For local antibiotic therapy gentamycin is in clinical use since many years, originally in the form of PMMA beads, later also in the form of resorbable collagen fleece. A prospective study comparing the efficacy of both application forms so far is missing. In a prospective study 108 patients with chronic sclerosing osteomyelitis were treated by a standardised operative debridement protocol. The debrided cavities were filled with 54 patients (group 1) were treated by local antibiotic beads (Septopal) and 54 patients (group 2) by local resorbable antibiotic fleece (Sulmycin). Both groups were comparable concerning age, location, duration of operation, type of osteomyelitis and predisposing factors. The mean follow-up was 6.1 years (range 3.8 – 9.3). Evaluation was done for the re-operation rate, CRP and ESR, white blood cells and local wound healing criteria. Twenty-six patients (44 per cent) underwent one or more revision operations because of persistent infection. In group I 67 per cent and in group II 20 per cent (p = 0.0001). No difference was noted for CRP (p = 0.46), ESR (p = 0.09), white blood cells (p = 0.24) and local wound healing criteria (p =0.34). After local gentamycin fleece application the early re-operation rate is significantly lower compared to gentamycin beads. After a treatment period of 3 month this difference disappears

Introduction: Purified plaster of Paris can be used as a resorbable carrier material for local antibiotic therapy. Clinical use already has been published with vancomycin and the aminoglycosides gentamycin and tobramycin. Calcium sulphate pellets with vancomycin can be manufactured during operation from Osteoset. ®. and vancomycin powder, whereas calcium sulphate with tobramycin is available as ready-to-use pellets under the brand name Osteoset T. ®. Results are promising. However, no data on systemic serum levels in humans have been published so far, despite well known toxicity issues of these antibiotics in systemic therapy. Methods: Following implantation of calcium sulphate with vancomycin or tobramycin, systemic serum levels of these antibiotics have been measured for up to 10 days, and prospectively gathered. Considering serum levels and renal function, pharmacokinetics have been estimated. Results: Between August 2006 and February 2008, calcium sulphate with vancomycin has been implanted in 15 patients, and with tobramycin in 12 patients. Whereas vancomycin levels remained very low, tobramycin levels close to the usually accepted trough levels could be observed at 24h post-operation. Conclusion: Vancomycin added to calcium sulphate has a safe systemic profile. On the contrary, significant serum levels of tobramycin can be measured more than 24h after implantation. Caution is mandatory when using this antibiotic, and explantation should be considered if levels too high are observed

Aim

Local antibiotics, delivered to the site of infection, achieve high tissue concentrations and are used as an adjunct to systemic therapy. Local gentamicin provides levels well above the minimum inhibitory concentration and may be sufficient on its own, however, the efficacy of single or combination local antibiotics has not been studied. This retrospective study evaluated the effect of combination aminoglycoside and vancomycin local antibiotic treatment compared to aminoglycoside alone in the surgical management of bone infection.

We reviewed 1085 consecutive compound limb fractures treated in 914 patients at the University of Louisville over a nine-year period. Of these fractures, 240 (group 1) received only systemic antibiotic prophylaxis and 845 (group 2) were managed by the supplementary local use of aminoglycoside-polymethylmethacrylate (PMMA) beads. There were no significant differences in age, gender, fracture type, fracture location or follow-up between the two groups. All had copious wound irrigation, meticulous debridement and skeletal stabilisation, but wound management and the use of local antibiotic depended on the surgeon's individual preference and there was no randomisation. In group 1 there was an overall infection rate of 12% as against 3.7% in group 2 (p < 0.001). Both acute infection and local osteomyelitis showed a decreased incidence in group 2, but this was statistically significant only in Gustilo type-IIIB and type-IIIC fractures for acute infection, and only in type-II and type-IIIB fractures for chronic osteomyelitis. Our review suggests that the adjuvant use of local antibiotic-laden PMMA beads may reduce the incidence of infection in severe compound fractures.

