Incidence and predictors of surgical site infection after ORIF in calcaneus fractures, a retrospective cohort study

Pediatric calcaneal osteomyelitis: an analysis of literature-reported 128 cases

BACKGROUND

Calcaneal osteomyelitis (CO) poses a formidable challenge in treatment due to the distinct anatomical structure and functional properties of the calcaneus. The present study endeavors to furnish a thorough and comprehensive understanding of the clinical manifestations, therapeutic strategies, and therapeutic outcomes pertaining to pediatric calcaneal osteomyelitis (PCO) by conducting a meticulous synthesis and analysis of cases reported in the literature.

METHODS

A systematic search of the PubMed, Embase, and Cochrane Library databases was conducted to identify English-language studies analyzing PCO between 2000 and 2021. The quality of the included studies was assessed using the National Institutes of Health (NIH) assessment scale. Effective data were extracted and analyzed.

RESULTS

A total of 42 studies, encompassing 128 patients, fulfilled the established inclusion criteria. The gender distribution revealed a male-to-female ratio of 2:1 (81 boys and 40 girls). The median age at the time of diagnosis was 8 years, while the median duration of symptoms was 0.6 month. Trauma emerged as the primary etiology (41 cases, 54%), and limited activity was the most prevalent symptom (68 cases). The positive rate for pathogen culture was 75.4% (49/65), with Staphylococcus aureus being the most commonly isolated pathogen (28 cases, 57.1%). Surgical intervention was performed in 51% (64/126) of the patients, with debridement serving as the primary surgical strategy. The rate of infection recurrence was 6.8% (8/118), and the risk of below-knee amputation was 0.8% (1/124).

CONCLUSIONS

PCO occurred more frequently in male patients, with trauma being the primary underlying cause and Staphylococcus aureus being the most prevalent bacterial pathogen isolated. Over half of the patients underwent surgical intervention. Nonetheless, it is imperative that treatment strategies undergo further refinement, as approximately 7% of patients experienced infection recurrence.

Intraoperative zero-heat-flux thermometry overestimates nasopharyngeal temperature by 0.39 °C: an observational study in patients undergoing congenital heart surgery

During surgery for congenital heart disease (CHD) temperature management is crucial. Vesical (Tves) and nasopharyngeal (TNPH) temperature are usually measured. Whereas Tves slowly responds to temperature changes, TNPH carries the risk of bleeding. The zero-heat-flux (ZHF) temperature monitoring systems SpotOn™ (TSpotOn), and Tcore™ (Tcore) measure temperature non-invasively. We evaluated accuracy and precision of the non-invasive devices, and of Tves compared to TNPH for estimating temperature. In this prospective observational study in pediatric and adult patients accuracy and precision of TSpotOn, Tcore, and Tves were analyzed using the Bland-Altman method. Proportion of differences (PoD) and Lin´s concordance correlation coefficient (LCC) were calculated. Data of 47 patients resulted in sets of matched measurements: 1073 for TSpotOn vs. TNPH, 874 for Tcore vs. TNPH, and 1102 for Tves vs. TNPH. Accuracy was - 0.39 °C for TSpotOn, -0.09 °C for Tcore, and 0.07 °C for Tves. Precisison was between - 1.12 and 0.35 °C for TSpotOn, -0.88 to 0.71 °C for Tcore, and - 1.90 to 2.05 °C for Tves. PoD ≤ 0.5 °C were 71% for TSpotOn, 71% for Tcore, and 60% for Tves. LCC was 0.9455 for TSpotOn, 0.9510 for Tcore, and 0.9322 for Tves. Temperatures below 25.2 °C (TSpotOn) or 27.1 (Tcore) could not be recorded non-invasively, but only with Tves. Trial registration German Clinical Trials Register, DRKS00010720.

Analysis of risk factors associated with incision complications in modified "L" approach for calcaneal fracture

OBJECTIVE

This study aimed to identify risk factors associated with incision complications following the modified "L" approach for calcaneal fractures.

METHODS

Data from 100 patients treated with the modified "L" approach for calcaneal fractures between January 2018 and December 2021 were analyzed. These included 52 cases in the poorly healing group and 48 in the well-healing group. Variables such as patient age, sex, body mass index, fracture type (Sanders classification), smoking history, alcohol consumption, diabetes status, timing of surgery, tourniquet use, bone grafting, suture method, and postoperative incision care were evaluated. A nomogram was developed using R software to predict the risk of incision complications, validated through the area under the ROC curve, C-index, and decision curve analysis.

RESULTS

Both univariate and multivariate regression analyses identified fracture type, smoking history, diabetes, timing of surgery, and duration of tourniquet application as significant predictors of incision complications. These factors were incorporated into a clinical predictive nomogram. The nomogram's calibration curves demonstrated high accuracy, both internally and externally. The unadjusted concordance indes (C-index) was 0.793 [95% confidence interval (CI), 0.825-0.995], and the area under the curve for the nomogram was 0.7875882. Decision curve analysis confirmed the clinical applicability of the model at a threshold probability of 20-60%.

CONCLUSION

We have developed a reliable clinical nomogram to predict the risk factors for incision complications in the modified "L" approach for calcaneal fractures, enhancing decision-making in clinical settings.

Talus-derived reference coordinate system for 3D calcaneal assessment: A novel approach to improve morphological measurements

In 3D-analysis of the calcaneus, a consistent coordinate system aligned with the original anatomical directions is crucial for pre- and postoperative analysis. This importance stems from the calcaneus's key role in weight-bearing and biomechanical alignment. However, defining a reliable coordinate system based solely on fractured or surgically reconstructed calcanei presents significant challenges. Given its anatomical prominence and consistent orientation, the talus offers a potential solution to this challenge. Our work explores the feasibility of talus-derived coordinate systems for 3D-modeling of the calcaneus across its various conditions. Four methods were tested on nonfractured, fractured and surgically reconstructed calcanei, utilizing Principal Component Analysis, anatomical landmarks, bounding box, and an atlas-based approach. The methods were compared with a self-defined calcaneus reference coordinate system. Additionally, the impact of deviation of the coordinate system on morphological measurements was investigated. Among methods for constructing nonfractured calcanei coordinate systems, the atlas-based method displayed the lowest Root Mean Square value in comparison with the reference coordinate system. For morphological measures like Böhler's Angle and the Critical angle of Gissane, the atlas talus-based system closely aligned with ground truth, yielding differences of 0.6° and 1.2°, respectively, compared to larger deviations seen in other talus-based coordinate systems. In conclusion, all tested methods were feasible for creating a talus derived coordinate system. A talus derived coordinate system showed potential, offering benefits for morphological measurements and clinical scenarios involving fractured and surgically reconstructed calcanei. Further research is recommended to assess the impact of these coordinate systems on surgical planning and outcomes.

Intra-articular Calcaneal Fractures: A Report of Cases and Comments on Preoperative Management

OBJECTIVES

To present a review of the clinical characteristics, preoperative and surgical management, and outcomes of patients with intra-articular calcaneal fractures who had open reduction and internal fixation (ORIF) and to offer some comments on and research ideas for the preoperative management of patients with these fractures.

PATIENTS AND METHODS

We studied consecutive patients who had ORIF performed by a single surgeon for closed, intra-articular calcaneal fractures at our level-1 trauma center between 5/29/2012 and 3/20/2018. All inpatients were treated with a preoperative soft tissue management protocol, whereas outpatients were not. Data were obtained about demographic and clinical characteristics, times from injury to surgery, quality of fracture reductions, and complication rates.

RESULTS

Mean follow-up for the 72 patients with 77 calcaneal fractures was 8.5 (range: 1-43) months, and 21 (27.3%) fractures received inpatient preoperative care with a soft tissue management protocol, while 56 (72.7%) received outpatient preoperative management. More of the fractures treated preoperatively as inpatients versus outpatients were classified as Sanders type III (66.7% vs. 32.1%) and type IV (8.9% vs. 4.8%) fractures and were associated with polytrauma (38.1% vs. 7.1%) and diabetes mellitus (9.5% vs. 5.4%), respectively. For all patients, the mean time from injury to surgery was 12.2 (range: 2.7-19.4) days, and the time was 6.3 days for inpatients and 14.4 days for outpatients, but the quality of fracture reductions and complication rates did not differ between these two groups.

