Novel method for delayed primary closure and incisional hernia prevention in open abdomen: COmbined and MOdified Definitive Abdominal wall closure (COMODA).

BACKGROUND: Intended open abdomen is an option in cases of trauma and non-trauma patients. Nevertheless, after primary closure, incisional hernia rate is high. We describe a novel method, called COmbined and MOdified Definitive Abdominal closure (COMODA), a delayed primary closure which prevents incisional hernia. METHODS: A negative pressure wound therapy system is combined with a condensed polytetrafluoroethylene (cPTFE) mesh. TRIAL REGISTRATION: ISRCTN72678033. RESULTS: Ten male patients with a median age of 68.8 (43-87) years were included. Primary closure rate was 100% per protocol. The median number of procedures per patient was 5.7 (5-9). Primary closure was obtained in 20.8 (10-32) days and median hospital stay was 36.3 (18-52) days. Only one patient developed incisional hernia during a median follow-up of 27 (8-60) months. CONCLUSION: COMODA method allows for a high rate of delayed primary closure. It is safe and decreases the risk for developing an incisional hernia. However, a large number of patients are needed to support this conclusion.

Rechargeable anticandidal denture material with sustained release in saliva.

OBJECTIVE: Candida-induced denture stomatitis is a common debilitating problem among denture wearers. Previously, we described the fabrication of a new denture material that released antifungal drugs when immersed in phosphate buffered saline. Here, we use more clinically relevant immersion conditions (human saliva; 37°C) and measure miconazole release and bioactivity. MATERIALS AND METHODS: Disks were prepared by grafting PNVP [poly(N-vinyl-2-pyrrolidinone)] onto PMMA [poly(methylmethacrylate)] using plasma initiation (PMMA-g-PNVP) and then loaded with miconazole. Drug-loaded disks were immersed in 10-100% human saliva (1-30 days). Miconazole release was measured and then tested for bioactivity vs miconazole-sensitive and miconazole-resistant Candida isolates. RESULTS: HPLC was used to quantify miconazole levels in saliva. Miconazole-loaded disks released antifungal drug for up to 30 days. Higher drug release was found with higher concentrations of saliva, and, interestingly, miconazole solubility was increased with higher saliva concentrations. The released miconazole retained its anticandidal activity. After immersion, the residual miconazole could be quenched and the disks recharged. Freshly recharged disks displayed the same release kinetics and bioactivity as the original disks. Quenched disks could also be charged with chlorhexidine that displayed anticandidal activity. CONCLUSIONS: These results suggest that PMMA-g-PNVP is a promising new denture material for long-term management of denture stomatitis.

UV-curable gel formulations: Potential drug carriers for the topical treatment of nail diseases.

Nail diseases are common, cause significant distress and treatments are far from successful. Our aim was to investigate the potential of UV-curable gels - currently used as cosmetics - as topical drug carriers for their treatment. These formulations have a long residence on the nail, which is expected to increase patient compliance and the success of topical therapy. The gels are composed of the diurethane dimethacrylate, ethyl methacrylate, 2-hydroxy-2-methylpropiophenone, an antifungal drug (amorolfine HCl or terbinafine HCl) and an organic liquid (ethanol or NMP) as drug solvent. Following its application to a substrate and exposure to a UVA lamp for 2 min, the gel polymerises and forms a smooth, glossy and amorphous film, with negligible levels of residual monomers. No drug-polymer interactions were found and drug loading did not affect the film's properties, such as thickness, crystallinity and transition temperatures. In contrast, the organic solvent did influence the film's properties; NMP-containing films had lower glass transition temperatures, adhesion and water resistance than ethanol-based ones. Water-resistance being a desired property, ethanol-based formulations were investigated further for stability, drug release and ungual permeation. The films were stable under accelerated stability testing conditions. Compared to terbinafine, amorolfine was released to a greater extent, had a higher ungual flux, but a lower concentration in the nailplate. However, both drugs were present at considerably high levels in the nail when their MICs are taken into account. We thus conclude that UV-curable gels are promising candidates as topical nail medicines.