Aims

High-energy injuries can result in multiple complications, the most prevalent being infection. Vancomycin powder has been used with increasing frequency in orthopaedic trauma given its success in reducing infection following spine surgery. Additionally, large, traumatic injuries require wound coverage and management by dressings such as negative pressure wound therapy (NPWT). NPWT has been shown to decrease the ability of antibiotic cement beads to reduce infection, but its effect on antibiotic powder is not known. The goal of this study was to determine if NPWT reduces the efficacy of topically applied antibiotic powder.

Objective

A clinical investigation into a new bone void filler is giving first data on systemic and local exposure to the anti-infective substance after implantation.

Introduction. The management of open long bone fractures is well described and has been standardised through a number of well-established guidelines. However, there is no consensus regarding the application of local antibiotics into the open fracture site as a means of reducing infection rates. Materials & Methods. A systematic review and meta-analysis were undertaken as per PRISMA guidelines. PROSPERO Registration CRD42022323545. PubMed, EMBASE, Scopus and CENTRAL were the databases assessed. The Newcastle Ottawa Scale and the Rob 2 Tool were used to assess bias. A qualitative synthesis of all included studies and meta-analysis of suitable subgroups was undertaken. Results. In total, 12 studies (11 observational, 1 RCT) assessing 2431 open fractures were included for analysis. All compared the addition of a local antibiotic therapy to a standard treatment versus the standard treatment alone. The methods of delivery were vancomycin powder (4 papers), tobramycin polymethylmethacrylate beads (4 papers), gentamicin coated intramedullary (IM) nails (2 papers), gentamicin injections (1 paper) and antibiotic released IM core cement (1 paper). The addition of vancomycin powder did not decrease infection rates in comparison to intravenous antibiotics alone (OR 1.3, 95% CI (0.75 – 2.26)). Antibiotic coated IM Nails appear to have an association with lower infection rates than standard IM Nails. PMMA antibiotics have shown varied results in reducing infection rates depending on the individual studies. Conclusions. There are numerous methods available to deliver antibiotics locally to an open fracture site. Further high-quality research is required to provide a definitive conclusion on their efficacy irrespective of delivery method

Infections represent a devastating complication in orthopedic and traumatological surgery, with high rates of morbidity and mortality. An early intervention is essential, and it includes a radical surgical approach supported by targeted intravenous antimicrobial therapy. The availability of parenteral antibiotics at the site of infection is usually poor, so it is crucial to maximize local antibiotic concentration using local carriers. Our work aims to describe the uses of one of these systems, Stimulan®, for the management and prevention of infections at our Institution. Analysing the reported uses of Stimulan®, we identified two major groups: bone substitute and carrier material for local antibiotic therapy. The first group includes its application as a filler of dead spaces within bone or soft tissues resulting from traumatic events or previous surgery. The second group comprehends the use of Stimulan® for the treatment of osteomyelitis, post-traumatic septic events, periprosthetic joint infections, arthroplasty revision surgery, prevention in open fractures, surgery of the diabetic foot, oncological surgery and for all those patients susceptible to a high risk of infection. We used Stimulan® in several complex clinical situations: in PJIs, in DAPRI procedure and both during the first and the second stage of a 2-stage revision surgery; furthermore, we started to exploit this antibiotic carrier also in prophylaxis of surgical site infections, as it happens in open fractures, and when a surgical site remediation is required, like in osteomyelitis following ORIF. Stimulan® is an extremely versatile and polyhedric material, available in the form of beads or paste, and can be mixed to a very broad range of antibiotics to better adapt to different bacteria and their antibiograms, and to surgeon's needs. These properties make it a very useful adjuvant for the management of complex cases of infection, and for their prevention, as well

