Bone infection occurring after fractures or orthopedic surgery can progress to the chronic stage and lead to poor results of treatment. Optimal treatment of chronic osteomyelitis are stabilization the fracture, biological recovery of bone defects and destroy bacterial infection. Traditional methods of treatment are systemic administration of antibiotics and surgical treatment of active infection focus. Systemic antibiotics are part of the standard therapy after surgical treatment of infected bone, but their effectiveness is limited due to malnutrition and low absorption at the site of infection. Moreover, long-term treatment and higher doses are associated with serious side effects. The aim of this investigation was to study the results of the complex treatment of patients with chronic osteomyelitis using biodegradable nanomaterials “PerOssal” as antibiotic delivery system. The study was performed at Regional center traumatology and orthopedics, Karaganda, Kazakhstan. A total 20 patient with post-traumatic/post-operative osteomyelitis were included in this open-label, prospective study. Bacteriological examination was taken with the determination of culture and sensitivity test preoperatively, during and postoperatively. After radical surgical debridement and ultrasound cavitation, the bone cavity was full filled with Perosal which can be loaded with different antibiotics depending from the antibiotic sensitivity test. Postoperative wound is completely was sutured. Systemic antibiotic treatment are allowed. The course of infection was monitored by determination leukocyte count and blood sedimentation rate; blood samples were taken befor, 24 hours after surgery, and on days 3, 7, 10, 14. Wound healing was assessed on days 2, 3, 7, 10, and at the time of removal of sutures. Resorption of implanted beads and bone reconstruction were evaluated by X-ray at after operation and at approximately one, three and six months after implantation. A total of 20 patients (mean age 38,1 (26 to 53), 14 male, 6 female) were treated with Perossal pellets (AAP, Germany) from October 2013 to April 2015. Mean leukocyte counts and blood sedimentation rate were within the normal laboratory range and did not indicate infectious complications during the first 21 days after surgery. Primary wound healing occurred in 18 patients and secondary wound healing in two patients. There were two cases of re-infection during the course of the study, one of them related to an incomplete eradication of infected tissue and multidrug-resistant strain occurring during the course of the study, the other is occurred that patient non-compliance. Radiographic analysis six months after surgery showed progressive resorption of the implanted pellets, but only 10 cases have decreasing size of defects on X-ray. This study in adult patients with chronic post-traumatic/post-operative osteomyelitis demonstrated that these biodegradable bone filler pellets which can be loaded with different antibiotics are a clinically useful local antibiotic delivery system and bone substitute which can be used as an alternative to other anti-infective implants. The implantation of the pellets was safety and well tolerated in all patients. This composite can provide adequate protection against bacterial infection during the first weeks after implantation and to support the bone healing process

Background. The different biodegradable local antibiotic delivery systems are widely used in recent years. The aim of this study was to evaluate the bactericidal activity antibiotic loaded PerOssal pellet in vitro and its effectiveness in the treatment of Staphylococcus aureus induced chronic osteomyelitis. Material and methods. MALDI-TOF have been applied to microbiological diagnosis in patient with osteomyelitis. In most cases, Staphylococcus aureus was isolated. In vitro Ceftriaxone-Loaded PerOssal pellet were placed in middle agar plate containing a stock strain of Staphylococcus aureus. Plates were incubated at 37ºC for 24 hours. The zones of bacterial inhibition were recorded after 24, 48 and 72 hours of incubation. In vivo evaluation was performed by prospectively studying of 21 patients with a clinically and bacteriologically diagnosed Staphylococcus aureus induced osteomyelitis. Mean age was 38±4,2(26 to 53)). After radical surgical debridement and ultrasound cavitation, the bone cavity was full filled with Perosal pellets loaded with different antibiotics depending from the antibiotic sensitivity test. Endpoints were the absence of clinical manifestation of infection or disease recurrence, no need for further surgery. Results. In vitro showed after 24 hrs inhibition zone was 4,2 х 4,9 cm, after 72 hrs the inhibition zone was increased till 7,6 х 8,4 cm. During the subsequent time, there were no changes. Results of the clinical study evidenced no signs of infection in 18 patients (86% (CI 69,8;100)) (p<0,05) at the follow up, while 3 (14%(CI 0;30,2)) (p<0,05) subjects showed infection recurrence at 6 months from operation and 2 of them needed further surgical procedures. Conclusion. PerOssal as an antibiotic carrier stabilizes the action of the antibiotic. This antibiotic carrier system allows to choose an antibiotic individually for each patient according to the antibiotic sensitivity test and can be successfully used in clinical cases of osteomyelitis

