Delays to Surgery and Coronal Malalignment Are Associated with Reoperation after Open Tibia Fractures in Tanzania.

BACKGROUND: Treatment of diaphyseal open tibia fractures often results in reoperation and impaired quality of life. Few studies, particularly in resource-limited settings, have described factors associated with outcomes after these fractures. QUESTIONS/PURPOSES: (1) Which patient demographic, perioperative, and treatment characteristics are associated with an increased risk of reoperation after treatment of open tibia fractures with intramedullary nailing or an external fixation device in Tanzania? (2) Which patient demographic, perioperative, and treatment characteristics are associated with worse 1-year quality of life after treatment of open tibia fractures with intramedullary nailing or an external fixation device in Tanzania? METHODS: A prospective study was completed in parallel to a similarly conducted RCT at a tertiary referral center in Tanzania that enrolled adult patients with diaphyseal open tibia fractures from December 2015 to March 2017. Patients were treated with either a statically locked intramedullary nail or external fixator and examined at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year postoperatively. The primary outcome, reoperation, was any deep infection or nonunion treated with a secondary intervention. The secondary outcome was the 1-year EuroQol-5D (EQ-5D) index score. There were 394 patients screened and ultimately, 267 patients enrolled in the study (240 from the primary RCT and 27 followed for the purposes of this study). Of these, 90% (240 of 267) completed 1-year follow-up and were included in the final analysis. This group comprised 110 patients who underwent IMN and 130 who had external fixation; follow-up was similar between study groups. Patients were an average of 33 years old and were primarily males who sustained road traffic injuries resulting in AO/Orthopaedic Trauma Association (OTA) classification type A or B fractures. There were 51 reoperations. For the purposes of analysis, all patients were pooled to identify all other factors, in addition to treatment type, associated with increased risk of reoperation and 1-year quality of life. An exploratory bivariable analysis identifying various factors associated with reoperation risk and EQ-5D was subsequently included in a multivariate modeling procedure to control for confounding of effect on our primary outcome. Multivariable modeling was performed using standard hierarchical modeling simplification procedures with log-likelihood ratios. Alpha levels were set to 0.05. RESULTS: After controlling for potentially confounding variables such as gender, smoking status, mechanism of injury, and treatment type, the following factors were independently associated with reoperation: Time from hospital presentation to surgery more than 24 hours (odds ratio 7.7 [95% confidence interval 2.1 to 27.8; p = 0.002), AO/OTA fracture classification Type 42C fracture (OR 4.2 [95% CI 1.2 to 14.0]; p = 0.02), OTA-Open Fracture Classification muscle loss (OR 7.5 [95% CI 1.3 to 42.2]; p = 0.02), and varus coronal angle on an immediate postoperative AP radiograph (OR 4.8 [95% CI 1.2 to 14.0]; p = 0.002). After again controlling for confounding variables such as gender, smoking status, mechanism of injury, and treatment type factors independently associated with worse 1-year EQ-5D scores included: Wound length ≥ 10 cm (ß = [change in EQ-5D score] -0.081 [95% CI -0.139 to -0.023]; p = 0.006), OTA-Open Fracture Classification muscle loss (ß = -0.133 [95% CI -0.215 to -0.051]; p = 0.002), and OTA-Open Fracture Classification bone loss (ß = -0.111 [95% CI -0.208 to -0.013]; p = 0.03). We observed a modest, but independent association between reoperation and worse 1-year EQ-5D scores (ß = -0.113 [95% CI -0.150 to -0.077]; p < 0.001). CONCLUSIONS: We found two potentially modifiable factors associated with the risk of reoperation: reducing time to surgical treatment and avoiding varus coronal angulation during definitive stabilization. Hospitals may be able to minimize time to surgery, and thus, reoperation, by increasing the number of available operative personnel and space and emphasizing the importance of open tibia fractures as an injury requiring emergent orthopaedic management. Given the lack of fluoroscopy in the study setting and similar settings, surgeons should emphasize appropriate fracture alignment, even into slight valgus, to avoid varus angulation and subsequent reoperation risk. LEVEL OF EVIDENCE: Level II, therapeutic study.

Clinical Outcomes and Qualitative Perceptions of In-person, Hybrid, and Virtual Cardiac Rehabilitation.