Aims. Bone and joint infections cause significant morbidity, often requiring combination medical and surgical treatment. The presence of foreign material reduces the number of organisms required to cause an infection. The aim of this study was to assess whether there was a difference in the species of organism identified on culture in osteomyelitis compared to prosthetic joint infection. Method. This was a retrospective observational cohort study of patients that had surgical intervention for prosthetic joint infection or osteomyelitis with positive microbial culture between 2019 and 2022. Data including patient demographics, site of injury, BACH score for osteomyelitis and JS-BACH score for prosthetic joint infection, organism classification and antibiotic resistance to vancomycin and gentamicin were extracted from the medical record. Logistic and multiple regressions were used to adjust for potential confounding variables. Results. A total of 445 patients were included in the study; 267 patients with osteomyelitis or fracture-related infection and 177 patients with prosthetic joint infection. The patients with prosthetic joint infection were older (Mean age 70 for PJI; IQR 60-77 vs 56 for OM/FRI; IQR 39-64), more likely to be female (55.6% vs 26.2%) and had a higher BMI and ASA compared to those with osteomyelitis. Symptom duration tended to be longer in osteomyelitis/FRI (p<0.001). Staphylococcus aureus was the most common pathogen isolated in both osteomyelitis (155/267 (58.1%)) and prosthetic joint infection (85/177 (48.9%), followed by other Gram negative pathogens with 77/267 (28.8%) in osteomyelitis and 48/177 (27.1%) in prosthetic joint infection. On multivariate analysis, there was no difference between the rate of Staphylococcus aureus infection between the two groups. The rate of polymicrobial infection was higher in patients with osteomyelitis (92/267 (34.5%)) compared to prosthetic joint infection (38/177 (23.7%), however after adjustment for confounders there was no difference, p = 0.842. There was no difference in the presence of gentamicin resistant organisms or vancomycin resistant Gram positive organisms in osteomyelitis compared to prosthetic joint infection. Conclusion. Causative pathogens are similar in these two common forms of bone and joint infection. There was no significant difference in the identification, presence of polymicrobial infection or gentamicin and vancomycin resistance in organisms isolated in osteomyelitis compared to prosthetic joint infection. This may have implications for empiric antibiotic choice and local antibiotic therapy in the management of bone and joint infection

Aims. The microbiological detection of microorganisms plays a crucial role in the diagnosis as well as in the targeted systemic and local antibiotic therapy of periprosthetic infections (PJI). Despite extensive efforts to improve the sensitivity of current culture methods, the rate of culture-negative infections is approximately 10–20% of all PJI. This study investigates an preanalytical algorithm (culture collection and direct processing in the OR) to potentially increasing culture yield in patients with PJI. Methods. Patients undergoing staged revision arthroplasty for PJI in our hospital between October 2021 and 2022 were included in this prospective pilot study. Intraoperatively twenty tissue samples were collected and distributed among 4 groups. Tissue samples were prepared according to standard without medium and in thioglycolate medium at 3 different temperatures (room temperature, 4°C, 37° for 24h before transport to microbiology) directly in the OR. The removed implants were sonicated. Cultures were investigated on days 1, 3, 7, 12, 14 for possible growth. All grown organism, the number of positive samples and the time to positivity were recorded and compared. Results. 71 patients were included (age, gender). Compared to the standard procedure the thioglycolate broth at 37°C was significantly more often culture-negative (p=0.031). No significant differences in the frequency of culture-negative samples were detected in the other groups. 8.4% (6/71) patients were culture negative in the standard culture but positive in the thioglycolate samples. In contrast, 7% (5/71) were culture negative in the thioglycolate samples but had bacterial detection in the standard approach. In 4.7% (3/63) of the patients, only the sonication showed growth, whereas 25.4% (16/63) had no growth in sonication fluid but in one of the cultures. For S. caprae, there was a significantly different distribution (p=0.026) with more frequent detection in the group with thioglycolate at 37°C. The standard procedure (p=0.005) and sonication (p=0.023) showed a shorter time to positivity of the culture compared to the thioglycolate approach at 4°C. Conclusions. No general differences could be shown between the standard preparation and the thioglycolate preparation; in particular, storage at different temperatures does not seem to result in any difference. For individual cases (8% in this study), bacterial growth was detected in the thioglycolate group that would have been culture-negative otherwise. There might be organism dependent differences in growth in different media

