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Background: In fracture-related infections (FRI), both the diagnosis of the infection and the identification of the causative pathogen are crucial to optimize treatment outcomes. Sonication has been successfully used for periprosthetic joint infections (PJI); however, its role in FRI remains unknown. Our aim was to determine the diagnostic accuracy (sensitivity, specificity) of sonicate fluid culture (SFC). The primary objective was to compare SFC with peri-implant tissue culture (PTC) overall and among subgroups using the consensus definition by Metsemakers et al. The secondary objective was to determine the yield of SFC in possible fracture-related infections (PFRI)., Methods: From March 2017 to May 2019, 230 cases of retrieved implants were retrospectively reviewed. To perform sonication, explants were placed in sterile polypropylene jars intraoperatively. After treatment in an ultrasonic bath (Bandelin, Berlin, Germany), sonicate fluid was incubated into blood culture bottles, and conventional culturing was eventually performed. Sensitivity and specificity were determined using two-by-two contingency tables. McNemar's test was used to compare proportions among paired samples while Fisher's exact test was used for comparison between categorical variables., Results: Of the 230 cases, 107 were identified as FRI, whereas 123 were aseptic revision cases (ARC). Of the latter, 105 were labeled as PFRI. Sensitivity of SFC was higher in comparison with PTC, although this did not reach statistical significance (90.7% vs. 84.1%; p = .065). The specificity of SFC was significantly lower than that of PTC (73.2% vs. 88.6%; p = .003). In PFRI, SFC yielded significantly more positive results than PTC (33/105 vs. 14/105; p = .003). Overall, 142 pathogens were identified by SFC, whereas 131 pathogens were found by PTC., Conclusions: We found that sonication of fracture fixation devices may be a useful adjunct in FRI, especially in "low-grade" infections lacking confirmatory clinical criteria. Standardized diagnostic protocols are warranted in order to further optimize the diagnostic accuracy.

Background: Removal of hardware with irrigation and debridement in patients with surgical site infections (SSIs) is performed commonly. However, the removal of hardware from patients with SSIs after spinal procedures is controversial. Moreover, primary spinal infections such as spondylodiscitis may require instrumentation along with surgical debridement. The purpose of this article was to evaluate critically and summarize the available evidence related to retention of hardware in patients with deep SSIs, and the use of instrumentation in surgical treatment of primary spinal infections. Methods: A literature search utilizing PubMed database was performed. Studies reporting the management of deep SSIs after instrumented spinal procedures, and of primary spinal infections using instrumentation published in peer-reviewed journals were included. Identified publications were evaluated for relevance, and data were extracted from the studies deemed relevant. Results: Because SSIs occur typically during the early post-operative period before stable bony fusion has been achieved, the removal of instrumentation may be associated with instability of the spinal column, pseudarthrosis, progressive deformity, pain, loss of function, and deterioration in the activities of daily living (ADL). Hence, early SSIs after spinal instrumentation are usually treated without removal of hardware. Moreover, primary spinal infections such as spondylodiscitis may require surgical debridement and instrumentation in cases with associated instability. Conclusions: Retaining or using instrumentation in patients with SSIs after spinal procedures or in patients with primary spinal infections, respectively, are commonly practiced in the field of spine surgery. Further evidence is required for the development of definitive algorithms to guide spine surgeons in decision making regarding the fate of instrumentation in the treatment of spinal infections.