Antibiotic-laden PMMA bead chains for the prevention of infection in compound fractures: current state of the art.

Antibiotic-laden PMMA bead chains are a valuable method of local antibiotic treatment in the prevention of infection in open fractures. When used in this setting, they provide high concentrations of broad-spectrum antibiotics to the area of the highest risk which may not be well perfused or reached by systemic antibiotics, while also eliminating dead space. In this article, the historical and current state of antibiotic-laden bead chains is discussed. The literature provides evidence that antibiotic-laden bead chains are a useful adjuvant with systemic antibiotics in the prevention of infection in open fractures. These bead chains can be sterilely prepared in the operating room or manufactured, and they maintain their elution and antimicrobial properties for a considerable time period. The bead chains also allow a high local concentration of antibiotics without risk of systemic toxicity or fear of clinically significant growth or persistence of bacteria on the beads. Bead chains are a practical method of local antibiotic therapy when the wounds can be closed.

Ocular delivery of flurbiprofen based on Eudragit(®) E-flurbiprofen complex dispersed in aqueous solution: preparation, characterization, in vitro corneal penetration, and ocular irritation.

A novel ophthalmic formulation based on the ionic complexation between Eudragit E 100 (EU) and flurbiprofen (FB) is proposed. The selected complex composition, named EU-FBH50 Cl50 , had the basic groups of EU completely neutralized with equal molar amounts of FB and HCl. This complex, obtained in the solid state, exhibited a high aqueous compatibility producing a colloidal dispersion with a high positive electrokinetic potential, in which more than 99% of FB was ionically condensed with EU. In bicompartimental Franz cells, FB diffusion from the complex was very slow. However, dispersion in 0.9% NaCl increased the FB release through an ionic exchange, providing an optimal constant rate of delivery. Corneal FB permeation from 0.1% EU-FBH50 -Cl50 dispersed in 0.9% NaCl solution was substantially more effective compared with 0.1% FB solution, EU-FBH50 -Cl50 (Dex), or Tolerane(®) (a marketed formulation). This complex formulation was shown to be innocuous for rabbit ocular tissues because no irritant effects were evidenced.

Good results in postoperative and hematogenous deep infections of 89 stable total hip and knee replacements with retention of prosthesis and local antibiotics.

BACKGROUND: Deep postoperative and hematogenous prosthesis infections may be treated with retention of the prosthesis, if the prosthesis is stable. How long the infection may be present to preclude a good result is unclear. PATIENTS AND METHODS: We retrospectively studied 89 deep-infected stable prostheses from 69 total hip replacements and 20 total knee replacements. There were 83 early or delayed postoperative infections and 6 hematogenous. In the postoperative infections, treatment had started 12 days to 2 years after implantation. In the hematogenous infections, symptoms had been present for 6 to 9 days. The patients had been treated with debridement, prosthesis retention, systemic antibiotics, and local antibiotics: gentamicin-PMMA beads or gentamicin collagen fleeces. The minimum follow-up time was 1.5 years. We investigated how the result of the treatment had been influenced by the length of the period the infection was present, and by other variables such as host characteristics, infection stage, and type of bacteria. RESULTS: In postoperative infections, the risk of failure increased with a longer postoperative interval: from 0.2 (95% CI: 0.1-0.3) if the treatment had started ≥ 4 weeks postoperatively to 0.5 (CI: 0.2-0.8) if it had started at ≥ 8 weeks. The relative risk for success was 0.6 (CI: 0.3-0.95) if the treatment had started ≥ 8 weeks. In the hematogenous group, 5 of 6 infections had been treated successfully. INTERPRETATION: A longer delay before the start of the treatment caused an increased failure rate, but this must be weighed against the advantage of keeping the prosthesis. We consider a failure rate of < 50% to be acceptable, and we therefore advocate keeping the prosthesis for up to 8 weeks postoperatively, and in hematogenous infections with a short duration of symptoms.