CONCLUSIONS

Patients with intra-articular calcaneal fractures treated as inpatients and receiving a preoperative soft tissue management protocol had outcomes after ORIF that were not inferior to those experienced by patients treated preoperatively as outpatients, despite a greater proportion of the inpatients having severe fractures, polytrauma, and diabetes mellitus. Dedicated preoperative soft tissue management protocols may be beneficial for patients with calcaneal fractures and warrant further study.

Comparison between intramedullary nail and conventional plate for displaced intra-articular calcaneal fractures: A meta-analysis

OBJECTIVES

This study aimed to compare the efficacy and safety of the intramedullary nail and conventional plate for the treatment of displaced intra-articular calcaneal fractures from clinical comparative trials.

MATERIALS AND METHODS

A comprehensive search of English databases was carried out in the Springer, PubMed, ScienceDirect, Web of Science, and Cochrane Library databases until September 2023. Studies on calcaneal fractures treated by an intramedullary nail or a plate were considered for inclusion. Endpoints included duration of operation, length of hospital stay, the Visual Analog Scale (VAS) score, postoperative functional score, radiological parameters, and complications. The mean difference (MD) and risk difference (RD) as the combined variables, as well as the 95% confidence intervals, (CIs) were calculated.

RESULTS

Five retrospective controlled studies covering 473 feet at the one-year follow-up met the inclusion criteria. The meta-analysis demonstrated that there were significant differences in the duration of operation (MD: -10.81; 95% CI: -16.32, -5.31; p=0.0001), length of hospital stay (MD: -3.65; 95% CI: -4.35, -2.95; p<0.00001). No significant differences were found regarding postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale (MD: 0.36; 95% CI: -3.89, 4.61; p=0.87), VAS (MD: 1.95; 95% CI: -0.30, 4.21; p=0.09), or postoperative Böhler angle (MD: 0.94; 95% CI: -0.04, 1.92; p=0.06) between the two groups. The incidence of total complications (RD: -0.31; 95% CI: -0.46, -0.17; p<0.0001) and wound-healing complications (RD: -0.16; 95% CI: -0.30, -0.03; p=0.02) were lower in the intramedullary nail group. There were no significant differences in the incidences of revision surgery, implant removal, superficial wound infection, deep infection, and nonunion.

CONCLUSION

Compared to conventional plates, the intramedullary nail showed a shorter duration of operation, reduced length of hospital stay, and fewer postoperative total complications and wound-healing complications in treating displaced intra-articular calcaneal fractures.

Prevalence of surgical site infection and risk factors in patients after knee surgery: A systematic review and meta-analysis

The present systematic review and meta-analysis aimed to determine the prevalence of surgical site infection (SSI) and risk factors in patients after knee surgery. A comprehensive and systematic search was carried out across various international electronic databases, including Scopus, PubMed and Web of Science, as well as Persian electronic databases like Iranmedex and the Scientific Information Database (SID). This search involved the utilization of keywords derived from Medical Subject Headings, such as 'Prevalence', 'Surgical wound infection', 'Surgical site infection' and 'Orthopaedics', spanning from the earliest records up to 1 October 2023. To assess the quality of the included studies, the Appraisal tool for Cross-Sectional Studies (AXIS tool) was utilized. The study encompassed a combined participant pool of 11 028 individuals who underwent knee surgery across seven selected studies. The collective prevalence of SSI in patients who underwent knee surgery, as reported in the seven included studies, was determined to be 3.0% (95% CI: 1.2% to 7.5%; I2  = 96.612%; p < 0.001). The combined prevalence of SSI in patients with DM, as reported in six studies, was 5.1% (95% CI: 1.7% to 14.5%; I2  = 79.054%; p < 0.001). Similarly, the pooled prevalence of SSI in patients with HTN, drawn from four studies, was 1.8% (95% CI: 0.7% to 4.5%; I2  = 63.996%; p = 0.040). Additionally, the collective prevalence of SSI in patients with a history of tobacco use, based on findings from six studies, was 4.8% (95% CI: 1.4% to 15.2%; I2  = 93.358%; p < 0.001). Subgroup analysis was conducted within six studies, categorizing them by two countries, namely China and the USA. These analyses revealed that the prevalence of SSI following knee surgery was 3.0% in China and 2.0% in the USA. It is noteworthy that variations in SSI prevalence across different studies may be attributed to a multitude of factors, particularly varying risk factors among patient populations. To address this issue and mitigate the impact of SSI on knee surgery patients, it is advisable to develop tailored interventions.

Prevalence of surgical site infection and risk factors in patients after foot and ankle surgery: A systematic review and meta-analysis

The present systematic review and meta-analysis aimed to determine the prevalence of surgical site infection (SSI) and related factors in patients after foot and ankle surgery. A comprehensive, systematic search was conducted in different international electronic databases, such as Scopus, PubMed, Web of Science and Persian electronic databases such as Iranmedex and Scientific Information Database (SID) using keywords extracted from Medical Subject Headings such as 'Prevalence', 'Surgical wound infection', 'Surgical site infection' and 'Orthopaedics' from the earliest to 1 June 2023. The appraisal tool for cross-sectional studies (AXIS tool) evaluates the quality of the included studies. A total of 10 447 patients undergoing foot and ankle surgery participated in nine studies. The pooled prevalence of SSI in patients who underwent foot and ankle surgery was reported in nine studies was 4.2% (95% CI: 2.4%-7.2%; I2  = 96.793%; p < 0.001). The odds ratio of SSI prevalence in men was higher than that of women and was significant (OR: 1.335; 95% CI: 1.106-1.612; Z = 3.009; p = 0.003). The pooled prevalence of SSI in patients with hindfoot fracture sites reported in five studies was 4.9% (95% CI: 2.6%-8.9%; I2  = 90.768%; p < 0.001). The pooled prevalence of SSI in patients with diabetes mellitus (DM) reported in six studies was 9.1% (95% CI: 5.6%-14.6%; I2  = 73.957%; p = 0.002). The pooled prevalence of SSI in patients with hypertension (HTN) reported in five studies was 5.5% (95% CI: 2.5%-11.6%; I2  = 91.346%; p < 0.001). The pooled prevalence of SSI in patients with tobacco use reported in eight studies was 6.6% (95% CI: 4.1%-10.4%; I2  = 85.379%; p < 0.001). In general, the existing differences in the prevalence of SSI after foot and ankle surgery in different studies can be based on different risk factors such as comorbidities and gender. Therefore, it is suggested to design appropriate interventions to reduce SSI in these patients.

Factors Contributing to Surgical Site Infections: A Comprehensive Systematic Review of Etiology and Risk Factors

Surgical site infections persist as a substantial concern within the realm of hospital-acquired infections. This enduring issue is further compounded by the mounting challenge of antibiotic resistance, a surge in surgical interventions, and the presence of comorbidities among patients. Thus, a comprehensive exploration of all discernible risk factors, as well as proactive preventive and prophylactic strategies, becomes imperative. Moreover, the prevalence of multidrug-resistant microorganisms has reached alarming proportions. Consequently, there is an acute need to investigate and scrutinize all potential therapeutic interventions to counter this burgeoning threat. Consequently, the primary objective of this review is to meticulously assess the origins and risk elements intertwined with surgical site infections across a diverse spectrum of surgical procedures. As the medical landscape continues to evolve, this critical analysis seeks to provide a nuanced understanding of the multi-faceted factors contributing to surgical site infections, with the overarching aim of facilitating more effective management and mitigation strategies. By exploring these dimensions comprehensively, we endeavor to enhance patient safety and the quality of surgical care in this era of evolving healthcare challenges.