Background: Surgical stabilization of rib fractures (SSRF) can be used to improve pulmonary mechanics; however, hardware infection is a morbid complication. Antibiotic impregnated beads have been used to suppress infection in orthopedic practices. We aimed to determine the efficacy of antibiotic beads for infected and at-risk SSRF hardware., Methods: This is a single institution retrospective review of adults (18 years or older) that received SSRF between 2009 and 2017. Infected and at-risk hardware were managed with antibiotic beads. The primary outcome was bony union of rib fractures., Results: There were 285 SSRF patients. Infection rate was 3.5%. Antibiotic beads were placed in 17 patients - 9 for infected hardware and 8 for prophylaxis. Increased body mass index (p = 0.04) and hemorrhagic shock at admission (p = 0.03) were risk factors for infection. There was 100% bony union post-operatively., Conclusion: SSRF hardware infection is morbid. Antibiotic beads can salvage SSRF hardware until bony union., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Patients with traumatic bladder rupture frequently have associated pelvic fracture. With increasing numbers of pelvic fractures fixed internally, there are concerns that conservative management of bladder rupture may increase the risk of pelvic metalware infection. This study aims to determine if operative repair of bladder rupture in comparison to conservative management with catheter drainage alone is associated with a lower rate of infection of internal fixation device for concurrent pelvic fracture., Methods: This is a retrospective cohort study of level IV evidence. From July 2001 through June 2013, 45 multi-trauma patients at a level 1 trauma centre were identified to have sustained bladder rupture with concurrent pelvic fracture requiring internal fixation. Clinicopathological data were extracted from the TraumaNET database, medical records and health-coding database. Patients were stratified into two retrospective cohorts, management with surgical repair and management with catheter drainage alone. Fischer's exact test was used to determine whether the rate of pelvic metalware infection was different in the two cohorts., Results: Of the 45 patients, 13 had intraperitoneal bladder rupture, 28 had extraperitoneal bladder rupture and four had combined intra-extraperitoneal bladder rupture. The median age for this cohort was 31. Bladder rupture was surgically repaired in 36 patients and managed conservatively with catheter drainage in nine patients. The rate of pelvic internal fixation device infection was lower in patients managed with surgical repair compared with conservative management (5.6% versus 33.3%, P = 0.047)., Conclusion: Operative repair of bladder rupture is associated with a lower rate of pelvic orthopaedic hardware infection in the presence of concurrent pelvic fracture requiring internal fixation., (© 2017 Royal Australasian College of Surgeons.)

Background: The aim of this study is to establish the bacterial epidemiology of chronic osteoarticular infections in adults, to study the susceptibility of the isolated strains to antibiotics and to demonstrate the influence of osteosynthesis material thereon., Patients and Methods: This is a retrospective study of 78 months, from January 2006 to June 2012, providing bacteriological samples from patients with osteitis and osteoarthritis in the Mohammed V military teaching hospital of Rabat. Isolation and identification of bacteria were made by bacteriological classical techniques. The antimicrobial susceptibility testing of the isolates was performed by disk diffusion agar method, as recommended by the Committee of the susceptibility of the French Society for Microbiology (CA-SFM)., Results: We collected 234 cases, 53% (n = 124) of patients without osteosynthesis material (group A) and 47% (n = 110) patients with osteosynthesis material (group B).We isolated 371 bacteria which 51.49 (n = 191) in group A and 48.51% (n = 180) in group B. Gram-positive cocci were the most frequent (n = 234), followed by the Gram-negative bacilli (n = 114) and the Gram-positive bacilli (n = 19). Our study shows that the rate of resistance to antibiotics in strains obtained from patients with osteosynthesis material is higher compared to those obtained from patients without osteosynthesis material., Conclusions: Chronic OA infection in adults is difficult to diagnose and treat. Its good management must be multidisciplinary.

We present a case of a 60-year-old woman with an invasive spinal infection with Staphylococcus pseudintermedius associated with a 15-year-old spinal fixation device and epidemiological contact with dogs. It was confirmed on blood culture and culture from pus from the epidural abscess and successfully treated using similar treatment as for a Staphylococcus aureus infection - 6 weeks of intravenous flucloxacillin 2 g four times daily with a 6 week follow-on course of oral clindamycin 450 mg three times daily. This case represents the first reported deep abscess forming infection with this recently discovered organism. This case highlights that (1) S. pseudintermedius has a potential for invasive zoonotic infection, (2) treatment as for S. aureus appears adequate for resolution of the case, (3) the increased use of the matrix-assisted laser desorption/ionisation time-of-flight identification technique is leading to more specific identification of previously unrecognised organisms., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Objective: This study evaluates the effect of negative pressure wound therapy with antiseptic instillation (NPWTi) in the clearance of infection and biofilm formation in an in vivo model of infected spinal implants compared to traditional treatment modalities., Materials and Methods: Five pigs underwent titanium rod implantation of their spinous processes followed by injection of 1 x 106 CFUs/100μL of methicillin-resistant Staphylococcus aureus through the fascia at each site. At 1 week postoperatively, an experimental arm of 3 pigs received NPWTi, and a control arm of 2 pigs received wet-to-dry dressings. The persistence of local infection in the experimental group was compared to the control group using tissue cultures. Biofilm development on spinal implants was evaluated using scanning electron microscopy., Results: Mean bacterial count showed a statistical difference between the experimental and the control groups (P < .05). Scanning electron microscopy revealed the presence of uniform biofilm formation across the surface of control group instrumentation, whereas the experimental group showed interrupted areas between biofilm formations., Conclusion: The authors concluded that NPWTi is associated with decreased bacterial load and biofilm formation compared to wet-to-dry dressings in an in vivo porcine model of infected spinal instrumentation.