Purpose. Gustilo type III open fractures are associated with high infection rates in spite of instituting a standard of care (SOC) consisting of intravenous antibiotics, irrigation and debridement (I&D), and delayed wound closure. Locally-delivered antibiotic has been proven to assist in reducing infection in open fractures. The aims of this study are to determine the effectiveness and safety of a new implantable and biodegradable antibacterial product. 1. in preventing bacterial infections and initiating bone growth in open fractures. Methods. The osteoconductive antibacterial BonyPid. TM. used is a synthetic bone void filler (comprised of ≤1 mm β-tricalcium phosphate granules) coated by a thin layer (≤20 µm) of PolyPid nanotechnology formulation. −. Upon implantation, the coating releases doxycycline at a constant rate for a predetermined period of 30 days. One BonyPid. TM. vial of 10 grams contains 65 mg of formulated doxycycline. After approval, sixteen subjects with Gustilo type III open tibia fractures, were implanted with the BonyPid. TM. immediately on the first surgical intervention (I&D), followed by external fixation. Patients had periodic laboratory, bacteriology and radiology follow-up. Results. Six months results showed that no infection developed and only one BonyPid. TM. implantation was needed with no subsequent I&D, in the target tibia fracture. Immediate soft wound closure was done in 6/16 subjects following implantation. Out of 10 remaining subjects, 3 needed soleus muscle transfer-skin grafting and 7 required delayed primary closure; by skin grafting (5) or suturing (2). Early callus formation was seen at 8–12 weeks post-surgery, followed by bone healing seen from 16 weeks onwards. Safety of implantation was remarkable, with only one deep infection at a fibular open fracture without BonyPid. TM. implantation. One BonyPid. TM. -related adverse event caused delay in skin healing due to excessive granules in the superficial soft tissues. Conclusion. BonyPid. TM. is effective in reducing bone infection and promoting early callus formation, resulting in early bone healing. BonyPid. TM. is safe for immediate implantation into contaminated/infected severe open-bone fractures. Results support that one month release of doxycycline in a controlled manner provides an effective way for treating open fractures. This new local antibiotic delivery system is applicable in unmet medical situations associated with localised infections

Bacterial infection of bone may result in bone destruction which is difficult to cure due to poor accessibility to bone of systemically-administrated antibiotic and poor performance of currently available local antibacterial treatments. PolyPid Ltd developed a novel local drug delivery system based on self-assembly of pharmaceutically approved lipids and polymers that encapsulate doxycycline (Doxy). The formulation is self-assembled lipid matrix via the interaction of the lipids (cholesterol and synthetic phospholipids) and biocompatible - biodegradable polymer (poly-lactic-co-glycolic). The entrapped Doxy is located within the anhydrous environment and therefore fully protected from both enzymatic and long-term water-exposure-related degradation. The fine coating of the tri-calcium phosphate (TCP) bone filler by this Doxy-containing formulation (BonyPid™) is capable of releasing intact and active drug at zero-order kinetics for a predetermined period of up to 30 days. The coating of the TCP granules with the polymer-lipids-Doxy formula (BonyPid™) did not change the granules’ macroscopic shape, but altered its color from white to pale yellow, which resemble the color of the entrapped Doxy. The average sizes of the non-coated TCP granules and the coated granules BonyPid™ were similar, as determined by measuring the widest dimension of each granule (1135±241 µm and 1072±242 µm, respectively, P=0.16). The MIC for Doxy that was released from BonyPid™ at different time points was similar to the non-encapsulated Doxy, suggesting full bioavailability of the released drug. BonyPid™ formulation structure was characterised by different physical methods including wide angle X-ray analyses (WAXS), differential scanning calorimetric (DSC) and SEM. WAXS analyses of BonyPid™ samples show a strong signal in the range of 1.3–1.8 2θ°, suggesting that the polymer and lipid TCP coating is a highly organised nano-substructure. The principle lipid in BonyPid™ formulation is phosphatidylcholine, which constitutes more than 85% of the overall lipid mass. It was found that the length of the acyl chains (14, 16 and 18 carbons, respectively) can significantly alter the release rate of Doxy during the prolonged (30 days), zero-order release phase, but did not alter the release profile. The anti-infection activity of BonyPid™ was tested in the rabbit tibia model contaminated with 5×10. 5. S. aureus. Both acute and chronic infection models were tested. Only BonyPid™ treatment demonstrated a statistically significant reduced bone absorption over the infected group (P<0.04 for day 7, 14 and 21) and significantly lower bacterial bone concentration (p>0.05) on day 21 following the bone grafting and the bacterial inoculation. In addition it was found that BonyPid™ did not reduce the osteo-conductivity as compared to non-coated TCP bone-filler. The first-in-man study for the treatment of contaminated / infected severe open long-bone fractures of BonyPid™ completed its 6 months follow-up. The results demonstrated high safety profile and significant efficacy; early bone callus formation and 0% infections in the BonyPid™ target bone fracture. Conclusion. Results demonstrate that BonyPid™ nan-technology that allow one month release of doxycycline in a controlled manner provides a new way for treating open fractures. This new local antibiotic delivery system is applicable in other medical situations associated with localised infections

Objectives

Vancomycin and fosfomycin are antibiotics commonly used to treat methicillin-resistant Staphylococcus aureus (MRSA) infection. This study compares the in vitro inhibitory effects against MRSA of articulating cement spacers impregnated with either vancomycin or fosfomycin.