.

A novel technique to preserve range of motion in two-stage revision of infected total knee arthroplasty

Two-stage revision represents the gold standard in the treatment of infected total knee arthroplasty. Different techniques have been proposed, mostly not preserving range of motion. An articulated antibiotic-loaded cement spacer made in association with two unicompartmental implants has been used as an alternative to a static spacer in an effort to retain as much movement as possible between the stages in young, high-demand patients with preserved ROM. We evaluated nine consecutive patients with a mean age of 66.5 years. The second stage was performed after lab tests returned to normal and culture proved negative. Mean follow-up was 4.6 years. Mean ROM from a preoperative value of 105.6° was 103.5° after the first stage, and improved to 110.0° after the definitive implant. Mean Knee Society score was 27.6 preoperatively improving to 86.4 points postoperatively. WOMAC score showed that six patients were very satisfied with the overall result of their reimplanted knee, three subjects were somewhat satisfied. No recurrence of infection, no significant radiolucent lines or osteolysis were recorded at clinical and radiological follow-up and the patients were satisfied with the outcome. Results indicated that this technique may ensure the advantages of a static spacer, but allow a greater ROM and better functional recovery. It may be considered as a viable option in selected cases even though the higher costs of two unicompartmental implants should be considered in the light of other aspects, such as prolonged hospital stay and rehabilitation in revision of infected total knee arthroplasty.

The Influence of Storage Temperature on the Antibiotic Release of Vancomycin-Loaded Polymethylmethacrylate

Periprosthetic joint infection is devastating and increases medical expenditure and socioeconomic burden. Antibiotic-loaded cement spacer is useful in the interim period before the reimplantation surgery. Prefabricated antibiotic-loaded cement spacers can decrease operation time but have been limitedly used clinically. In the literature, there is no clear recommendation on the storage temperature for the prefabricated cement spacers. We used an in vitro model to analyze whether the storage temperature at 25°C, 4°C, or −20°C for 2 weeks or 3 months could affect the release of vancomycin from the cement. We found that the storage temperature and time had no significant effects on the pattern and amount of vancomycin release. The patterns of vancomycin release from the cement stored at different temperatures were similar with an abrupt release in the first 3 days and steadily declined in the following period. This study provides a preliminary result to justify the storage of fabricating antibiotic-loaded cement spacer sterilely packed at room temperature. Further studies to examine the effects of storage temperature on the mechanical strength and the release pattern of other antibiotics should be done to provide more evidence to support the clinical use of prefabricated ready-to-use antibiotic-loaded cement spacer.

Periprosthetic Joint Infection: Clinical and Bench

Periprosthetic joint infection (PJI) is a devastating complication for the patient and the health care providers. Its incidence is between 1% and 3% in primary and 4% and 6% in revision total joint arthroplasties. The diagnosis can be straightforward with purulent discharge from the joint but may also be confusing especially when associated with medical morbidities. Often, infection leads to multiple operations, prolonged use of antibiotics, extensive utilization of medical resources, and substantial social, economic, or even psychological impacts on the patients, family, hospitals, physicians, and payers. It is estimated that the direct medical cost for treating a PJI is 3 times to the medical cost without infection in revisions and 10 times to the medical cost with uneventful primary cases. As the demand for total joint arthroplasties and the burden of PJI increase globally, knowledge and technologies for detecting, preventing, and managing PJI need to be shared to provide better care to patients. In this special issue, we included studies of economic analysis on the treatment of PJI (D. Hernandez-Vaquero et al.), animal models of implant-associated infection (M. Haenle et al. and A. I. Stavrakis et al.), methods to improve the diagnosis (D. S. Evangelopoulos et al. and M. S. Lee et al.), efficacy and the potential use of preformed antibiotic-loaded cement spacer (D. Regis et al. and D. W. Chen et al.), and clinical studies of using antibiotic-loaded cement spacer in hip and knee infections (S. S. Ahmad et al. and K. Uchiyama et al.). The notion to publish the special issue is to bridge the basic studies with the clinical studies. Because PJI is a great mimic that many failed joint arthroplasties initially attributed to aseptic loosening are found to be caused by infection in many occasions. M. Haenle et al. and A. I. Stavrakis et al. highlighted the importance of biofilm formation and the possibility of implant-associated infection with comparatively low dose of bacterial inocula. Sonication of the retrieved prosthesis (D. S. Evangelopoulos et al.) and the use of molecular probes for bacteria-specific genes (M. S. Lee et al.) can improve the accuracy of diagnosis. It therefore can help differentiating easy-to-treat or difficult-to-treat cases (S. S. Ahmad et al.) and the choice of antibiotics in fabricating the cement spacers. This special issue cannot cover all the issues dealing with PJI. However, by increasing the clinicians and surgeons awareness about PJI, the burdens and challenges could be met by putting more efforts to prevent infection, to design novel bacteria-resistant implants, to improve diagnostic sensitivity and accuracy, to make better antibiotic-loaded spacers, and to develop strategies in treating drug-resistant strains or fungal infections. These works need the collaboration between academic researchers and clinicians to translate basic science to clinical practice. Mel S. Lee Andrew Freiberg Wolfgang Klauser Christopher S. Mow Shin-Yoon Kim