Purpose: Cases of fracture-fixation device infection involving Staphylococcus lugdunensis are not frequent. The clinical characteristics and the choice of treatment strategies of these infections are not obviously known to date., Methods: We performed a review of fracture-fixation device infection involving S. lugdunensis managed by our centres., Results: Among the 38 cases of fracture-fixation device infection involving S. lugdunensis, 53% were located in the tibia. Most of our cases (87%) were chronic infections. Purulent discharge, which occurred in 79% of cases, was the most frequent clinical symptom, followed by pain in 63%, local inflammation in 55%, and fever in 37%. Bacteremia and severe sepsis occurred in 10% and 18% of cases, respectively. Four cases (10%) were treated exclusively with antimicrobial treatment alone. Thirty-four cases (89%) were treated with a combination of surgery with antimicrobial therapy including surgical debridement, antibiotics and osteosynthesis device retention in six cases (16%), and osteosynthesis device removal in 27 cases (71%). The mean length of antibiotic treatment was 119 days. The relapse rate was high that was not related to selection of resistant strains. Polymicrobial infection had no impact on clinical outcome. A combination of surgery with antimicrobial therapy was identified as a significant prognostic factor associated with remission (p = 0.042)., Conclusions: S. lugdunensis is probably involved in more infections than has been reported. Using appropriate microbiological methods laboratories should routinely identify the species of all coagulase-negative Staphylococci isolates involved in fracture-fixation device infection to better achieve the treatment strategies of fracture-fixation device infection involving S. lugdunensis.

Study Design: Retrospective case series., Objective: To determine relevant demographics, clinical presentations, and outcomes of surgical site infections (SSIs) after spinal instrumentation (SI) surgery caused by methicillin-resistant Staphylococcus epidermidis (MRSE)., Summary of Background Data: This is the first study looking specifically at MRSE-related SSIs after SI surgery., Methods: We performed a retrospective review of patients with MRSE-related SSIs from 665 consecutive cases of SI surgery performed between 2007 and 2014 at our institution., Results: During the study period, SSIs occurred in 21 patients. MRSE was isolated from cultures obtained from surgical wounds in nine of the 21 patients (43%). There were four males and five females with a mean age of 63.9 ± 15.1 years. Six patients presented with inflammatory signs, such as wound drainage, pyrexia, erythema, and elevated C-reactive protein. Three patients did not have signs of infection, but had early implant failure, and were diagnosed by positive cultures collected at the time of revision surgery. The mean time from index surgery to the diagnosis of infection was 23.6 days (range, 7-88 days). In one patient, the implant was removed before antibiotic treatment was administered because of implant failure. Eight patients were managed with antibiotics and implant retention. During the follow-up period, MRSE-related SSIs in seven of the eight patients were resolved with implant retention and antibiotics without the need for further surgical intervention. One patient did not complete the antibiotic course because of side effects, and implant removal was required to control the infection., Conclusion: Early detection, surgical debridement, and administration of appropriate antibiotics for a suitable duration enabled infection control without the need for implant removal in the treatment of MRSE-related SSI after SI surgery., Level of Evidence: 4.

Competing Interests: Competing interests: None declared.

Background: Surgical stabilization of rib fracture (SSRF) is increasingly used for treatment of rib fractures. There are few data on the incidence, risk factors, outcomes, and optimal management strategy for hardware infection in these patients. We aimed to develop and propose a management algorithm to help others treat this potentially morbid complication., Methods: We retrospectively searched a prospectively collected rib fracture database for the records of all patients who underwent SSRF from August 2009 through March 2014 at our institution. We then analyzed for the subsequent development of hardware infection among these patients. Standard descriptive analyses were performed., Results: Among 122 patients who underwent SSRF, most (73%) were men; the mean (SD) age was 59.5 (16.4) years, and median (interquartile range [IQR]) Injury Severity Score was 17 (13-22). The median number of rib fractures was 7 (5-9) and 48% of the patients had flail chest. Mortality at 30 days was 0.8%. Five patients (4.1%) had a hardware infection on mean (SD) postoperative day 12.0 (6.6). Median Injury Severity Score (17 [range, 13-42]) and hospital length of stay (9 days [6-37 days]) in these patients were similar to the values for those without infection (17 days [range, 13-22 days] and 9 days [6-12 days], respectively). Patients with infection underwent a median (IQR) of 2 (range, 2-3) additional operations, which included wound debridement (n = 5), negative-pressure wound therapy (n = 3), and antibiotic beads (n = 4). Hardware was removed in 3 patients at 140, 190, and 192 days after index operation. Cultures grew only gram-positive organisms. No patients required reintervention after hardware removal, and all achieved bony union and were taking no narcotics or antibiotics at the latest follow-up., Conclusions: Although uncommon, hardware infection after SSRF carries considerable morbidity. With the use of an aggressive multimodal management strategy, however, bony union and favorable long-term outcomes can be achieved., Level of Evidence: Therapeutic study, level V.