Introduction. Since the expanded war in Ukraine in 2022, explosives, mines, debris, blast waves, and other factors have predominantly caused injuries during artillery or rocket attacks. These injuries, such as those from shelling shrapnel, involve high-energy penetrating agents, resulting in extensive necrosis and notable characteristics like soft tissue defects and multiple fragmentary fractures with bone tissue defects and a high rate of infection complications caused by multi resistant gram-negative (MRGN) pathogens. Material and Methods. We conducted a prospective study at our center between March 2022 and December 2023. Out of the 56 patients from Ukraine, 21 met the inclusion criteria who had severe war injuries were included in the study. Each of these patients presented with multiple injuries to both bones and soft tissues, having initially undergone treatment in Ukraine involving multiple surgeries. The diagnosis of infection was established based on the EBJIS criteria. Prior to our treatment patients had undergone multiple revision surgeries, including debridement, biopsies, implant and fixator replacement. Additionally, soft tissue management required previously VAC therapy and flap reconstruction for successful treatment. Results. All 21 infections manifested as bone infections (11; 52%), followed by implant-associated infections (5; 24%), soft tissue infections (4; 19%), and septic arthritis (1; 5%). In all patients, the infection was polymicrobial, caused by 3- and 4-MRGN pathogens, as Klebsiella pneumonia 4MRGN, Proteus mirabilis 4MRGN, Enterobacter cloacae 4MRGN etc. Upon admission, all patients carried a diagnosis and exhibited signs indicative of chronic infection. 19 (90.5%) patients required complex antibiotic regimens combined with multiple wound revisions and debridements, changes of fixators and combination of systemic and local antibiotic therapy. In 6 patients (28%) high dosages of local antibiotics such as gentamycin, vancomycin and meropenem were incorporated into a carrier of bio-absorbable calcium sulfate, calcium sulfate/hydroxyapatite which were introduced into the hip joint, femoral canal or bone defect for dead space management during the surgery. When local antibiotics were administered at intervals, the microbiology results at implantation showed negative results. 2 (9%) patients had new infections (different site, different pathogens), 1 (4.8%) is still under the treatment. In 17 (81%) patients infection complications were treated successfully with no recurrence of infection. Conclusion. War injuries result in complex bone and soft-tissue infections caused by 3-, 4-MRGN pathogens. Addressing this challenge necessitates multidisciplinary approach with multiple, thorough surgical debridements, effective local, and systemic antimicrobial therapy. As for the outlook we can see potential in local antibiotic carriers

Aim. Skeletal tuberculosis (TB) accounts for up to one third of cases of extra-pulmonary TB but comprises a minority of osteoarticular infection in areas with low TB incidence. Consequently, unexpected cases may receive surgical management targeted at non-tuberculous orthopaedic infections. This study reviewed treatment and outcomes of non-spinal osteoarticular TB to assess outcomes from modern surgical techniques. Method. All patients with a diagnosis of non-spinal osteoarticular TB between 2009–2017 from one tertiary referral centre were included. Retrospective review of surgical intervention, antibiotic treatment and outcome was conducted. Results. Fourteen patients with an average age of 48 (range 20–77) were identified; all were HIV-negative. Articular infections affected 7 patients, including one prosthetic joint infection. Osteomyelitis affecting the carpus, femur, tibia, olecranon and metatarsals was diagnosed in the remaining patients. Only 4 patients had radiological findings consistent with prior pulmonary TB, and only 3 had a history of prior TB or TB exposure. In 2 cases, symptom exacerbation was associated with local steroid injection. Diagnostic biopsy was employed in 5 cases, of whom 4 proceeded to medical management. Diagnosis was made following positive culture in 86% of cases; all TB isolates were fully sensitive. 71% of cases underwent surgical treatment according to best practice for biofilm-forming infection, including excision of osteomyelitis with local antibiotic therapy for three patients, and first-stage excision with spacer implantation for four patients. Quadruple therapy for an average of 8.5 months, range 6–12 months, was administered. Patients were followed up for a mean of 15.2 months. Half of the patients treated with surgery reported ongoing pain at 3 months and 4 patients underwent further surgery for persistent signs of infection (2 for probable persistent TB, 2 for bacterial super-infection). Conclusions. The role of surgical debridement in management of osteoarticular TB is unclear. In patients with a previous history of TB exposure a pre-operative diagnosis of TB could prevent unnecessary surgery and therefore prevent associated post-operative complications including bacterial super-infection and pain. Pre-op biopsy should therefore be considered in all patients with a history of TB exposure