Evaluation of in vitro dissolution and in vivo oral absorption of dutasteride-loaded eudragit E nanoparticles.

The present study sought to evaluate the pharmacokinetics of dutasteride-loaded Eudragit E nanoparticle in rats. In addition, the study investigated the effect of increasing drug load on the in vitro solubility and dissolution behavior of dutasteride together with its in vivo oral absorption characteristics. The suspension of dutasteride-loaded Eudragit E nanoparticles prepared by the nanoprecipitation method showed blue opalescence and the particles were uniform in appearance. The entrapment efficiency and the mean particle size of these nanoparticles were in the range of 98.1-99.3% and 120.5-128.4 nm, respectively, and no significant difference in these parameters was observed between the nanoparticles in the sample. Eudragit E nanoparticles containing a drug load of 5% showed an increase in bioavailability by 550% as compared to dutasteride suspension. This finding is attributable to enhanced solubility and dissolution of dutasteride when formulated as nanoparticles. Furthermore, the oral absorption of dutasteride in rats increased as a function of the extent of supersaturation of dutasteride in Eudragit E nanoparticles. Therefore, the preliminary results from our study suggest that dutasteride-loaded Eudragit E nanoparticles may have significant potential for clinical application.

Gentamicin serum concentrations in patients with gentamicin-PMMA beads for infected hip joints: a prospective observational cohort study.

BACKGROUND: Gentamicin-polymethylmethacrylate (PMMA) beads release gentamicin gradually, and high concentrations develop only locally. It is unclear how frequent and in which patients gentamicin serum concentrations are measurable and possibly lead to toxicity. The aim of this study was to investigate the measurability of gentamicin serum concentrations after the implantation of gentamicin-PMMA beads and to assess the nephrotoxicity of these beads. METHODS: In this observational cohort study, gentamicin and creatinine concentrations were measured in 34 serum samples of 23 patients with implanted gentamicin-PMMA beads for infected hip joints with our regular immunoassay (lower limit of quantitation 0.4 mg/L). Samples were also analyzed with an adjusted immunoassay with a lower limit of quantitation of 0.05 mg/L. RESULTS: Gentamicin serum concentrations were >0.4 mg/L in 9 of 34 (26%) of all the samples measured (both after the first implantation and change of beads) and in 5 of 23 patients (22%) after the first implantation of gentamicin-PMMA beads. Gentamicin serum concentrations were >0.05 mg/L in 31 samples (91%). Nephrotoxicity (defined as increase in serum creatinine >44 µmole/L and/or a relative increase >25%) occurred more frequently in patients with measurable gentamicin serum concentrations than in those without measurable gentamicin serum levels (57% versus 43%, P = 0.02). Both nephrotoxicity and gentamicin serum concentration could not be associated with the number of implanted gentamicin-PMMA beads. CONCLUSIONS: Gentamicin serum concentrations >0.4 mg/L can be measured after the implantation of gentamicin-PMMA beads in certain patients with infected hip joints. Furthermore, elevated (>0.4 mg/L) gentamicin serum concentrations are associated with nephrotoxicity in patients with gentamicin-PMMA beads for infected hip joints.

Improved immune responses in mice using the novel chitosan adjuvant ViscoGel, with a Haemophilus influenzae type b glycoconjugate vaccine.