Aim: To determine the prevalence of infections according to their etiologic spectrum and antibiotic sensitivity in patients with or without implants and endoprostheses., Material and Methods: This retrospective study was conducted based on a customized study protocol on 773 cases admitted to the Clinic of Orthopedics - Traumatology of the Iaşi "Sf. Spiridon" Emergency Hospital in the interval January 1, 2003 - December 31, 2011 for postoperative infectious complication., Results: S. aureus was more frequently found in the patients without implant (58.2%) and in those with subcutaneous implant (45.5%); the lowest frequency was noticed in the patients with endoprosthesis (27.1%), the frequency distributions showing marked statistically significant differences (p = 0.001). P. aeruginosa was more frequently detected in the patient group with endoprosthesis (30.2%), while in the other groups it was found in approximately 7% (p = 0.001). The presence of Acinetobacter spp. was significantly higher in patients with deep implant (12.9%), with the lowest frequency noticed in the patients without implant (4.5%) (p = 0.029). Of the total isolated and identified types, 59.6% were non-multidrug-resistant (non-MDR), the remaining 40.4% being MDR types., Conclusions: S. aureus was the most frequent etiological agent in patients with or without cutaneous implant (45.5 and 58.2%, respectively), and P. aeruginosa (30.2%) in the endoprosthesized patients. Implementation of a preoperative screening protocol for the identification of healthy S. aureus carriers (Methicillin-sensitive S. aureus - MSSA/Methicillin-resistant S. aureus - MRSA) and subsequent decolonization would be an efficient way of reducing the incidence of infections caused by this bacterium.

Purpose: In contrast to a large amount of epidemiological data regarding the incidence of implant infections after fracture management, surprisingly few have been published concerning the success of their treatment., Methods: This was a single-centre cohort study at Geneva University Hospitals from 2000 to 2012 investigating the remission rates of orthopaedic implant infections after fracture repair and associated variables., Results: A total of 139 episodes were included: There were 51 women (37%) and 28 immunosuppressed (20%) patients with a median age and American Society of Anaesthesiologists (ASA) score of 51 years and 2 points, respectively. The infected implants were plates (n = 75, 54 %), nails (24, 17%), wires (20), screws (10), cerclage cables or wires (3), hip screws (4) or material for spondylodesis (3). A pathogen was identified in 135 (97%) cases, including Staphylococcus aureus (73, 52%), coagulase-negative staphylococci (20), streptococci (7) and 19 Gram-negative rods. All patients underwent antibiotic treatment, and 128 (92%) remained in remission at a median follow-up time of 2.6 years (range one to 13 years). In multivariate logistic regression analysis, the plate infections were significantly associated with lower remission rates [65/75, 87%, odds ratio (OR) 0.1, 95% confidence interval (CI) 0.01-0.90]. No associations were found for gender, age, immune status, ASA score, additional surgical interventions (OR 0.4, 95% CI 0.1-4.1) or duration of antibiotic treatment (OR 1.0, 95% CI 0.98-1.01)., Conclusions: Among all infected and removed orthopaedic implants, plates were associated with slightly lower remission rates, while the overall treatment success exceeded 90%. The duration of antibiotic therapy did not alter the outcome.