The role of preoperative glycemic control in decreasing surgical site infections in lower extremity fractures

BACKGROUND

Postoperative surgical site infections (SSIs) are an important complication to prevent in surgical treatment. Patients with diabetes mellitus (DM) have a higher risk of SSIs. Preoperative glycemic control is required. For patients with orthopedic trauma, the duration of preoperative glycemic control is limited because delaying operative treatment is difficult. However, whether preoperative glycemic control would decrease the risk of SSIs in diabetic patients with lower extremity fractures is unclear. The first aim of this study was to investigate the rate of SSIs among patients with DM who had undergone preoperative glycemic control, compared with that of patients without DM. As the secondary aim, we sought to demonstrate among patients with DM whether preoperative glycemic control would affect the development of SSIs between patients with controlled DM and patients with poorly controlled DM.

METHODS

In this retrospective cohort study, 1510 patients treated surgically for lower extremity fractures were enrolled. Data collected were patient age, sex, body mass index, history of DM, development of SSIs, tobacco use, the presence of an open fracture, the period between the day of injury and the operation, the length of surgery, and blood glucose levels on admission and on the day before surgery.

RESULTS

The rate of total SSIs was 6.0% among patients with DM and 4.4% among patients without DM (p = 0.31). Multivariate logistic regression revealed a significant association between the development of SSIs and the presence of DM (odds ratio, 1.79; 95% confidence interval 1.01-3.19; p = 0.047). The results of the secondary study revealed that the rate of early SSIs was significantly higher in the poorly controlled DM group than in the controlled DM group (5.9% vs. 1.5%; p = 0.032). However, multivariate logistic regression revealed that control levels of DM were not significantly associated with the development of SSIs.

CONCLUSIONS

Even though patients with DM had undergone preoperative glycemic control, SSIs were significantly associated with DM, especially when the patients had poorly controlled DM. This finding suggested that continuous glycemic control is important preoperatively and postoperatively to prevent SSIs.

Clinical outcomes following treatment of deep surgical site infection after fixation of calcaneal fractures: A retrospective case-control study

INTRODUCTION

Deep surgical site infection (SSI) may be a complication of open reduction and internal fixation (ORIF) of calcaneal fractures. This study aimed to describe the characteristics of patients with deep SSI following ORIF of calcaneal fractures via extensile lateral approach (ELA). We compared clinical outcomes of these patients, with a minimum follow-up of one year after successful treatment of deep SSI with a matched control group.

METHODS

In this retrospective case-control study, demographic data, fracture characteristics, bacterial pathogens, medical treatments and surgical approaches were collected, also the outcome was evaluated by the visual analog scale (VAS) for pain, foot function index (FFI) and AOFAS ankle-hindfoot score. The differences in Böhler and Gissane's angles between infected and contralateral feet were measured. By matching a control group of uninfected cases, clinical outcomes were compared between 2 groups using the Mann-Whitney U test.

RESULTS

Among 331 calcaneus fractures in 308 patients (mean age, 38.0 ± 13.1; male/female ratio, 5.5), 21 had deep SSI (6.3 %). There were 16 (76.2 %) males and 5 (23.8 %) females with a mean age of 35.1 ± 11.7 years. Thirteen (61.9 %) patients had unilateral fractures. The most common Sanders Type was found to be type II. The most frequent type of detected microorganisms was Staphylococcus species. Intravenous antibiotic therapy, mostly clindamycin, imipenem and vancomycin, based on the microbiological results, was prescribed with a mean±SD duration of 28.1 ± 16.5 days. The mean number of surgical debridements was 1.8 ± 1.3. Implants needed to be removed in 16 (76.2 %) cases. Antibiotic-impregnated bone cement was applied in three (14.3 %) cases. The clinical outcomes of 15 cases (follow up, 35.5 ± 13.8; range, 12.6-64.5 months) were 4.1 ± 2.0, 16.7 ± 12.3 and 77.5 ± 20.8 for VAS for pain, FFI % and AOFAS ankle-hindfoot score, respectively. Comparing with the control group (VAS for pain, 2.3 ± 2.7; FFI %, 12.2 ± 16.6, and AOFAS, 84.6 ± 18.0), only VAS pain was statistically lower in this group (p-value: 0.012). The differences in Böhler and Gissane's angles between both feet of infected cases were - 14.3 ± 17.9 and - 7.7 ± 22.5 (worse in the infected side), respectively.

CONCLUSION

Proper on-time approaches to deep infection following ORIF of calcaneal fractures may lead to acceptable clinical and functional outcomes. Sometimes aggressive approaches with intravenous antibiotic therapy, multiple sessions of surgical debridement, removal of implants and antibiotic impregnated cement are necessary to eradicate deep infection.

LEVEL OF EVIDENCE

Level III.

Evaluation of the Temple Touch Pro™ noninvasive core-temperature monitoring system in 100 adults under general anesthesia: a prospective comparison with esophageal temperature

Perioperative hypothermia is still common and has relevant complication for the patient. An effective perioperative thermal management requires essentially an accurate method to measure core temperature. So far, only one study has investigated the new Temple Touch Pro™ (Medisim Ltd., Beit-Shemesh, Israel). during anesthesia Therefore, we assessed the agreement between the Temple Touch Pro™ thermometer (TTP) and distal esophageal temperature (T_Eso) in a second study. After approval by the local ethics committee we studied 100 adult patients undergoing surgery with general anesthesia. Before induction of anesthesia the TTP sensor unit was attached to the skin above the temporal artery. After induction of anesthesia an esophageal temperature probe was placed in the distal esophagus. Recordings started 10 min after placement of the esophageal temperature probe to allow adequate warming of the probes. Pairs of temperature values were documented in five-minute intervals until emergence of anesthesia. Accuracy of the two methods was assessed by Bland-Altman comparisons of differences with multiple measurements. Core temperatures obtained with the TTP in adults showed a mean bias of -0.04 °C with 95% limits of agreement within - 0.99 °C to + 0.91 °C compared to an esophageal temperature probe. We consider the TTP as a reasonable tool for perioperative temperature monitoring. It is not accurate enough to be used as a reference method in scientific studies, but may be a useful tool especially for conscious patients undergoing neuraxial anesthesia or regional anesthesia with sedation. Trial registration This study was registered in the German Clinical Trials Register (DRKS-ID: 00024050), day of registration 12/01/2021.

Global research trends and hotspots in calcaneal fracture: A bibliometric analysis (2000-2021)

Background

Calcaneal fracture is common and carries high morbidity and disability. Its treatment is therefore of vital concern. Many topics concerning calcaneal fracture remain controversial, and the subject has not yet been well-researched. We aim to analyze and illustrate the trends in development, overall knowledge structure, "hotspots," and research frontiers on the topic of calcaneal fracture.

Methods

Literature relating to calcaneal fracture published between 2000 and 2021 was retrieved from Science Citation Index Expanded (SCIE) database of the Web of Science. Three bibliometric tools (Bibliometrix, CiteSpace, and VOSviewer software) were used for analysis and the generation of knowledge maps. Annual trends in publication counts and the relative contributions of different countries, regions, institutions, authors, and journals, as well as keyword clusters, "hot topics," and research frontiers, were analyzed.

Results

A total of 1,687 publications were included in the analysis. The number of calcaneal fracture articles published worldwide each year was highest in 2019, with a total of 128 articles. The United States has made the greatest contribution to the field, with the largest number of publications and the highest H-index. Foot & Ankle International was the most productive journal, publishing a total of 167 articles on calcaneal fracture during the study period. Hebei Medical University of China and the University of California, San Francisco were the most prolific institutions. Professors T. Schepers, S. Rammelt, H. Zwipp, and Y. Z. Zhang have made remarkable contributions to the field. However, the degree of collaboration between researchers and among institutions was relatively low, and took place mainly in Europe and the Americas. All relevant keywords could be categorized into three clusters: studies of internal fixation, studies of fractures, and studies of osteoporosis. A trend of balanced and diversified development could be seen within these clusters. Keywords with ongoing "citation bursts," such as sinus tarsi approach, wound complications, minimally invasive technique, extensile lateral approach, surgical treatment, and plate, may continue to be research "hotspots" in the near future.

Conclusion

Based on current global trends, the number of publications on calcaneal fracture will continue to increase. Topics such as minimally invasive techniques and complications have become important hotspots of research. We recommend enhancing international communication and collaboration for future research in this field.