PURPOSE: Cardiac rehabilitation (CR) is evolving to include both in-person and virtual delivery. Our objective was to compare, in CR patients, the association of in-person, hybrid, and virtual CR with change in performance on the 6-min walk test (6MWT) between enrollment and completion. METHODS: Patients enrolled in CR between October 22, 2019, and May 10, 2021, were categorized into in-person, hybrid, or virtual groups by number of in-person and virtual visits. All patients received individualized exercise training and health behavior counseling. Cardiac rehabilitation was delivered to patients in the hybrid and virtual cohorts using synchronous video exercise and/or asynchronous telephone visits. Measurements at CR enrollment and completion included the 6MWT, blood pressure (BP), depression, anxiety, waist-to-hip ratio, and cardiac self-efficacy. RESULTS: Of 187 CR patients, 37/97 (38.1%) were in-person patients and 58/90 (64.4%) were hybrid/virtual patients ( P = .001). Compared to in-person (51.5 ± 59.4 m) improvement in the 6MWT was similar in hybrid (63.4 ± 55.6; P = .46) and virtual (63.2 ± 59.6; P = .55) compared with in-person (51.5 ± 59.4). Hybrid and virtual patients experienced similar improvements in BP control and anxiety. Virtual patients experienced less improvement in depression symptoms. There were no statistically significant changes in waist-to-hip ratio or cardiac self-efficacy. Qualitative themes included the adaptability of virtual CR, importance of relationships between patients and CR staff, and need for training and organizational adjustments to adopt virtual CR. CONCLUSIONS: Hybrid and virtual CR were associated with similar improvements in functional capacity to in-person. Virtual and hybrid CR have the potential to expand availability without compromising outcomes.

From Detection of Individual Metastases to Classification of Lymph Node Status at the Patient Level: The CAMELYON17 Challenge.

Automated detection of cancer metastases in lymph nodes has the potential to improve the assessment of prognosis for patients. To enable fair comparison between the algorithms for this purpose, we set up the CAMELYON17 challenge in conjunction with the IEEE International Symposium on Biomedical Imaging 2017 Conference in Melbourne. Over 300 participants registered on the challenge website, of which 23 teams submitted a total of 37 algorithms before the initial deadline. Participants were provided with 899 whole-slide images (WSIs) for developing their algorithms. The developed algorithms were evaluated based on the test set encompassing 100 patients and 500 WSIs. The evaluation metric used was a quadratic weighted Cohen's kappa. We discuss the algorithmic details of the 10 best pre-conference and two post-conference submissions. All these participants used convolutional neural networks in combination with pre- and postprocessing steps. Algorithms differed mostly in neural network architecture, training strategy, and pre- and postprocessing methodology. Overall, the kappa metric ranged from 0.89 to -0.13 across all submissions. The best results were obtained with pre-trained architectures such as ResNet. Confusion matrix analysis revealed that all participants struggled with reliably identifying isolated tumor cells, the smallest type of metastasis, with detection rates below 40%. Qualitative inspection of the results of the top participants showed categories of false positives, such as nerves or contamination, which could be targeted for further optimization. Last, we show that simple combinations of the top algorithms result in higher kappa metric values than any algorithm individually, with 0.93 for the best combination.

Nitric oxide synthase inhibition during development: effect on apoptotic death of dopamine neurons.

Naturally occurring cell death via apoptosis occurs in the substantia nigra pars compacta (SNc) during rat development, culminating during the perinatal period. We previously showed that lipid peroxidation-mediated oxidative stress is not involved in this cell death process. Nitric oxide (NO) has been proposed to be critical for many developmental processes in brain and has been shown to mediate cell death in neurotoxin models of neurodegenerative disorders. Here, we reported that in vivo pre- and postnatal treatment with the non-specific NO synthase (NOS) inhibitor, L-NAME (60 mg/kg), or with the neuronal NOS inhibitor, 7-NI (30 mg/kg), dramatically decreased the NOS activity as well as the NADPH-diaphorase staining in brain. However, those treatments did not rescue dopamine neurons from developmental death, suggesting that NO is not involved in vivo in developmental death of these neurons or in the overall development of the SNc.