Background Context: Postoperative spine infections have been reported to occur in 1% to 15% of patients and subsequently lead to significant morbidity and cost, with an elevated risk for instrumented cases. Every effort should be made to minimize the risk of intraoperative wound contamination. Consequently, certain practices are followed in the operating room to prevent contamination, many of which are not evidence based. Conversely, certain objects believed to be sterile are frequently overlooked as potential sources of contamination., Purpose: To assess to what degree contamination of spinal implants occurs during spine surgery and evaluate whether coverage of implants alters the rate of contamination., Study Design: Prospective study., Study Sample: This study included 105 consecutive noninfection surgical cases performed by a single spine surgeon that required the use of instrumentation., Outcome Measure: Spinal implant contamination., Methods: Cases were randomized to have all implant trays either remain uncovered (n=54) or covered (n=51) with sterile surgical towels on opening until implants were required for the case. After the last implant was placed, a sterile culture swab was used to obtain a sample from all open implants that had been present at the start of the case. The paper outer wraps of the implant trays were sampled in each case as a positive control, and an additional 105 swabs were capped immediately after they were opened to obtain negative controls. Swab samples were assessed for bacterial growth on 5% sheep blood Columbia agar plates. Of note, only departmental funding was used and no applicable financial relationships exist with any author., Results: No growth was observed on any of the 105 negative controls, whereas 99.1% of positive controls demonstrated obvious contamination. Cultures from implant samples demonstrated a 9.5% overall rate of contamination with 2.0% (n=1) of covered implants versus 16.7% (n=9) of uncovered implants demonstrating contamination. Length of time implant trays were open before sample collection; implant type (plate, rods, vs. polyetheretherketone), number of scrubbed personnel, and number of implants used were all not found to be significantly associated with implant contamination (p>.05). However, coverage of implants was found to significantly reduce the implant contamination rate (p=.016)., Conclusions: The contamination of sterile implants during spine surgery was found to occur. However, this contamination was independent of the amount of time the implant trays remained open. Coverage of implants significantly reduces this contamination. Therefore, no matter the expected duration of a case, implant coverage is a simple modifiable way to reduce the risk of intraoperative wound contamination and potentially reduce postoperative infections., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Surgical-site infection is a common form of noscomial infection that can occur in fractures following internal fixation. Treatment of these infections has traditionally included preserving stable implants via debridement and antibiotic administration while the fracture is healing. Recent evidence indicated that this algorithm results in less-than-optimal rates of fracture union and infection eradication.The premise for this study is that bacterial removal from fracture implants using the Versajet Hydrosurgery System (Smith & Nephew, Memphis, Tennessee) method is better compared with the bulb syringe and pressurized pulsatile lavage methods. Thirty-two stainless steel, 4-hole, nonlocking, 3.5-mm fracture plates were incubated with Staphylococus aureus and divided into 4 groups. Eight plates in each group underwent irrigation with 1 L of saline using a bulb syringe lavage, pressurized pulsatile lavage, or the Versajet Hydrosurgery System method. Eight plates underwent no irrigation method and served as a control group. The residual bacterial loads following irrigation were quantitatively cultured. Each of the experimental groups had significantly reduced levels of bacteria adherent to the plate following irrigation compared with the control group (P=.0002). Furthermore, the Versajet Hydrosurgery System was most the effective at bacterial removal, followed by the pressurized pulsatile and bulb syringe lavage techniques (P=.0002 to P=.0012, respectively).Novel approaches to eradicate bacteria from implants, such as hydrosurgery technology, while maintaining rigid stability of healing fracture, may improve clinical outcomes., (Copyright 2012, SLACK Incorporated.)

Study Design: Retrospective review of database patients., Objective: To compare infectious pin complication rates utilizing ceramic pins, an emerging technology, with a large database of complications in halo's using metallic pins., Summary of Background Data: The halo/vest fixator remains a useful modality of treatment for cervical spine trauma but has been described as having a high incidence of complications, foremost pin-related complications. Ceramic pins and vest modifications have been introduced under the premise of (1) decreasing pin-tract infections compared with metallic pins manufactured from stainless steel or titanium and with the advent of 3T MRI, (2) decreasing brain MRI artifact, and (3) lowering MRI intolerance owing to material overheating., Material and Methods: We retrospectively reviewed a prospectively collected patient data set of the Harborview Medical Center spine trauma registry. A historic control group exclusively utilizing metallic halo pins over a 10-year period was compared with patients who were treated with halo's exclusively utilizing ceramic pins over a recent 14-month period. Complications investigated included aseptic, loosening, and infections graded on a novel 3-tier system adapted from external fixation in long bone and periarticular trauma. Inclusion criteria were the patients with traumatic cervical spine injuries treated with a halo for a period of at least 14 days., Results: Forty-four patients were available for analysis in the ceramic pin group versus 263 in the metallic pin group. Overall pin complications amounted to 40.9% ceramic (C) versus 21.7% metal (M) pins (P<0.05), aseptic loosening rates 13.7% (C) compared with 8.3% (M), and pin site infections 27.3% (C) compared with 13.3% (M) (P<0.05). A grading system for halo pin tract infections was developed. In assessing overall complications and infections specifically, ceramic pins seemed to be associated with a higher incidence of adverse events or complications compared with titanium pins., Conclusion: Despite the imbalance of size of our cohort groups, there seems to be a strong trend toward the newer ceramic pin technology not meeting expected minimum performance standards set by the earlier metallic material. Causes for the higher failure rate likely lay in the necessary changes made to the halo vest and specifically the pin design owing to the inherent mechanical property limitations of MRI compatible materials.