Current Concepts of Fracture-Related Infection

Currently, fracture-related infection (FRI) still represents great challenges in front of orthopaedic surgeons, despite great advances that have been achieved regarding its diagnosis and treatment. Although both FRI and prosthetic joint infection (PJI) belong to osteoarticular infections and share similarities, FRI displays unique characteristics. Diagnosis of FRI is sometimes difficult owing to the nonspecific symptoms, and treatment is usually tricky, with a high risk of infection recurrence. In addition, the long disease course is associated with a significantly elevated risk of disability, both physically and psychologically. Moreover, such a disorder still poses heavy economic burdens to the patients, both personally and socially. Therefore, early diagnosis and reasonable treatment are the key issues for increasing the cure rate, decreasing the risks of infection relapse and disability, and improving the life quality and prognosis of the patients. In this review, we summarized the present concepts regarding the definition, epidemiology, diagnosis, and treatment of FRI.

Risk factor of postoperative incision infection after plate internal fixation of calcaneal fractures: a retrospective study

BACKGROUND

This study aimed to investigate the risk factors for incision infection after plate internal fixation for calcaneal fractures by a traditional lateral L-shaped approach.

METHODS

The clinical data of 302 patients with calcaneal fractures who underwent surgical treatment in our hospital from January 2012 to June 2018 were retrospectively analysed, consisting of 177 males and 125 females. The enrolled patients were aged 21 to 75 years, with a mean age of 47.72 years. According to the Sanders classification, 108 patients were type II, 138 patients were type III, and 56 cases were type IV. A univariate analysis was conducted with sex, age, smoking history, history of diabetes, cause of injury, Sanders type, tension blisters, time from injury to surgery, preoperative haemoglobin, preoperative albumin, operation time, and bone grafting as possible risk factors. The factors with statistically significant differences were selected for multivariate binary logistic regression analysis. The clinical cut-off values of these risk factors were calculated using characteristic curves.

RESULTS

The follow-up lasted for at least 1 year for all patients, with a mean follow-up time of 15.8 months. The results demonstrated 7.9% (24/302) infection rate after plate internal fixation of calcaneal fractures by the traditional lateral L-shaped approach. Univariate analysis showed that a history of diabetes, preoperative albumin, preoperative haemoglobin, time from injury to surgery, and operation time were correlated with incision infection (p < 0.05). Additionally, multivariate regression analysis indicated that a shorter time from injury to surgery (OR = 1.475, 95% CI: 1.024-2.125, p = 0.037), lower preoperative albumin (OR = 1.559, 95% CI: 1.191-2.041, p = 0.001), and longer operation time (OR = 1.511, 95% CI: 1.219-1.874, p < 0.001) were risk factors for postoperative incision infection, and their cut-off values were 10.5 days, 38.5 g/L, and 84.5 minutes, respectively.

CONCLUSION

Longer preoperative stay and operation time were two risk factors for postoperative incision infection. However, lower preoperative albumin level is the highest risk factor in this study.

TRIAL REGISTRATION

The trial was registered in the China Clinical Trial Registry (ChiCTR2100047038).

Technique and Early Outcomes for High-Energy Calcaneus Fractures Treated With Staged External Fixation to Combined Open Reduction Internal Fixation and Subtalar Arthrodesis

OBJECTIVE

(1) To present an effective surgical technique for the treatment of open and high-energy calcaneal fractures with significant soft tissue injuries. (2) To present complications with this technique and to evaluate patient-reported outcomes of staged external fixation followed by delayed reconstruction with open reduction internal fixation (ORIF) and subtalar arthrodesis.

DESIGN

Retrospective case series.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

Twelve patients with 13 calcaneus fractures associated with open traumatic wounds (10 patients) or other severe soft tissue injury (ie, fracture blisters) between April 2013 and December 2019.

INTERVENTION

All patients were treated with staged ankle-spanning external fixation and delayed reconstruction with ORIF with subtalar arthrodesis.

MAIN OUTCOME MEASURES

Patient-Reported Outcomes Measurement Information System (PROMIS) outcomes are presented via the domains of physical function (PF), pain interference (PI), and depression (D) in addition to visual analog score. Complications with the injury and surgical procedure were reported as well.

RESULTS

Patients underwent initial stabilization on average 1.3 days (range, 0-12 days) from injury with stage II occurring on average 31.1 days (range, 18-42 days) from external fixation. Mean time to radiographic union was 5.6 months (range, 4-10 months). One-year mean PROMIS outcomes were as follows: PF final average of 37.4 with an average improvement of 12.2 (P < 0.01), PI final average of 62.2 with average improvement of 5.6 (P = 0.01), and D final average of 52.1 with average improvement of 6 (P = 0.12). Mean final visual analog score pain score was 3.6 with an average improvement of 2.25 (P = 0.01).

CONCLUSION

Staged treatment with initial external fixation followed by ORIF and subtalar arthrodesis in the setting of highly comminuted calcaneus fractures with significant soft tissue compromise effectively addresses both bony and soft tissue concerns while providing for positive outcomes postoperatively with regards to pain and function. There were minimal complications noted for this complex injury.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Development of a nomogram to predict surgical site infection after closed comminuted calcaneal fracture

Background

Compared with open comminuted calcaneal fractures, less emphasis is placed on postoperative surgical site infection (SSI) of closed comminuted calcaneal fractures. This study aimed to identify the risk factors associated with SSI and build a nomogram model to visualize the risk factors for postoperative SSI.

Methods

We retrospectively collected patients with closed comminuted calcaneal fractures from the Second Affiliated Hospital of Wenzhou Medical University database from 2017 to 2020. Risk factors were identified by logistics regression analysis, and the predictive value of risk factors was evaluated by ROC (receiver operating characteristic curve). Besides, the final risk factors were incorporated into R4.1.2 software to establish a visual nomogram prediction model.

Results

The high-fall injury, operative time, prealbumin, aspartate aminotransferase (AST), and cystatin-C were independent predictors of SSI in calcaneal fracture patients, with OR values of 5.565 (95%CI 2.220–13.951), 1.044 (95%CI 1.023–1.064), 0.988 (95%CI 0.980–0.995), 1.035 (95%CI 1.004–1.067) and 0.010 (95%CI 0.001–0.185) (P_s < 0.05). Furthermore, ROC curve analysis showed that the AUC values of high-fall injury, operation time, prealbumin, AST, cystatin-C, and their composite indicator for predicting SSI were 0.680 (95%CI 0.593–0.766), 0.756 (95%CI 0.672–939), 0.331 (95%CI 0.243–0.419), 0.605 (95%CI 0.512–0.698), 0.319 (95%CI 0.226–0.413) and 0.860 (95%CI 0.794–0.926), respectively (P_s < 0.05). Moreover, the accuracy of the nomogram to predict SSI risk was 0.860.

Conclusions

Our study findings suggest that clinicians should pay more attention to the preoperative prealbumin, AST, cystatin C, high-fall injury, and operative time for patients with closed comminuting calcaneal fractures to avoid the occurrence of postoperative SSI. Furthermore, our established nomogram to assess the risk of SSI in calcaneal fracture patients yielded good accuracy and can assist clinicians in taking appropriate measures to prevent SSI.

Risk Factors for Infection Following Operative Treatment of Traumatic Upper Extremity Amputation Injury

Background: Identification of the risk factors for surgical site infection (SSI) can be a straightforward and cost-effective measure to reduce or prevent the occurrence of SSI. However, there are no studies that revealed risk factors for SSI for traumatic upper extremity amputation. The aim of this study is to investigate the risk factors that promote SSI after surgery for traumatic upper extremity amputation using a large nationwide database.

Methods: We used data from the Japan Trauma Data Bank. Diagnoses were defined using the Abbreviated Injury Scale code. We applied multivariate logistic regression to evaluate the infection risk factor. We chose age, sex, vital signs, cause and type of trauma, concomitant injury, diabetes, amputation level, Glasgow coma scale, Injury Severity Score (ISS) and blood transfusion within 24 hours following hospital arrival as confounders. Receiver operating characteristic (ROC) curve analysis was adopted to identify thresholds for change in infection risk. We also applied propensity score (PS) matching to adjust for confounding factors that may affect the outcome.