An immune response to an antigen is more efficiently induced in combination with an adjuvant. Chitosan has due to documented immunostimulatory characteristics been proposed as an adjuvant candidate. However, a disadvantage with chitosan is its poor solubility at physiological pH. We have circumvented this obstacle by using a soluble type of chitosan (Viscosan), with a degree of deacetylation (DD) of 50% and a random distribution of acetyl groups. A hydrogel, ViscoGel, was made from Viscosan which was further mechanically processed into gel particles of predefined size. The first cells to infiltrate ViscoGel in mice, were identified mainly as neutrophils, detected already after 4 h. ViscoGel's impact on the immune response in mice together with a commercial vaccine against Haemophilus influenzae type b (Act-HIB) was then studied. Mixing Act-HIB with ViscoGel, induced significantly enhanced IgG1 and IgG2a titers in serum (p<0.05). We could reduce the antigen dose ten-fold in combination with ViscoGel and still obtain antibody titers similar to 2 µg Act-HIB administered alone. In addition, the Act-HIB specific cellular response was stronger in mice vaccinated together with ViscoGel (p<0.05). The cytokine response after vaccination with Act-Hib together with ViscoGel was of a mixed type. We found elevated levels of the Th1 associated cytokine INF-γ, the Th2-cytokine IL-4, the proinflammatory IL-6 and IL-17A, and the regulatory cytokine IL-10. Similar effects were seen when the adjuvant was administered either subcutaneously or intramuscularly. Taken together, using vaccination against H. influenzae type b as a model, we here show proof of concept for the novel vaccine adjuvant candidate, ViscoGel.

Characterisation and toxicological behaviour of Basic Methacrylate Copolymer for GRAS evaluation.

Basic Methacrylate Copolymer is a fully polymerised cationic copolymer with taste-masking and moisture protection properties. It is used as a pharmaceutical excipient and has potential use as a glazing/coating agent to solid food supplements. This article describes available information on the safety of the substance. Oral administration of radiolabelled copolymer to rats showed the major route of excretion to be via the faeces. Minor absorption may occur at <0.02%. Safety studies revealed no adverse toxicity following repeated administration at up to 2000 mg/kg/day in a sub-chronic study in the rat or 750 mg/kg/day in a sub-acute study in the dog. No reproductive toxicity occurred at up to 1000 mg/kg/day in the rat. The substance shows no evidence of genotoxicity, has low acute toxicity and no irritation or sensitisation potential. As per the FDA approach an ADI of 20 mg/kg bw can be concluded. Daily exposure from use as a food additive is estimated as up to 11.7 mg/kg bw in adults and 13.3 mg/kg bw in children. In view of the high molecular weight of the substance, its lack of absorption and its low toxicity profile, the ADI is deemed adequate.

'To bead or not to bead?' Treatment of osteomyelitis and prosthetic joint-associated infections with gentamicin bead chains.

Gentamicin-containing polymethylmethacrylate (PMMA) beads are frequently used to prevent and treat orthopaedic infections. The beads are typically inserted to fill anatomical defects secondary to surgical debridement. Local gentamicin use results in low serum levels whilst achieving high concentrations at the site of infection. However, a systematic review of the available literature showed that, despite these theoretical advantages, no prospective study has thus far proven gentamicin-containing PMMA beads to be effective in treating orthopaedic infections. Available studies are based on small patient numbers and do not show significantly better results when local and parenteral antibiotics are combined compared with systemic therapy alone. These poor results may be explained partially by reduced aminoglycoside efficacy when biofilms or gentamicin-resistant bacteria are present. Moreover, little is known regarding the potential side effects of gentamicin-containing beads. In this paper, the pros and cons regarding the use of gentamicin-containing PMMA beads are discussed. It is concluded that more well-executed, prospective studies are needed to settle the discussion on the use of gentamicin-containing beads in the treatment of orthopaedic infections.

[Arthritis and osteitis at the hand]. / Arthritis und Osteitis an der Hand.