Orthopedic implant-related bacterial infections are associated with high morbidity that may lead to limb amputation and exert significant financial burden on the healthcare system. Staphylococcus aureus is a dominant cause of these infections, and increased incidence of community-associated methicillin-resistant S. aureus (CA-MRSA) is being reported. The ability of S. aureus to attach to the foreign body surface and develop a biofilm is an important determinant of resistance to antibiotic prophylaxis. To gain insight on CA-MRSA biofilm properties, USA300 biofilm maturation and dispersal was examined, and these biofilms were found to exhibit pronounced, quorum-sensing mediated dispersal from a glass surface. For comparison of biofilm maturation on different surface chemistries, USA300 biofilm growth was examined on glass, polycarbonate, and titanium, and minimal differences were apparent in thickness, total biomass, and substratum coverage. Importantly, USA300 biofilms grown on titanium possessed a functional dispersal mechanism, and the dispersed cells regained susceptibility to rifampicin and levofloxacin treatment. The titanium biofilms were also sensitive to proteinase K and DNaseI, suggesting the matrix is composed of proteinaceous material and extracellular DNA. These studies provide new insights on the properties of CA-MRSA biofilms on implant materials, and indicate that quorum-sensing dispersion could be an effective therapeutic strategy.

Study Design: A retrospective case series., Objective: To determine if implant retention is possible in spinal deformity cases which present as a delayed (greater than 3 months) surgical site infection., Summary of Background Data: The retention of spinal implants in deformity surgery is possible with an acute surgical site infection. Currently, the decision whether or not to retain implants in a delayed surgical site infection is unclear., Methods: A retrospective review of 26 cases of delayed surgical site infections after spinal deformity surgery. Data and information was recorded regarding the initial management of the surgical site infection, the number of operations performed related to the infection, and whether or not the infection could be cleared with implant retention. The number of operations, hospital days, and charges related to the treatment of the infection were recorded., Results: In this series, no patient was able to clear their infection without spinal implant removal. The number of operations required to clear the infection, length of hospitalization, and financial charges were proportionate to the timing of implant removal., Conclusion: Delayed surgical site infections after spinal instrumentation for deformity need to be treated with implant removal to clear the surgical site infection. Patients may require to undergo repeat instrumentation and fusion at a later date if they develop progressive deformity or symptomatic pseudarthrosis after implant removal.

Study Design: A retrospective study about Propionibacterium acnes infections after Cotrel-Dubousset (CD) instrumentation., Objectives: To analyze the significance of P. acnes-positive deep samples after CD., Summary of Background Data: The diagnosis of spinal infections to P. acnes after CD is difficult., Methods: Patients with revision surgery and at least 1 P. acnes-positive deep sample, between 2000 and 2006 were included. Group A had 1 revision surgery and group B had 2 successive revision surgeries, with P. acnes-positive deep samples. Group A was divided into 2 subgroups according to the peroperative macroscopic aspect, subgroup A1 with septic tissues, subgroup A2 without septic tissues. The biologic characteristics of the patients and the surgical and medical treatments were assessed., Results: Sixty-eight patients were included, 60 in group A (A1 = 33, A2 = 27) and 8 in group B. Group A: 26 patients had 1 or 2 P. acnes-positive samples and 34 had at least 3 P. acnes-positive samples. Histology showed chronic inflammatory changes. C-reactive protein value median rate was 42 (A1) and 5 mg/L (A2). Twenty-two patients had a complete implant removal (14 with antibiotics, A1 = 12, A2 = 2). Nine patients had a total implant replacement (7 with antibiotics). Twenty-two patients had a partial implant removal (17 with antibiotics, A1 = 5, A2 = 12). Seven A1 patients had an irrigation and debridement (6 with antibiotics). The evolution was favorable for 28 patients. Seven patients had a documented sepsis. Group B: during the first revision, 8 patients had a partial implant removal (2 with antibiotics); during the second revision, all patients received antibiotics 4 of whom had a total implant removal. The long-term evolution was favorable for 6 patients., Conclusion: P. acnes infection of spinal instrumentation is difficult to diagnose. Results of at least 4 deep sample cultures, histology, and C-reactive protein values must be compared to the peroperative macroscopic aspect.