Results: A total of 1,150 patients (967 males, 183 females) had traumatic upper extremity amputation. The mean patient age was 46.5 years. A total of 21 patients (1.8%) suffered from SSI. ISS, blood transfusion, systolic blood pressure (BP) and the upper extremity amputation except for finger were identified as the independent significant risk factors for SSI occurrence by the multivariate analysis (p < 0.05, p < 0.005, p < 0.05 and p < 0.005, respectively). ROC modelling revealed that patients with ISS of over 9 or systolic BP of over 160 had a risk for SSI. After PS matching, the patients with blood transfusion or systolic BP of over 160 had a significantly higher risk of infection (OR 9.0; p = 0.01 and OR 7.0; p = 0.03, respectively).

Conclusions: In treating patients with these risk factors, we must be especially careful in performing thorough debridement and wound care.

Level of Evidence: Level II (Therapeutic)

A nomogram for predicting post-operative wound complications after open reduction and internal fixation for calcaneal fractures

The purpose of our study was to determine the risk factors for post-operative wound complications (PWCs) after open reduction and internal fixation (ORIF) for calcaneal fracture and establish a nomogram prediction model. We retrospectively analysed the clinical data of patients who suffered from calcaneal fractures and had been surgically treated for ORIF in our institution between January 2010 and January 2020. Perioperative information was obtained through the electronic medical record system, univariate and multivariate analyses were performed to determine the risk factors of PWCs, and a nomogram model was constructed to predict the risk of PWCs. The predictive performance and consistency of the model were evaluated by the Hosmer -Lemeshow (H-L) test and the calibration curve. In total, 444 patients were enrolled in our study. Multivariate analysis results showed that smoking, limb swelling, angle of incision, and CRP were independent risk factors for skin necrosis. The AUC value for skin necrosis risk was 0.982 (95%CI 0.97-0.99). The H-L test revealed that the normogram prediction model had good calibration ability (P = .957). Finally, we found a correlation between PWCs and smoking, limb swelling, angle of incision, and CRP after ORIF for calcaneal fracture patients. Our nomogram prediction model might be helpful for clinicians to identify high-risk patients, as interventions could be taken early to reduce the incidence of PWCs.

Anatomical parameters of sustentaculum Tali screw placement in the Asian population: A retrospective radio-anatomical study

Purpose: This study aimed to determine the anatomical parameters of successful Sustentaculum Tali (ST) screw placement in the Asian population. Method: CT scans of unilateral feet of 110 participants were reviewed, retrospectively. The 3 D reconstruction of the calcaneus and morphometric measurements were performed by Mimics Research 19.0 and 3-Matic Research 11.0. Finally, six cadaveric feet were used for verification of the accuracy of the measurements. Results: We discovered a method to help place ST screw successfully: (1) The entry point located at the middle section of the lateral wall of posterior talar articular surface (PTAS), and the perpendicular distance from the entry point to the lateral edge of PTAS (PDEL) was 10.78 mm, (2) Screw was perpendicular to the z-axis, 66.98° to the y-axis (the longitudinal axis of the foot), (3) The length of the ST screw should be approximately 44.74 mm in male and 41.14 mm in female, and (4) The diameter of the ST screw should be approximately 4.0 mm in male and 3.5 mm in female. With this new method, all screws in six cadaveric feet were placed successfully into the middle of ST. Conclusions: In this study, we discovered a general approach to safely place ST screws in the Asian population, which may potentially help surgeons improve their success rate in surgical practice.

Risk Factors for Gram-Negative Fracture-Related Infection

In this study, we evaluated risk factors for gram-negative fracture-related infection in a mixed cohort of gram-positive and gram-negative fracture-related infections to guide perioperative antibiotic prophylaxis for surgical fixation of fractures. We performed a retrospective review of all patients with fracture who were treated at an urban academic level I trauma center between February 1, 2012, and June 30, 2017. Inclusion criteria were as follows: (1) open or closed fracture with internal fixation; (2) deep, acute to subacute (<6 weeks), culture-positive fracture-related infection; and (3) age 18 years or older. Infections were classified as gram positive, gram negative, or polymicrobial. Demographic, surgical, and postoperative characteristics were compared among groups. Of 3360 patients, 43 (1.3%) had a fracture-related infection (15 gram negative, 14 gram positive, and 14 polymicrobial). Risk factors for gram-negative infection included initial external fixation (P=.038), the need for soft tissue coverage of an open fracture site (P=.039), lower albumin level at the time of infection (P=.005), and hospitalization for longer than 10 days (P=.018). Perioperative gram-negative antibiotic prophylaxis for fracture fixation surgery should be considered for those who have been staged with external fixation, require soft tissue coverage, are at risk for malnutrition in the postoperative period, and have prolonged inpatient hospitalization. [Orthopedics. 2022;45(2):91-96.].

Predictors for wound healing complications and prolonged hospital stay in patients with isolated calcaneal fractures

Purpose

Surgically treated calcaneal fractures have a high risk of postoperative wound healing complications and a prolonged length of hospital stay (LOS). The aim of this study was to identify predictor variables of impaired wound healing (IWH) and LOS in surgically treated patients with isolated calcaneal fractures.

Methods

This retrospective cohort study analyzed data on patients aged 18 years or older who were admitted to a level I trauma center with isolated calcaneal fractures between 2008 and 2018. Multivariable regression models were used to identify predictor variables.

Results

In total, 89 patients (age: 45.4 years; SD: 15.1) were included. In 68 of these patients, low-profile locking plate osteosynthesis was performed, and a minimally invasive approach (MIA) (percutaneous single screws/K-wire or low-profile locking plating via a sinus tarsi approach) was applied in 21 patients. Multivariable regression analysis revealed that a higher preoperative Böhler’s angle (β = − 0.16 days/degree, 95% CI [− 0.25, − 0.08], p = 0.004) and MIA (β = − 5.04 days, 95% CI [− 8.52, − 1.56], p = 0.002) reduced the LOS. A longer time-to-surgery (β = 1.04 days/days, 95% CI [0.66, 1.42] p = 0.001) and IWH increased the LOS (β = 7.80 days, 95% CI [4.48, 11.12], p = 0.008). In a subsequent multivariable regression analysis, two variables, open fractures (OR: 14.6, 95% CI [1.19, 180.2], p = 0.030) and overweight (BMI > 24) (OR: 3.65, 95% CI [1.11, 12.00], p = 0.019), increased the risk of IWH.

Conclusion

Advanced treatment algorithms for open fractures are needed to reduce the risk of IWH.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-021-01863-1.

The arthroscopic minimally-invasive technique improves the clinical symptoms and facilitates the functional recovery of the lower limbs in knee joint bone trauma patients

OBJECTIVE

This study aims to demonstrate the effect of the arthroscopic minimally invasive technique on the clinical symptoms and lower limb functional recovery in knee joint bone trauma patients.

METHODS

From January 2015 to January 2020, 150 knee joint bone trauma patients were recruited as the study cohort and divided into two groups according to the different intervention method each patient underwent. The patients in the control group (the CG, n=68) were administered routine treatment, and the patients in the research group (the RG, n=82) were treated using the arthroscopic minimally invasive technique. The postoperative clinical operative indexes and the clinical effectiveness, as well as the intraoperative complications were observed in the two groups. The inflammatory factor levels before and after the surgeries were compared. The Visual Analogue Scale (VAS) was employed to evaluate the pain levels before and after the surgeries, the Hospital for Special Surgery Knee Scores (HSS) were used to assess the knee joint recoveries before and at six months after the operations, and the Fugl-Meyer Assessment Scale (FMAS) was used to determine the lower limb functional recovery before and at six months after the operations.

RESULTS

The RG had significantly shorter operation times, lower intraoperative blood losses, shorter average ambulation times, shorter hospital stays, shorter fracture healing times, and smaller incisions than the CG. Postoperatively, the IL-8 and TNF-α levels were significantly lower in the RG than in the CG. The RG exhibited observably lower VAS scores after the operations, as well as evidently higher HSS scores and FMAS scores at six months postoperatively than the CG. In comparison with the CG, the RG had a significantly higher total effective rate and a noticeably lower incidence of postoperative complications.