Nuove prospettive sperimentali e cliniche per il cemento osseo acrilico: “review” delle moderne potenzialità di un materiale caro ai chirurghi ortopedici, veicolo di farmaci e sostituto dell’osso

Acrylic bone cement has had for years an important role in orthopedic surgery. Polymethylmethacrylate (PMMA) has been extended from the ophthalmologic and dental fields to orthopedics, as acrylic cement used for fixation of prosthetic implants, for remodeling osteoporotic, neoplastic or metastatic areas and for vertebral fractures repair. The PMMA bone cement is a good carrier for sustained release of antibiotic in the site of infection. Joint prostheses chronic infection requires surgical removal of the implant, in order to eradicate the infection process. This can be performed in the same surgical time (one-stage procedure) or in two separate steps (twostage procedure, which involves the use of an antibiotic-loaded cement spacer). The mechanical and functional characteristics of the spacers allow a good joint range of motion, weight-bearing in selected cases, and a sustained release of antibiotic in the site of infection. The improvement of fixation devices in recent years was not accompanied by the improvement of elderly bone quality. Some studies have tested the use of PMMA bone cement or calcium-phosphate as augmentation-support of internal fixation of these fractures. Over the past 20 years, experimental study of acrylic biomaterials (bone cement, bioglass ceramic, cement additives, absorbable cement, antibiotic spacers) has been of particular importance, offering numerous models and projects:

Antibiotic-loaded articulating cement spacer in two-stage revision for infected total knee arthroplasty

Objective To detail our early experience on a modified two-stage revison using articulating antibiotic-loaded cement spacer (AALCS) for late periprosthetic infection of total knee arthroplasty (TKA).Methods From January 2006 to February 2009,a series of 21 patients (21 knees) underwent twostage revision knee arthroplasty for late infected TKA.There were 8 males and 13 females,aged from 56 to 83 years (average,64.4 years).In the first stage,each patient underwent radical debridement,removal of all components and cement,and implantation of articulating cement spacer containing vancomycin.Graduated knee motion and partial weight bearing activity were encouraged in the interval period.Each patient received an individual systemic organism-sensitive antimicrobial therapy for 4.9 weeks (range,2-8 weeks) followed by a second-stage revision TKA.All the patients were regularly followed-up using the American Knee Society Scoring System.Results All patients were followed up for 17 to 54 months (average,32.2 months).At final follow-up,the knee society score,function score,pain score and range of motion (ROM) of knee were significantly improved compared with those before operation.Meanwhile,there was no significant increase in the degree of extension lag.The average interval period was 11.5 weeks (range,6-32 weeks).No change of bone defect volume was found between two stages.There were no complications such as recurrent infection,hepatic and renal dysfunction,and deep venous thrombosis.Conclusion Treating infected TKA with AALCS can avoid spacer-related bone loss,preserve knee function between two stages,and eradicate infection effectively without significant complications.The early clinical results are inspiring.Radical debridement,individual application of systemic antibiotics,and reasonable juncture for the second revision are all key factors related to a successful outcome. Key words: Arthroplasty,replacement,knee; Prosthesis-related infections; Reoperation

Knee arthrodesis with a press-fit modular intramedullary nail without bone-on-bone fusion after an infected revision TKA

IntroductionKnee arthrodesis can be an effective treatment after an infected revision Total Knee Arthroplasty (TKA). The main hypothesis of this study is that a two-stage arthrodesis of the knee using a press-fit, modular intramedullary nail and antibiotic loaded cement, to fill the residual gap between the bone surfaces, prevents an excessive limb shortening, providing satisfactory clinical and functional results even without direct bone-on-bone fusion. Material and methodsThe study included 22 patients who underwent knee arthrodesis between 2004 and 2009 because of recurrent infection following revision-TKA (R-TKA). Clinical and functional evaluations were performed using the Visual Analogue Scale (VAS) and the Lequesne Algofunctional Score. A postoperative clinical and radiographical evaluation of the residual limb-length discrepancy was conducted by three independent observers. ResultsVAS and LAS results showed a significant improvement with respect to the preoperative condition. The mean leg length discrepancy was less than 1cm. There were three recurrent infections that needed further surgical treatment. DiscussionThis study demonstrated that reinfection after Revision of total knee Arthroplasty can be effectively treated with arthrodesis using a modular intramedullary nail, along with an antibiotic loaded cement spacer and that satisfactory results can be obtained without direct bone-on-bone fusion.