In this study, we investigated the in vitro efficacy of clarithromycin (CLA) combined with cefazolin (CFZ) or vancomycin (VCM) against Staphylococcus aureus biofilms formed on titanium devices in order to confirm the efficacy of eradication therapies against device-related infection. The distribution of CLA in muscle tissue surrounding bone was also investigated by liquid chromatography/tandem mass spectrometry in 10 orthopaedic patients. Biofilm formation and eradication of S. aureus were monitored by scanning electron microscopy and using double-staining dyes, respectively. Although S. aureus biofilms were not eradicated by CLA, CFZ or VCM alone, CLA combined with CFZ or VCM destroyed biofilms, and S. aureus eradication was clearly observed 72 h later. This in vitro study showed that treatment with CLA plus CFZ or VCM destroyed staphylococcal biofilms formed on medical devices and eradicated S. aureus.

In this study the presence both of the ica genes, encoding for biofilm exopolysaccharide production, and the insertion sequence IS256, a mobile element frequently associated to transposons, was investigated in relationship with the prevalence of antibiotic resistance among Staphylococcus epidermidis strains. The investigation was conducted on 70 clinical isolates derived from orthopedic implant infections. Among the clinical isolates investigated a dramatic high level of association was found between the presence of ica genes as well as of IS256 and multiple-resistance to all the antibiotics tested (oxacillin, penicillin, gentamicin, erythromycin, clindamycin, chloramphenicol, sulfamethoxazole + trimethoprim, ciprofloxacin, vancomycin). Noteworthy, a striking full association between the presence of IS256 and resistance to gentamicin was found, being none of the IS256-negative strain resistant to this antibiotic. This association is probably because of the link of the corresponding aminoglycoside-resistance genes, and IS256, often co-existing within the same staphylococcal transposon. In conclusion, in orthopedics, the presence of ica genes and that of IS256 in S. epidermidis genome should both be considered as informative markers of clinically relevant strains equipped with greatest and broadest resistance potential to survive to medical treatments., (Copyright 2007 Wiley Periodicals, Inc.)

Purpose: Infected spinal stabilization devices represent a significant reconstructive challenge by threatening spinal stability and increasing the risk of neurologic complications. This study provides an anatomic and clinical investigation of posterior midline trunk reconstruction using paraspinous muscle flaps as the primary method of repair., Methods: We retrospectively analyzed a series of 25 consecutive patients (mean age, 57.2 years; range, 32-78 years) with complex spinal wounds, reconstructed with paraspinous muscle flaps, at a single university healthcare system. To help define the versatility of these muscle flaps, we also performed cadaveric dissections with lead oxide injections in 10 specimens, with an emphasis on regional blood supply, flap width, and arc of rotation., Results: From 1994 to 2000, we successfully reconstructed 25 patients with complex spinal wounds, using 49 paraspinous muscle flaps as the primary method of reconstruction. Hardware present in 22 patients was replaced or retained in 17 cases. Long-term spinal fusion with preservation of neurologic status was observed in all patients, with no cases of dehiscence or reinfection. Wound complications included cerebrospinal fluid leak (1), skin necrosis (1), sinus tracts (3), and seroma (2). Mean length of stay was 24 days (range, 8-57 days). One postoperative death occurred. Paraspinous dissections and injections confirmed a segmental type IV blood supply with medial and lateral perforators, arising from intercostal vessels superiorly and lumbar and sacral vessels inferiorly. Flap width was 8 cm at the sacral base, 5 cm at the level of the inferior scapular angle, and 2.5 cm at the first thoracic vertebra., Conclusions: Paraspinous muscle flaps can be used as the primary reconstructive option to cover and preserve spinal hardware, control local infection, and enable long-term spinal stabilization. Cadaveric dissections confirmed the usefulness of paraspinous flaps, which can be based upon lateral or medial perforators and can be safely mobilized to reliably reconstruct complex spinal wounds.