CONCLUSIONS

The arthroscopic minimally invasive technique is effective at treating patients with knee joint bone trauma, and it can promote the surgical recovery of patients and facilitate the functional recovery of the knee joint and the lower limbs.

Relationship between surgeon volume and the risk of deep surgical site infection (DSSI) following open reduction and internal fixation of displaced intra-articular calcaneal fracture

It is well established that the postoperative results were affected by the surgeon volume in a variety of elective and emergent orthopaedic surgeries; however, by far, no evidences have been available as for surgically treated displaced intra-articular calcaneal fractures (DIACFs). We aimed at investigating the relationship between surgeon volume and deep surgical site infection (DSSI) following open reduction and internal fixation (ORIF) of DIACFs. This was a further analysis of prospectively collected data from a validated database. Patients with DIACFs stabilised by ORIF between 2016 and 2019 were identified. Surgeon volume was defined as the number of surgically treated calcaneal fractures within one calendar year and was dichotomised based on the optimal cut-off value. The outcome measure was DSSI within 1 year postoperatively. Multivariate logistics regression analyses were performed to examine the relationship, adjusting for confounders. Among 883 patients, 19 (2.2%) were found to have a DSSI. The DSSI incidence was 6.5% in surgeons with a low volume (<6/year), 5.5 times as that in those with a high volume (≥6/year) (incidence rate, 1.2%; P < 0.001). The multivariate analyses showed a low volume <6/year was associated with a 5.8-fold increased risk of DSSI (95% confidence interval, 2.2-16.5, P < 0.001). This value slightly increased after multiple sensitivity analyses, with statistical significances still unchanged (OR range, 6.6-6.9; P ≤ 0.001). The inverse relationship indicates a need for at least six cases/year for a surgeon to substantially reduce the DSSIs following the ORIF of DIACFs.

Survival at 30 days in elderly patients with hip fracture surgery who were exposed to hypothermia: Survival study

The effect of hypothermia as a mortality risk factor at 30 days in the elderly who had hip fracture (HF) surgery is still controversial because it may be due to a set of poorly identified factors. In this study, we aim to determine if exposure to intra and immediate postoperative hypothermia increases the incidence of mortality at 30 days in elderly patients who had HF surgery.Survival study in the elderly who had HF surgery with and without exposure to hypothermia. Sociodemographic, anesthetic and surgical factors were collected. The temperature of the rectum was measured at the end of the surgery and in the recovery room. The effect of hypothermia was analyzed by the incidence of mortality at 30 days. Other results were considered, such as, surgical site infection (SSI), blood transfusions, and influence of implants used in the 30-day mortality.Three hundred eighty five subjects were eligible, to include 300. Inadvertent hypothermia was 12%, the 30-day overall mortality was 9% and in subjects with hypothermia it was 25% (P = .002). Subjects with hypothermia had a higher risk of SSI (relative risk 4.2, 95% confidence interval 1.3-13.6, P = .03) and receive more transfusions (relative risk 3.6, 95% confidence interval 2.0-6.5, P < .001).Elderly subjects with HF exposed to hypothermia who undergo hip hemiarthroplasty and who receive 2 or more blood transfusions during their treatment, are at greater risk of dying after 30 days of the surgery. Hypothermia, as a possible causative factor of mortality, should continue to be studied.

Epidemiology and microbiology of fracture-related infection: a multicenter study in Northeast China

Objective

This study aimed to explore the epidemiological and microbiological characteristics of fracture-related infection (FRI), analyze the drug resistance characteristics of major pathogens, and provide timely and relatively complete clinical and microbiological data for antimicrobial treatment of FRI.

Methods

The clinical and microbiological data of patients with FRI from January 1, 2011, to December 31, 2020, were collected from three tertiary hospitals in Northeast China. The automatic microbial analysis system was used for strain identification and drug susceptibility testing, and the drug susceptibility results were determined in accordance with the latest Clinical and Laboratory Standards Institute (CLSI) criteria (as applicable each year).

Results

A total of 744 patients with FRI were enrolled. The incidence of FRI was about 1.5%, and 81.7% were male patients, with an average age of 48.98 ± 16.01 years. Open fractures accounted for 64.8%. Motor crush (32.8%) and falling (29.8%) were the main causes of injuries. The common sites of infection were the tibia and fibula (47.6%), femur (11.8%), foot (11.8%), and hand (11.6%). A total of 566 pathogenic bacteria were cultured in 378 patients with positive bacterial cultures, of which 53.0% were Gram-positive bacteria and 47.0% were Gram-negative bacteria. The most common pathogen at all sites of infection is Staphylococcus aureus. Staphylococcus aureus had a high resistance rate to penicillin (PEN), erythromycin (ERY), and clindamycin (CLI), exceeding 50%. Methicillin-resistant Staphylococcus aureus (MRSA) was more than 80% resistant to CLI and ERY.

Conclusions

The incidence of FRI in Northeast China was at a low level among major medical centers nationwide. Staphylococcus aureus was still the main pathogen causing bone infections, and the proportion of MRSA was lower than reported abroad, but we have observed an increase in the proportion of infections. Enterobacteriaceae have a higher resistance rate to third-generation cephalosporins and quinolones. For Enterobacteriaceae, other sensitive treatment drugs should be selected clinically.

Risk prediction model for deep surgical site infection (DSSI) following open reduction and internal fixation of displaced intra-articular calcaneal fracture

Deep surgical site infection (DSSI) is a serious complication affecting the surgical outcome of displaced intra‐articular calcaneal fracture, and a risk prediction model based on the identifiable risk factors will provide great clinical value in prevention and prompt interventions. This study retrospectively identified patients operated for calcaneal fracture between January 2014 and December 2019, with a follow‐up ≥1 year. The data were extracted from electronic medical records, with regard to demographics, comorbidities, injury, surgery and laboratory biomarkers at admission. Univariate and multivariate logistics regression analyses were used to identify the independent factors for DSSI, thereby the risk prediction model was developed. Among 900 patients included, 2.7% developed a DSSI. The multivariate analyses identified five factors independently associated with DSSI, including current smoking (OR, 2.8; 95% confidence interval [CI], 1.3‐6.4; P = .021), BMI ≥ 26.4 kg/m² (OR, 3.1; 95% CI, 1.6‐8.4; P = .003), ASA ≥II (OR, 1.3; 95% CI, 1.0‐5.1; P = .043), incision level of II (OR, 3.8; 95% CI, 1.3‐12.6; P = .018) and NLR ≥6.4 (OR, 3.2; 95% CI, 1.3‐7.5; P = .008). A score of 14 as the optimal cut‐off value was corresponding to sensitivity of 0.542 and specificity of 0.872 (area, 0.766; P < .001); ≥14 was associated with 8.1‐times increased risk of DSSI; a score of 7 was corresponding sensitivity of 100% and 10 corresponding to sensitivity of 0.875. The risk prediction model exhibited excellent performance in distinguishing the risk of DSSI and could be considered in practice for improvement of wound management, but its validity requires to be verified by better‐design studies.

Outcome of Minimally Invasive Osteosynthesis for Displaced Intra-articular Calcaneal Fractures Using Cannulated Screws: A Prospective Case Series

This prospective study sought to assess the functional and radiological outcomes of minimally invasive osteosynthesis using cannulated screws and to examine the effect of different parameters on the functional outcome. The Maryland foot score and the visual analog scale of pain were used to assess the functional outcomes and postoperative patient's satisfaction rate. Preoperative and postoperative Böhler's angle, angle of Gissane, calcaneal width, and height, were compared. The study included 46 fractures in 40 patients; 38 (95%) males and 2 (5%) females with a mean age of 34.8 ± 3 years. The mean time lapse to surgery was 3.2 ± 2.1 days. The mean duration of surgery was 39.8 ± 9.3 minutes. The mean follow-up period was 29.2 months. At final follow-up, the mean Maryland foot score was 85 ± 6.3. Satisfactory results were achieved in 91.3% of fractures, while unsatisfactory in 8.7%. The mean visual analog scale score of pain decreased from 7.3 ± 05 preoperatively to 1.2 ± 0.7 at the final follow-up, p <.001. Postoperatively, there was significant improvement of Böhler's angle, angle of Gissane, calcaneal width, and height, p < .001. Factors associated with better functional outcomes included reduced time lapse to surgery, p = .032, and more accurate restoration of the calcaneal parameters. Management of intra-articular calcaneal fractures by minimally invasive osteosynthesis using cannulated screws can achieve satisfactory functional and radiological outcomes. Better outcomes are associated with reduced time lapse to surgery, and accurate reduction and restoration of calcaneal angles, height, and width.