Septic arthritis and osteitis at the hand are associated with a high morbidity. Trauma is the major cause for these infections. In the majority of cases the fingers are involved. Causative microorganisms are predominantly Staphylococcus aureus and Streptococcus pyogenes. In addition, an increasing number of Gram-negative bacteria have been found in hand infections. As differential diagnosis, tumours and non-septic arthritis must be considered. Treatment includes surgical debridement, immobilisation and functional rehabilitation. Crucial for the surgical strategy are the virulence of the pathogens, the resistance of the patient and the location of the infection. If functional recovery cannot be expected, salvage procedures like arthrodeses and resection arthroplasties are sometimes required. Surgical treatment is sufficient in septic arthritis and osteomyelitis of the hand. However, to avoid permanent disability, rapid diagnosis and therapy are essential. This review describes our treatment concepts in septic arthritis and osteomyelitis at the hand.

Effect of antifungal gels incorporated into a tissue conditioning material on the growth of Candida albicans.

OBJECTIVE: The aim of this study was to examine the effectiveness of antifungal gels incorporated into a tissue conditioner which inhibits the growth of Candida albicans in vitro. BACKGROUND: The release of drugs from relining materials has been demonstrated earlier. However, the incorporation of antifungal agents in gel form has not yet been studied. MATERIALS AND METHODS: Visco-gel(®) tissue conditioner was prepared with chlorhexidine digluconate and miconazole in gel form in a concentration of 5, 10, 15, 20 and 25% by volume. Sample discs were prepared and placed on Sabouraud Dextrose Agar (SDA) plates which had been previously inoculated with C. albicans, and incubated aerobically at 37 °C. To investigate antifungal activity over time, Visco-gel discs containing 20%v/v miconazole were prepared and immersed in water for different time periods before being placed on SDA plates inoculated with C. albicans. RESULTS: Chlorhexidine digluconate gel added to tissue conditioner had no inhibition effect on the growth of C. albicans. Incorporation of miconazole gave a dose-related inhibitory effect on candidal growth. Immersion of the discs in water showed an inverse relationship between time of immersion and degree of inhibition. CONCLUSION: Miconazole added in gel form to Visco-gel(®) had an inhibitory effect on the growth of C. albicans in vitro.

Concepts for increasing gentamicin release from handmade bone cement beads.

BACKGROUND AND PURPOSE: Commercial gentamicin-loaded bone cement beads (Septopal) constitute an effective delivery system for local antibiotic therapy. These beads are not available in all parts of the world, and are too expensive for frequent use in others. Thus, 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. Our purpose was to develop a simple, cheap, and effective formulation to prepare gentamicin-loaded beads with release properties and antibacterial efficacy similar to the commercially ones. METHODS: Acrylic beads were prepared with variable monomer content: 100% (500 microL/g polymer), 75%, and 50% to increase gentamicin release through creation of a less dense polymer matrix. Using the optimal monomer content, 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 these beads were compared with the corresponding properties of the commercial ones. RESULTS: Gentamicin release rate and the extent of release from beads prepared with 50% monomer increased when the PVP17 content was increased. Beads with 15 w/w% PVP17 released 87% of their antibiotic content. This is substantially more than the gentamicin release from Septopal beads (59%). Acrylic beads with 15 w/w% PVP17 reduced bacterial growth by up to 93%, which is similar to the antibacterial properties of the commercial ones. INTERPRETATION: A simple, cheap, and effective formulation and preparation process has been described for hand-made gentamicin-releasing acrylic beads, with better release kinetics and with antibacterial efficacy similar to that of the commercial ones.

Knee arthodesis using a modular customized intramedullary nail.