Preformed Antibiotic-Loaded Cement Spacers for Two-Stage Revision of Infected Total Hip Arthroplasty. Long-Term Results

Two-stage revision is the most widely accepted and performed intervention for chronically infected hip prosthesis and different interim spacers have been proposed. In recent years, antibiotic-loaded preformed spacers have become available on the market. The aim of this retrospective study was to assess the long-term results of two-stage revision with preformed spacers and uncemented hip prosthesis for the treatment of septic hip prosthesis. From 2000 to 2010, 183 consecutive patients underwent two-stage revision of septic hip prosthesis, with a same protocol, including preformed antibiotic-loaded cement spacer and a cementless modular hip revision prosthesis and four to six weeks antibiotic administration. Clinical and radiologic assessment at a minimum follow-up of two years was performed. At a minimum two years follow-up, 10 patients (5.4%) had had an infection recurrence, four (2.2%) an aseptic loosening and four more required partial revision of the modular components of the prosthesis, because of hip instability/dislocation; 21 patients died or were lost to follow-up. Considering all the reasons for revision, survivorship at eleven years was 93.9%. Harris Hip Score improved from 29.1 ± 14.6 pre-operatively to 41.1 ± 15.9 after spacer implant and 81.7 ± 17.6 after hip revision. The main complications after spacer implant included: spacer dislocation (16.4%), intra-operative femoral fractures (2.7%), and thromboembolism (2.1%). Complications after hip revision were: instability/dislocation (4,3%), intra-operative femoral fractures (1.6%), and thromboembolism (3.3%). Two-stage revision of septic hip prosthesis with preformed antibiotic-loaded spacers and cementless hip prosthesis provides satisfactory long-term results, with reduced complications.

Use of Positron Emission Tomography to Detect Infection Around Antibiotic-loaded Cement Spacers in Patients With High C-Reactive Protein Levels

In patients who have antibiotic-loaded cement hip spacers in the interim period, the correct diagnosis of infection eradication is the major determinant before reimplantation arthroplasty. Diagnosis is usually based on clinical findings and serum C-reactive protein (CRP) levels. However, diagnosis can be challenging when the clinical findings are normal but the CRP level is high. From March 2007 to January 2008, fluorodeoxy-glucose positron emission tomography (FDG-PET) was used to detect infection around antibiotic-loaded cement spacers in 13 patients (mean age, 60 years). Although patients' clinical conditions were deemed suitable for reimplantation, their serum CRP levels were persistently elevated (mean, 54 mg/L) an average of 120 days (range, 28-413 days) after the first-stage operation. Reimplantation total hip arthroplasty (THA) was subsequently performed in 7 patients based on the negative findings of FDG-PET. In 6 patients, FDG-PET was positive for infection. The persistence of infection was confirmed in 3 of these patients by another debridement surgery. Staged reimplantation THA was delayed in 1 patient who underwent repeat debridement and in 3 patients who were treated with extended periods of oral antibiotics. Of the 11 staged reimplantation THAs, only 1 reinfection was noted at an average follow-up of 48 months. The success rate of 91% suggests FDG-PET could help in the differential diagnosis of infection around cement spacers, especially in patients with normal clinical findings but elevated CRP levels.

Fungal Periprosthetic Hip and Knee Joint Infections: Clinical Experience With a 2-Stage Treatment Protocol

Fungal periprosthetic joint infections are a rare entity in orthopedic surgery, and there exist no guidelines according to which these infections can be successfully managed. Between 2004 and 2009, 7 patients with fungal periprosthetic joint infections (4 total hip arthroplasties and 3 total knee arthroplasties) have been treated with a 2-stage protocol and implantation of antibiotic-loaded cement spacers. Most of the infection was caused by Candida species. Systemic antifungal agents were administered for 6 weeks in 6 cases and 6 months in 1 case. The mean spacer implantation time was 12 weeks. At a mean follow-up of 28 months (5-70 months), no persistence of infection or reinfection could be observed. A 2-stage treatment protocol with implantation of an antibiotic-loaded cement spacer is an efficient option in the treatment of fungal periprosthetic infections.