Biofilm and its implications postfracture fixation: All I need to know

Biofilm represents an organized multicellular community of bacteria having a complex 3D structure, formed by bacterial cells and their self-produced extracellular matrix. It usually attaches to any foreign body or fixation implant. It acts as a physical protective barrier of the bacteria from the penetration of antibodies, bacteriophages, granulocytes and biocides, antiseptics, and antibiotics. Biofilm-related infections will increase in the near future. This group of surgical site infections is the most difficult to diagnose, to suppress, to eradicate, and in general to manage. Multispecialty teams involved in all stages of care are an effective way to improve results and save resources and time for the benefit of patients and the health system. Significant steps have occurred recently in the prevention and development of clever tools that we can employ in this everlasting fight with the bacteria. Herein, we attempt to describe the nature and role of the "biofilm" to the specific clinical setting of surgical site infections in the field of orthopaedic trauma surgery.

Zinc alloy-based bone internal fixation screw with antibacterial and anti-osteolytic properties

There is no targeted effective treatment for patients undergoing internal fixation surgery/two-stage total joint revision surgery with a high risk of postoperative infection and osteolysis, while the rate of reoperation due to infection and osteolysis remains high. In this study, we report a pioneering application of implants made of biodegradable Zn–Ag alloy with active antibacterial and anti-osteolytic properties in three classical animal models, illustrating antibacterial, anti-osteolysis, and internal fixation for fractures. The antibacterial activity of the Zn–2Ag alloy was verified in a rat femur osteomyelitis prevention model, while the anti-osteolytic properties were evaluated using a mouse cranial osteolysis model. Moreover, the Zn–2Ag based screws showed similar performance in bone fracture fixation compared to the Ti–6Al–4V counterpart. The fracture healed completely after 3 months in the rabbit femoral condyle fracture model. Furthermore, the underlying antibacterial mechanism may include inhibition of biofilm formation, autolysis-related pathways, and antibiotic resistance pathways. Osseointegration mechanisms may include inhibition of osteoclast-associated protein expression, no effect on osteogenic protein expression, and no activation of related inflammatory protein expression. The empirical findings here reveal the great potential of Zn–Ag-based alloys for degradable biomaterials in internal fixation surgery/two-stage total joint revision surgery for patients with a high risk of postoperative infection and osteolysis.

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Zn–2Ag alloy is designed for orthopedic applications.

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Zn–2Ag alloy exhibit outstanding antibacterial properties in a rat femur osteomyelitis prevention model.

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Zn–2Ag alloy exhibit outstanding anti-osteolytic properties in a mouse cranial osteolysis model.

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Zn-2Ag based screws showed reliable performance in bone fracture fixation in the rabbit femoral condyle fracture model.

A Machine Learning Algorithm to Identify Patients with Tibial Shaft Fractures at Risk for Infection After Operative Treatment

BACKGROUND

Risk stratification of individual patients who are prone to infection would allow surgeons to monitor high-risk patients more closely and intervene early when needed. This could reduce infection-related consequences such as increased health-care costs. The purpose of this study was to develop a machine learning (ML)-derived risk-stratification tool using the SPRINT (Study to Prospectively Evaluate Reamed Intramedullary Nails in Patients with Tibial Fractures) and FLOW (Fluid Lavage of Open Wounds) trial databases to estimate the probability of infection in patients with operatively treated tibial shaft fractures (TSFs).

METHODS

Patients with unilateral TSFs from the SPRINT and FLOW trials were randomly split into derivation (80%) and validation (20%) cohorts. Random forest algorithms were used to select features that are relevant to predicting infection. These features were included for algorithm training. Five ML algorithms were trained in recognizing patterns associated with infection. The performance of each ML algorithm was evaluated and compared based on (1) the area under the ROC (receiver operating characteristic) curve (AUC), (2) the calibration slope and the intercept, and (3) the Brier score.

RESULTS

There were 1,822 patients included in this study: 170 patients (9%) developed an infection that required treatment, 62 patients (3%) received nonoperative treatment with oral or intravenous antibiotics, and 108 patients (6%) underwent subsequent surgery in addition to antibiotic therapy. Random forest algorithms identified 7 variables that were relevant for predicting infection: (1) Gustilo-Anderson or Tscherne classification, (2) bone loss, (3) mechanism of injury, (4) multitrauma, (5) AO/OTA fracture classification, (6) age, and (7) fracture location. Training of the penalized logistic regression algorithm resulted in the best-performing prediction model, with AUC, calibration slope, calibration intercept, and Brier scores of 0.75, 0.94, 0.00, and 0.076, respectively, in the derivation cohort and 0.81, 1.07, 0.09, and 0.079, respectively, in the validation cohort.

CONCLUSIONS

We developed an ML prediction model that can estimate the probability of infection for individual patients with TSFs based on patient and fracture characteristics that are readily available at hospital admission.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of Sinus Tarsal Approach Compared With Conventional L-Shaped Lateral Approach in the Treatment of Calcaneal Fractures: A Meta-Analysis

Background: This study aims to compare the efficacy of the sinus tarsal approach (STA) with that of the conventional L-shaped lateral approach (CLSLA) in the treatment of calcaneal fractures by meta-analysis.

Methods: PubMed, Embase, Web of Science, the Chinese National Knowledge Infrastructure, and China Wanfang database were searched to collect clinical randomized or non-randomized controlled trials of STA and CLSLA in the treatment of calcaneal fractures from January 2010 to May 2020. The data were analyzed by Stata 15.0 software.

Results: A total of 12 clinical trials were included, all of which were retrospective studies, including 961 patients. The results showed that when STA was compared with CLSLA, there was no difference in operation time with mean difference (MD) = −5.51 [95% confidence interval (CI): −12.57 to 1.55, P > 0.05], less bleeding during operation with MD = −18.49 (95% CI:−23.79 to −13.18), no difference in Böhler angle after an operation with MD = 0.78 (95% CI: −0.09 to 1.65) and in Gissane angle with MD = −0.07 (95% CI: −1.90 to 1.77), no difference in American Orthopedic Foot and Ankle Society score with MD = 2.16 (95% CI: −1.07 to 5.38), higher-excellent and better rate of Maryland food function with relative ratio = 1.12 (95% CI: 1.04 to 1.20), and lower of incidence of postoperative complications with relative ratio = 0.23 (95% CI: 0.14–0.37).

Conclusion: STA was more effective than CLSLA in the treatment of calcaneal fractures. Moreover, STA had advantages in less intraoperative bleeding, higher-excellent and better rate of Maryland foot function, lower incidence of postoperative complications, and higher safety.

Nomogram prediction of surgical site infection of HIV-infected patients following orthopedic surgery: a retrospective study

BACKGROUND

Surgical site infection (SSI) is a devastating complication of orthopedic surgery, related with increased morbidity and mortality. This study was performed with the aim to compare the SSI rate in human immunodeficiency virus HIV-positive patients, to identify other risk factors for SSI and to establish a nomogram model to predict the risk of SSI.

METHODS

A total of 101 HIV-positive individuals following orthopedic surgery patients admitted to Beijing Ditan Hospital. Their characteristics were gathered. The univariate and multiple logistic regression analysis were performed to explore the risk factors of SSI. And the Nomogram prediction model was constructed and verified.