INTRODUCTION: Arthrodesis of the knee, particularly in infectious situations, can be achieved using either an external fixator or an intramedullary device. The objective of this study is to report the clinical, functional, and radiographic outcomes of a continuous series of 19 cases of knee arthrodesis using a customized modular intramedullary nailing system. HYPOTHESIS: The modular intramedullary nail offers a satisfactory functional result while maintaining limb length, in spite of a nonunion risk, since acting like a true endoprosthesis. MATERIAL AND METHODS: In our retrospective series of 19 patients, the main source of patients were infected total knee replacements. The nail was customized from assembling a dual surface-sanded titanium component (femoral and tibial). The Lequesne Algofunctional score and the WOMAC score were recorded, as well as the length discrepancy between the lower extremities. Arthrodesis consolidation and the nail's fit in the shaft were verified on anterior-posterior (AP) and lateral radiographs. RESULTS: Five complications were observed: one anterior cortical break, one excessive tibial rotation, two cases of delayed union, and one nail revision due to residual nail instability. The postoperative Lequesne Algofunctional score was 13/24 and the WOMAC score 57/100. The nonunion rate was 32%. From a functional point of view, the patients who did not achieve complete union and those who did had similar scores. The subjective results were not as good in patients who did not achieve final consolidation. DISCUSSION: Modular intramedullary nailing simplifies the technique, shortens the procedure, and reduces the amount of blood loss at surgery. Our nonunion rate was high, although the functional result did not seem compromised by such nonunion. The risk of long-term implant failure was not studied and requires longer follow-up studies. LEVEL OF EVIDENCE: Level IV therapeutic study.

The spectrum of adverse reactions after treatment with injectable fillers in the glabellar region: results from the Injectable Filler Safety Study.

BACKGROUND: For the glabellar region, severe partly vascular adverse events have been reported after treatment with injectable fillers. METHODS AND MATERIALS: For this study, data from the Injectable Filler Safety Study, a German-based registry for those reactions, was analyzed to characterize adverse events seen in the glabellar region. Patients were analyzed descriptively. RESULTS: Forty of 139 registered patients reported adverse events in the glabellar region. All patients were female, with an average age of 52.3. Nineteen patients with adverse reactions to hydroxyethylmethacrylate (HEMA) and ethylmethacrylate (EMA) in a fixed combination with hyaluronic acid (HA) and 10 patients with adverse reactions to different hyaluronic acid products were reported; five patients reacted to poly-L-lactic acid (PLA). The most common adverse reactions to HEMA/EMA in HA and PLA were nodules and hardening. In HA-treated patients, erythema and inflammation, swelling, and pain were most frequent. The adverse reactions to HEMA/EMA in HA were severe in 50% of the patients. Severe adverse reactions were found to a lesser extent in patients treated with HA and PLA. Potential vascular complications were documented in only two patients. CONCLUSION: Adverse reactions seen in the glabella are overwhelmingly product associated and to a lesser extent location associated. Vascular complications with necrosis and ulceration were rare.

Residual monomer: effect on tensile bond strength of silicone resilient liners / Monômero residual: o efeito na resistência de união de reembasadores resilientes de silicone

Adhesion failure between silicone resilient liner materials and denture base resin is a common problem found in clinical practice. Bond failure results in localized unhygienic conditions at the debonded regions and causes functional failure of the prosthesis. The aim of this study was to evaluate the tensile bond strength of 2 resilient liners (auto-polymerized silicone - Permafix® and heat-polymerized silicone - Permaflex®) under the influence of a residual monomer methylmethacrylate ([MMA]R) concentration. Two polymethyl methacrylate (PMMA) specimens were prepared by implementing brass dies by means of a 3 mm thick spacer in a denture flask. Specimens (20 X 10 X 3 mm) were made by processing the resilient liners against the polymerized PMMA blocks. After polymerization, the brass spacer was removed from the mold, the PMMAblocks were trimmed, and the bonding surfaces were smoothed. The PMMA blocks were placed back into the molds and resilient liners were packed into the space provided by the brass spacer, followed by trial packing and polymerization according to manufacturer instructions. Twenty specimens...

