Risk factors for treatment failure of fracture-related infections.

OBJECTIVE: Infection after fracture fixation is a potentially devastating outcome, and surgical management is frequently unsuccessful at clearing these infections. The purpose of this study is to determine if factors can be identified that are associated with treatment failure after operative management of a deep surgical site infection. METHODS: We retrospectively reviewed the billing system at a Level I trauma center between March 2006 and December 2015. We identified 451 patients treated for deep surgical site infection after fracture fixation at our center. A multivariate regression analysis was then performed to evaluate for factors associated with treatment failure. RESULTS: Mean follow-up was 2.3 years. One hundred fifty-six patients (35%) failed initial surgical management. Risk factors associated with treatment failure included initial culture results positive for polymicrobial organisms (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.0-2.4), removal of implants (OR, 1.9; 95% CI, 1.2-2.9), or Gustilo-Anderson IIIB/IIIC injury (OR, 2.0; 95% CI, 1.1-3.7). Increased body mass index and fulfilling the criteria to have a methicillin-resistant Staphylococcus aureus (MRSA) nasal swab screening showed a trend toward increased risk of failure. CONCLUSION: Treatment failure after deep surgical site infection was relatively common. Three distinct factors (polymicrobial infection, removal of implants, and IIIB/C fracture) were associated with failure to eradicate the infection in the first series of surgeries and antibiotics. These data might help guide clinicians as they counsel patients on the risk of treatment failure and might focus efforts to improve treatment toward patients at higher risk of treatment failure.

Low-Intensity Pulsed Ultrasound for Nonoperative Treatment of Scaphoid Nonunions: A Meta-Analysis.

Background: Scaphoid fractures progress to nonunion rates of up to 15% when non-displaced, and are even more frequent when the fracture is displaced. Standard treatment in these cases is surgery; however, individuals unable to undergo this operation, or for those who wish to try more conservative measures, there may be benefit from nonoperative options. Of these, low-intensity pulsed ultrasound (LIPUS) has been shown to improve fracture nonunion healing. The purpose of this study was to perform a comprehensive meta-analysis of relevant literature to determine success of the use of LIPUS for treatment of scaphoid nonunion. Methods: Utilizing PubMed, Embase, and Ovid databases, we performed a literature search using key terms for scaphoid nonunions. A total of 686 studies met initial search criteria. Studies reporting fewer than 5 cases, those not published in English, those not related to LIPUS nonoperative scaphoid nonunion treatment, and those without sufficient data were excluded. Five studies met these criteria, and statistical analysis was performed to determine overall union rates. Results: The use of LIPUS on 166 nonunions reported a mean healing index of 78.6%. The average time to union following LIPUS treatment was 4.2 months. Conclusions: While surgical intervention is still the standard, our results show that LIPUS may serve as a nonoperative alternative to scaphoid nonunion in certain cases. The results are encouraging in which these challenging fracture a nonunions can heal without further surgical intervention in the majority of patients.

Peculiar citric acid cycle of hydrothermal vent chemolithoautotroph Hydrogenovibrio crunogenus, and insights into carbon metabolism by obligate autotrophs.

The genome sequence of the obligate chemolithoautotroph Hydrogenovibrio crunogenus paradoxically predicts a complete oxidative citric acid cycle (CAC). This prediction was tested by multiple approaches including whole cell carbon assimilation to verify obligate autotrophy, phylogenetic analysis of CAC enzyme sequences and enzyme assays. Hydrogenovibrio crunogenus did not assimilate any of the organic compounds provided (acetate, succinate, glucose, yeast extract, tryptone). Enzyme activities confirmed that its CAC is mostly uncoupled from the NADH pool. 2-Oxoglutarate:ferredoxin oxidoreductase activity is absent, though pyruvate:ferredoxin oxidoreductase is present, indicating that sequence-based predictions of substrate for this oxidoreductase were incorrect, and that H. crunogenus may have an incomplete CAC. Though the H. crunogenus CAC genes encode uncommon enzymes, the taxonomic distribution of their top matches suggests that they were not horizontally acquired. Comparison of H. crunogenus CAC genes to those present in other 'Proteobacteria' reveals that H. crunogenus and other obligate autotrophs lack the functional redundancy for the steps of the CAC typical for facultative autotrophs and heterotrophs, providing another possible mechanism for obligate autotrophy.

Scapular neck length and implications for reverse total shoulder arthroplasty: An anatomic study of 442 cadaveric specimens.

PURPOSE: Reverse total shoulder arthroplasty (RTSA) may be used to treat a variety of pathologic shoulder conditions, but complications such as scapular notching continue raise concerns. Variable anatomy surrounding the glenoid may have implications for future RTSA design, but at present the anatomy of the scapular neck in the human population has not been clearly defined. MATERIALS AND METHODS: 442 human scapulae from the Hamann-Todd Osteological Collection were measured for scapular neck length (SNL) and scapular neck angle (SNA). SNL was defined as the distance from the most lateral portion of the infraglenoid tubercle to the most inferolateral portion of the glenoid fossa. The SNA was measured according to Gerber et al. previously. The mean, standard deviation and ranges for SNL and SNA were calculated and compared based on sex and race, and interobserver variability was calculated. RESULTS: The mean SNL was 1.06 cm ± 0.33 cm (0.37-2.43 cm). Males demonstrated a larger SNL (1.08 cm ± 0.33 cm) than females (1.01 cm ± 0.32 cm) (P < 0.12), and Caucasians (1.09 cm ± 0.33 cm) demonstrated a significantly larger SNL than African-Americans (1.00 cm ± 0.32) (P < 0.01). The mean SNA was 106.7° ± 11.0° (76.9-139.4°). No significant correlation was found between SNL and SNA (Pearson Correlation Coefficient = 0.018) (P < 0.702). CONCLUSION: Scapular neck length and SNA vary widely within the population but there appears to be a tendency towards increased SNL in males and Caucasians. CLINICAL RELEVANCE: The anatomy of the scapular neck may have significant implications for RTSA design, surgical planning, and reduction of associated complications.