There has been a significant increase in the demand of polymeric scaffolds with promising affects in bone regeneration. However, inflammation is still a problem in transplantations to overcome with local antibiotic therapy. In this study, it is aimed to develop a functional POSS nanocage reinforced chitosan scaffold (CS/POSS) coated with drug loaded chitosan composite nanospheres to provide a controlled antibianyiotic delivery at the defect site. Gentamicin and vancomycin were selected as model antibiotic drugs. Drug loaded nanospheres were fabricated with electrospray method and characterized in terms of morphology, hydrodynamic size, surface charge, FT-IR, in vitro drug release, antimicrobial activity and cytotoxicity. CS/POSS scaffolds were fabricated via lyophilisation and characterized with mechanic, swelling test, SEM and micro CT analyses. Positively charged nanospheres with uniform morphology were obtained. High drug encapsulation efficiency (80–95%) and sustained release profile up to 25 days were achieved with a cumulative release of 80–90%. In addition, the release media of the nanospheres (in 6 hours, 24 hours and 25 days of incubation period) showed a strong antimicrobial activity against S.aureus and E.coli, and did not show any cytotoxic effect to 3T3 and SaOS-2 cell lines. CS/POSS scaffolds were obtained with high porosity (89%) and 223.3±55.2μm average pore size. POSS reinforcement increased the compression modulus from 755.7 to 846.1Pa for 10 % POSS addition. In vitro studies of nanosphere coated bilayer scaffolds have showed high cell viability. Besides ALP activity results showed that POSS incorporation significantly increased the ALP activity of Saos-2 cells cultured on the scaffold. In conclusion, these composites can be considered as a potential candidate in view of its enhanced physico-chemical properties as well as biological activities for infection preventive bone tissue engineering applications

Several risk factors can and should be addressed during first stage or spacer implantation surgery in order to minimize complications. Technical aspects as well as practical tips and pearls to overcome common nuisances such as spacer instability or femoral and acetabular bone loss will be discussed and shown with pictures. Total joint arthroplasty (TJA) is one of the most successful procedures in orthopaedics and excellent results are expected in virtually all cases. Periprosthetic joint infection (PJI) though unusual, is one of the most frequent and challenging complications after TJA. It is the third most common cause of revision in total hip replacement, responsible for up to 15% of all cases. In the past few years several improvements have been made in the management of an infected total hip prosthesis. Nevertheless it remains a challenging problem for the orthopaedic surgeon. Although numerous studies report favourable outcomes after one-stage revision surgery, two-stage has traditionally been considered as the gold standard for management of chronic infection. Two-stage exchange consists of debridement, resection of infected implants and usually temporary placement of an antibiotic-impregnated cement spacer before reimplantation of a new prosthesis. Spacers can be classified as static or articulating. The goals of using an articulating antibiotic loaded cement spacer are two-fold: to enhance the clearance of infection by local antibiotic therapy and dead-space management while maintaining joint function during treatment thus improving the functional outcome at reimplantation. Still, hip spacer implantation is not innocuous and there are several possible complications. Going forward, one must consider not just eradicating infection but also the importance of restoring function. In this regard using a mobile spacer adds an element of physiologic motion that both increases patient comfort between stages and facilitates re-implantation surgery. Conversely, mechanical complications are one of the major consequences of this preference. Be that as it may there are ways to minimize these problems. It is the surgeon responsibility to optimize mechanical circumstances as much as possible. I would like to thank Dr. Ricardo Sousa for his help with this work