Falha na união entre reembasadores resilientes de silicone e base acrílica da prótese é um problema encontrado na prática clínica. A falha na união resulta em condições anti-higiênicas localizadas em regiões que apresentam descolamento, além de causar perda de função das próteses. O objetivo deste trabalho foi avaliar a resistência de união de 2 reembasadores resilientes de silicone (autopolimerizável - Permafix® and termopolimerizável - Permaflex®) sob a influência da concentração do monômero residual metilmetacrilato ([MMA]R). Duas amostras de polimetilmetacrilato (PMMA) foram obtidas por meio da inclusão de matrizes metálicas separadas por um espaçador com 3mm de espessura em mufla. As amostras (20 X 10 X 3 mm) foram obtidas processando o material resiliente contra os blocos de PMMA polimerizados. Após a polimerização, removeu-se o espaçador, submeteram-se os blocos ao processo de acabamento, sendo as superfícies de união alisadas. Os blocos foram recolocados no molde e o material resiliente condensado no local...

[Treatment of acute and chronic osteomyelitis in children]. / Behandlung von akuter und chronischer Osteomyelitis im Kindesalter.

AIM: Different studies in the past have reported about the treatment of osteomyelitis. None of these analysed the long-term results and complications after surgical treatment of acute and chronic osteomyelitis. The aim of this study was to analyse the recurrence rate and sequelae of osteomyelitis patients. PATIENTS AND METHODS: We analysed 53 children who were treated surgically between 1992 and 2004 for acute (n = 13) and chronic (n = 40) osteomyelitis. The histopathology was used for differentiation. With an average follow-up of 7.1 years (2 - 12.5 years) we examined the recurrence rate and the medical condition. RESULTS: A causative organism was identified in 53.9 % of the children with acute (AOM) and in 17.5 % of the children with chronic osteomyelitis (COM). In most cases Staphylococcus aureus could be isolated. Local antibiotics were applied intraoperatively to 92.3 % of the children with AOM and to 90 % of the children with COM. Additionally, the children with AOM were treated for 56.7 days (14 - 104 days) and the children with COM for 49.1 days (6 - 130 days) with parenteral/oral antibiotics. 2 (15.4 %) children with AOM and 6 (15 %) children with COM had a recurrence. At the time of the last examination all children were free of recurrence. One of the patients with AOM had a painless motion deficit of the shoulder. 5 children with COM complained of either pain and reduced range of motion of the affected extremity or minor deformities. CONCLUSION: Infantile osteomyelitis requires a selective diagnostic approach and an immediate parental antibiosis. If the antibiotic treatment fails, abscesses or sequestra are formed, an operation is indicated. With an adequate multidisciplinary cooperation, recurrence and sequelae can be avoided.

[ Improvement of femoral bone-cement adhesion in cemented revision hip arthroplasty by application of an amphiphilic bonder in a dynamic femur expulsion testing in vitro ]. / Steigerung der femuralen Knochen-Knochenzement-Verbundfestigkeit in der zementierten Revisionshüftendoprothetik durch einen amphiphilen Knochenhaftvermittler im dynamischen in-vitro Ausstossversuch.

Cemented femoral stems have shown decreased longevity compared to cementless implants in hip revision arthroplasty. The aim of this study was to evaluate the effect of an amphiphilic bonder on bone cement stability in a biomechanical femur expulsion test. A simplified hip simulator test setup with idealised femur stem specimens was carried out. The stems were implanted into bovine femurs (group 1: no bonder, n=10; group 2: bonder including glutaraldehyde, n=10; group 3: bonder without glutaraldehyde, n=10). A dynamic loading (maximum load: 800 N; minimum load: 100 N; frequency: 3 Hz; 105 cycles) was performed. Subsequently, the stem specimens were expulsed axially out of their implant beds and maximum load at failure was recorded. The static controls showed a mean maximum load to failure of 4123 N in group 1, 8357.5 N in group 2 and 5830.8 N in group 3. After dynamic loading, the specimens of group 2 reached the highest load to failure (8191.5 N), followed by group 3 (5649.5 N) and group 1 (3462 N), respectively. In group 2, we observed nine periprosthetic fractures at a load of 8400 N without signs of interface loosening. Application of an amphiphilic bonder led to a significant improvement of bonding stability, especially when glutaraldehyde was added to the bonder. This technique might offer an increased longevity of cemented femur revision stems in total hip replacement.