Study Design: Case report., Objectives: To describe a case of infected vertebroplasty and to demonstrate the importance of polymerase chain reaction (PCR) in the diagnosis of such infections., Summary of Background Data: Infection of the vertebroplasty site is an uncommon complication of vertebroplasty. Only 4 cases have been reported in the literature so far, and an organism could be identified in only 2 of those cases. To our knowledge, the use of PCR to diagnose infection in these cases has not been reported before., Methods: Vertebroplasty, laminectomy, radiology, fluid aspiration, microbial culture, and 16S RNA PCR., Results: A 73-year-old diabetic woman underwent vertebroplasty for L2 and L3 vertebral compression fractures followed by L4-L5 laminectomy for spinal stenosis. Three months later, she had an L1 fracture that was augmented with vertebroplasty. Six months later, she presented with incapacitating low back pain. There was a fluid-filled cavity surrounding the polymethylmethacrylate in the L1 and L2 vertebral bodies. The fluid had 95,000 white blood cells with 96% neutrophils, grew nothing on culture, but had 100% homology with Streptococcus agalactiae on 16S ribosomal nucleic acid analysis., Conclusions: We report a case of infected vertebroplasty with atypical radiologic findings of vertebral infection. To our knowledge, this is the third reported case where an organism could be isolated for these infections and the first time PCR has been used to diagnose such an infection.

Background: We describe the management of osteomyelitis of the cervical spine, utilizing internal fixation with subsequent removal and culture of the implants. Four out of five patients had evidence of bacterial colonisation in close proximity to the internal fixation device., Methods: Five consecutive patients (all female, ranging in age from 50 to 74 yrs) presenting with unstable cervical osteomyelitis were treated by surgical decompression, primary internal fixation followed by three months of intravenous antibiotics. The internal fixation was removed in 4 out of 5 cases within a year of stopping the intravenous regime. The remaining patient was deemed medically unfit for further operation. Multiple specimens from the screw sites were taken at the time of metal removal. A final course of oral antibiotics was prescribed based on the results of these specimens., Findings: Four patients, who had removal of the implants, had positive cultures growing different bacteria from the primary infection, at the time of removal of the implant. None of the patients developed instability after removal of the implant., Interpretation: Asymptomatic bacterial colonisation of a metallic implant has profound management implications. We recommend long-term oral antibiotic regimes after insertion of internal fixation devices in the face of infection and eventual removal of these implants and microbiological re-sampling.

Objective: To determine the incidence of delayed infections in idiopathic scoliosis treated with TSRH instrumentation, proper wound management after instrumentation removal, and whether the previously identified bacterial trend remains consistent., Methods: All patients with idiopathic scoliosis > or =2 years after surgery with posterior TSRH instrumentation were included. Those cases with delayed infections were retrospectively reviewed. Time of presentation (infection) from index operation, clinical picture, sedimentation rate, presence of pseudarthrosis, organisms grown on culture, type of wound closure, and duration of antibiotics were examined., Results: A total of 489 patients were identified > or =2 years postoperation; 23 had delayed infections (4.7%). Time of presentation averaged 27 months after initial surgery. Spontaneous drainage occurred in 15 patients, fluctuance in 6, and neither in the remaining 2 (pain and fever). Sedimentation rate averaged 48 mm/hr. All patients had instrumentation removed. Primary closure (1 stage) was performed in 14 patients, and delayed primary closure (> or =2 stages) was performed in nine patients. All wounds healed uneventfully. Cultures at the time of instrumentation removal grew Propionibacterium acnes in 12 patients, Staphylococcus epidermidis (or Staphylococcus coagulase-negative) in 4, Micrococcus varians in 1, and Staphylococcus aureus in 1. Five patients had negative cultures. After removal, patients received parenteral antibiotics; in 21 of these patients this was followed by oral antibiotics., Conclusions: Low-virulent skin organisms are primarily responsible for delayed infections. Intraoperative seeding followed by subclinical quiescent periods appears to be the method by which infection occurs. The increased bulk and modularity of modern instrumentation systems can lead to inflammation and bursa formation, thus contributing significantly to the activation of these infections. Primary wound closure results in successful wound healing. Delayed closure after 48 hours is unnecessary. Short-term postoperative parenteral antibiotics (2-5 days) followed by short-term oral antibiotics (7-14 days) is recommended.