Gentamicin incorporated in beads of polymethylmethacrylate has been shown capable of being released over a period of several months in concentrations sufficiently high to control most pathogens. The therapeutic efficacy of such beads has been demonstrated in a model of osteomyelitis of the femur in the dog. Good tolerance has been shown, both in the animal model and in tissue cultures. In forty-one patients with infection of either bone or soft tissue, mainly of the lower limb, the findings were similar. The concentrations in serum and urine were low, which excludes side-effects. The insertion of gentamicin-PMMA beads may prove to be a valuable new form of local antibiotic therapy

Introduction. Calcium sulphate is a resorbable void filler that can be used for local antibiotic delivery. Results from clinical studies on chronic osteomyelitis thus treated with local vancomycin have already been published. Despite significant exposure to this drug, there are no pharmacokinetic studies published so far. Based on observations in our patients, a model predicting vancomycin serum and wound fluid levels and toxicity potential is presented. Methods. Following implantation of Osteoset® added with vancomycin, serum and wound fluid concentrations of this antibiotic have been monitored systematically. The pharmacokinetic analysis was performed using a non-linear mixed-effects model based on a one-compartment model with first-degree absorption. Results. Data from 43 patients treated between October 2006 and August 2010 were analysed. Serum concentrations remained far below the usually accepted trough levels of 10 mg/L, and were still acceptable in two cases of post-operative renal failure. Wound fluid concentrations around 1,000 mg/l were observed for the first 7–10 days, and remained above usual minimal inhibitory concentrations for approximately a month. Discussion and Conclusion. This is the first pharmacokinetic exploration of calcium sulphate added with vancomycin for local antibiotic therapy. The systemic exposure to vancomycin is low and appears safe even after implantation of up to 6 g vancomycin, except in case of markedly impaired renal function. Wound fluid concentrations of vancomycin appear extremely interesting for further studies

Implantation of antibiotic-loaded beads is accepted as an efficient option for local antibiotic therapy in orthopedic-related infections. However, recent reports have emphasized the bacteria growth persistence on antibiotic-impregnated bone cement. Hence, the aim of this study was to elaborate if bacterial adherence and growth could be determined on explanted gentamicin- and gentamicin-vancomycin-loaded beads after infection eradication. 18 chains of antibiotic-loaded beads (11 gentamicin-, 7 gentamicin-vancomycin-loaded) were examined. Indications for primary beads implantation included postoperative infections after total hip or knee arthroplasty, rotator cuff reconstruction, chronic foot osteomyelitis, anterior cruciate ligament reconstruction and dorsal spondylodesis. Among the isolated organisms, Staphylococcus epidermidis, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) were the most frequent ones. In 4 cases (3 × S. epidermidis, 1 × MRSA) bacteria growth persistence could be determined on the beads. S. epidermidis-strains persisted only on gentamicin-loaded beads, MRSA could grow on gentamicin-vancomycin-impregnated cement. In one case, the emergence of a gentamicin-resistant S. epidermidis-strain could be observed despite preoperative susceptibility. Bacteria growth persistence on bone cement is a hazardous problem in the orthopedic surgery and should therefore be born in mind. Adherence to cement can lead to emergence of bacteria resistance despite preoperative antibiotic susceptibility and might result in clinical recurrence of infection

Some different biodegradable vehicles have been tried in vitro and in vivo as possible methods of local antibiotic therapy. The aim of this study is to evaluate the effectiveness of collagen-gentamicine (Collatamp. ®. ) to eradicate bacterial colonisation of different biomaterials used in orthopaedic surgery in an in vitro study. Three samples of similar shapes and dimensions of 4 different materials: stainless steel screw, titanium screw, titanium canulated screw and a cylinder of polyethylene were used. Three different solutions of 49 cc of thioglicolate plus 1cc of solution of methicillin-susceptible and methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis (MacFarland: 3) were prepared. Each solution received one sample of each material so that every material be tested in all 3 preparations. After incubation during one week and confirmation of bacterial colonisation of each sample by swabbing cultures, all of them were introduced in an individual receptacle containing 50 cc of thioglicolate and a piece of 5x5 cm of collagen-gentamicine (corresponding to 650 mg/ml of gentamicine). After incubation we analysed results by new swabbing cultures of all samples. All samples were highly contaminated with different bacteria before introducing them in thioglicolate with the piece of collagen-gentamicine. After one week all samples were free of bacteria. This in vitro study demonstrates the effectiveness of collagen-gentamicine in order to eliminate colonisation of different biomaterials used in orthopaedic surgery by most frequent bacteria