RESULTS

The independent predictive factors of SSI included CD4 (Odds ratio [OR], 0.041; P = 0.040), erythrocyte sedimentation rate (ESR) (OR, 89.773; P = 0.030), and procalcitonin (PCT) (OR, 220.746; P = 0.006). The scoring nomogram model was as follows: Logit (SSI) = - 2.63589-0.00314*CD4 < 430.75 = 1) + 0.04695*(ESR < 17.46 = 1) + 2.93694*(PCT < 0.22 = 1). The area under the Receiver Operating Characteristic (ROC) curve was 0.946. The cutoff score was - 2.1026 with a sensitivity of 93.33% and a specificity of 84.88%.

CONCLUSIONS

CD4, ESR, PCT might affect the occurrence of SSI after orthopedic surgery. The nomogram model constructed in this study is helpful for predicting the probability of SSI.

Biodegradable Zn-Cu alloys show antibacterial activity against MRSA bone infection by inhibiting pathogen adhesion and biofilm formation

Bone and joint-related infections remain the primary and most critical complications of orthopedic surgery. We have innovatively prepared Zn-Cu alloys to achieve outstanding material and antibacterial properties. In this study, we systematically assessed the material properties and antibacterial activity of these Zn-Cu alloys. Our results showed that the Zn-2Cu alloy had the best mechanical properties, biocompatibility, and osteogenic properties. Findings of microbial cultures, CLSM, SEM, and TEM indicated that Zn-2Cu alloy can inhibit both coagulase-positive and coagulase-negative staphylococci, as well as antibiotic-resistant strains (MRSA and MRSE), by preventing the bacteria adhesion and the biofilm formation. Zn-2Cu alloy could broadly affect the expression of MRSA genes associated with adhesion, autolysis, biofilm formation, virulence, and drug resistance. A rat femur intramedullary nail infection-prevention model was established and the Zn-2Cu alloy-treated group showed significant antibacterial activity against MRSA and reduced the inflammatory toxic side-effects and infection-related bone loss. Collectively, our results indicate the potential utility of Zn-Cu alloy implants with 2 wt% Cu in treating orthopedic infections. Statement of significance: Osteomyelitis is a serious complication of orthopedic surgeries. Wide use of antibiotics contributes to the appearance of multi-drug resistant strains like methicillin-resistant staphylococcus aureus (MRSA). Alternatively, anti-osteomyelitis implants with broad-spectrum antibacterial properties can be favorable. Here, the antibacterial performance of biodegradable Zn-Cu alloys was evaluated with four different bacteria strains including antibiotic-resistant strains (MRSA and MRSE). Zn-Cu alloys exert excellent bacterial killing capability in all strains. In a rat femur infection model, the alloy showed significant antibacterial activity against MRSA and reduced inflammatory toxic side-effects as well as infection-related bone loss. The antibacterial property of Zn-2Cu alloy was associated with inhibition of gene expression related to wall synthesis, adhesion, colonization, biofilm formation, autolysis, and secretion of virulence factors in MRSA.

Extended Antibiotic Coverage in the Management of Type II Open Fractures

Background: Responsible antibiotic stewardship requires surgeons treating open fractures to use the narrowest appropriate antibiotic coverage possible to prevent infection. Because inter-observer agreement about the application of the Gustilo-Anderson open fracture classification is moderate at best, antibiotic selection can be overly aggressive. The purpose of this study was to evaluate the outcomes of Type II open fractures treated with gram-positive coverage only (GP) versus broad-spectrum antibiotic coverage (BS) with piperacillin-tazobactam (PT). Methods: A retrospective review of all Type II open fractures was performed at a single Level one trauma center over a 5-year period (2013-2017). All patients received prophylactic antibiotics on arrival on the basis of the best judgment of classification by the house officer on call. The final Gustilo-Anderson open fracture classification was assigned intra-operatively by the operating surgeon. Two groups were created, a GP antibiotic group (cefazolin and/or clindamycin) and a BS group (PT). A minimum of 3-month follow-up was required for inclusion. Patient demographics, cost of treatment, fracture-related infection (FRI) rates, and infecting bacteria were assessed. Results: The GP group contained 70 open fractures and the BS group contained 74 open fractures. Between the groups, there were no differences in age, sex, race, Body Mass Index, American Society of Anesthesiologists Class, or smoking status. There were no statistical differences in Injury Severity Score (ISS), fracture location, fixation method, or rates of staged management with external fixation. There was no difference in FRI rate between the GP and BS groups (8.6% versus 10.8%; p = 0.78). The bacteria responsible for FRI were similar in the GP and BS groups. The hospital charge for PT was 4.39 × the cost of cefazolin. Conclusions: The use of BS coverage in Type II open fractures does not result in a lower infection rate and adds significant cost to patient care. These data support the use of a GP-only antibiotic regimen for Type II open fractures.

Risk factors for surgical site infections with the Sinus Tarsi Approach in displaced intra-articular calcaneal fractures; a prospective cohort study with a minimum of one year follow-up

BACKGROUND

In the last decade, the sinus tarsi approach (STA) has gained interest over the extensile lateral approach (ELA) in the operative treatment of displaced intra-articular calcaneal fractures (DIACF's), mainly because of the lower rate of surgical site infections (SSIs). However, most studies are small and retrospective. The aim of this study was to evaluate the rate of SSIs of the STA in a large, prospective series of patients and to identify predictors for SSIs.

METHODS

In this prospective cohort study, all consecutive patients who were operatively treated for a DIACF in our Level 1 trauma center between August 2012 and January 2019 were included and followed for at least one year. All operative procedures were performed by two specialized foot and ankle trauma surgeons using the STA. Using multinomial logistic regression, risk factors for SSIs were identified.

RESULTS

A total of 237 calcaneal fractures in 214 patients were included, of which 179 underwent open reduction and internal fixation and 58 a primary arthrodesis. Most patients were male (73.6%) and the mean age was 45.9 years. There were 16 patients that developed a SSI (6.8%), of which 9 (3.8%) were deep and 7 (3%) were superficial infections. The multivariate analysis pointed out that surgery within one week after injury increased the chance of a SSI, as well as an ASA of 2 or higher and more than 150 cc of blood loss during the procedure.

CONCLUSION

This study confirms the low risk of SSI in DIACFs treated via STA. Significant predictors for SSIs were surgery within one week after injury, ASA of 2 or higher and blood loss > 150cc.

Assessing structural and functional response of murine vasculature to acute β-adrenergic stimulation in vivo during hypothermic and hyperthermic conditions

Background: Because of the importance of adrenoreceptors in regulating the cardiovascular (CV) system and the role of the CV system in thermoregulation, understanding the response to these two stressors is of interest. The purpose of this study was to assess changes of arterial geometry and function in vivo during thermal and β-adrenergic stress induced in mice and quantified by MRI.Methods: Male mice were anesthetized and imaged at 7 T. Anatomical and functional data were acquired from the neck (carotid artery), torso (suprarenal and infrarenal aorta and iliac artery) and periphery (femoral artery). Intravenous dobutamine (tail vein catheter, 40 µg/kg/min, 0.12 mL/h) was used as β-adrenergic stressor. Baseline and dobutamine data were acquired at minimally hypothermic (35 °C) and minimally hyperthermic (38 °C) core temperatures. Cross-sectional vessel area and maximum cyclic strain were measured across the cardiac cycle.Results: Vascular response varied by location and by core temperature. For minimally hypothermic conditions (35 °C), average, maximum and minimum areas decreased with dobutamine only at the suprarenal aorta (avg: -17.9%, max: -13.5%, min: -21.4%). For minimally hyperthermic conditions (38 °C), vessel areas decreased between baseline and dobutamine at the carotid (avg: -19.6%, max: -15.5%, min: -19.3%) and suprarenal aorta (avg: -24.2%, max: -17.4%, min: -17.3%); whereas, only the minimum vessel area decreased for the iliac artery (min: -14.4%). Maximum cyclic strain increased between baseline and dobutamine at the iliac artery for both conditions and at the suprarenal aorta at hyperthermic conditions.Conclusions: At hypothermic conditions, the vessel area response to dobutamine is diminished compared to hyperthermic conditions where the vessel area response mimics normothermic dobutamine conditions. The varied response emphasizes the need to monitor and control body temperature during medical conditions or treatments that may be accompanied by hypothermia, especially when vasoactive agents are used.