Background and purpose: Commercial gentamicin-loaded bone cement beads (Septopal. ®. ) constitute an effective delivery system for local antibiotic therapy. However, these beads are not commercially available in all parts of the world, and are too expensive for common use in others. Therefore, orthopedic surgeons worldwide make antibiotic-loaded beads themselves. However, these beads are usually not as effective as the commercial beads because of inadequate release kinetics. The aim of this study was to develop a simple, cheap and effective formulation to prepare gentamicin-loaded beads with release properties and antibacterial efficacy similar to the ones of commercially available beads. Methods: Acrylic beads were first prepared with variable monomer contents: 500 μl/g polymer (100%), 375 μl/g polymer (75%), and 250 μl/g polymer (50%) to increase gentamicin release through the creation of a less dense polymer matrix. After optimal monomer content was defined, different gel-forming polymeric fillers were added to enhance the permeation of fluids into the beads. Polyvinylpyrrolidone (PVP) 17 was selected as a suitable filler, its concentration was varied and the antibiotic release and antibacterial efficacy of the final beads were compared with the ones of Septopal. ®. beads. Results: Gentamicin release rate and extend of release from beads prepared with 50% monomer increased upon increasing the PVP 17 content in the beads. Beads with 15 w/w% PVP 17 released 87% of their antibiotic content within 336 h. Importantly, this is significantly more than the gentamicin-release from Septopal. ®. beads, that appeared confined to only 59% within 336 h. In addition, acrylic beads with 15 w/w% PVP 17 reduced bacterial growth up to 93%, which is a similar reduction as achieved with Septopal. ®. . Interpretation: A simple, cheap and effective formulation and preparation process has been described for hand-made gentamicin-releasing acrylic beads, with release kinetics and antibacterial efficacy similar to the ones of commercially available Septopal. ®. beads

Two-stage revision is the most widely accepted and performed intervention for chronically infected joint prosthesis. The choice of this option relies on the following considerations:. higher antibiotic concentrations may be used in the spacers, compared to the cement used for prosthetic fixation in a single-stage procedure, since high dose antibiotic-loaded cement may be too fragile for long term prosthesis fixation (Bucholz, 1986);. the frequent occurrence of bone loss and the smooth cortical bone surface, encountered at revision may prevent effective cementing;. two-stage revision allows the use of uncemented modular stems, useful for intra-operatively balancing legs’ length, offset and muscular tension;. distal fixation allows to overcome proximal frequent bone loss;. bone grafts, eventually plus growth factors, may be safely added;. a second debridment may enhance the possibility of eradicating the infection;. there is a large and growing international literature evidence in support to this option. Two-stage reimplantation using an articulated interval spacer of antibiotic-impregnated bone-cement has been previously investigated and proved as an effective Method:. to adequately fill the void created by the implant removal,. to prevent limb shortening and soft-tissue contracture,. to allow a better function,. to provide local antibiotic therapy,. to eradicate infection,. to facilitate reimplantation. However a considerable variation in the form and function of interval spacers exists. A spacer may in fact be commercially made, or it may be custom-made in the operating room. It may be made entirely of polymethylmethacrylate cement, or it may be a cement-coated metal composite. Favorable results have been reported with each of these types of spacers. Preformed antibiotic-loaded spacers (InterSpace® Hip and InterSpace® Knee, Tecres SpA, Verona, Italy – Hexactech Inc. Gainesville, Florida) offer:. known mechanical resistance;. predictable antibiotic release;. reduced surgical time;. joint function preservation and partial weight bearing;. standardized technique. In particular, as to concern the hip, their most peculiar feature is their availability in short and long stem shapes, that allows to overcome frequent proximal femoral bone defects. Acceptable costs (< 5% of the total costs for a two-stage procedure)