Risk factors and complications contributing to mortality in elderly patients with fall-induced femoral fracture: A cross-sectional analysis based on trauma registry data of 2,407 patients

Systematic analysis of the occurrence characteristics and impact on hospitalization costs of trauma complications

BACKGROUND

Trauma complications increase the burden of disease and hospitalization costs for patients. More research evidence is needed on how to more effectively prevent these complications and reduce hospitalization costs based on the characteristics of trauma patients. Therefore, this study will systematically analyze the characteristics of trauma complications and their specific impact on hospitalization costs.

METHODS

This is a multi-center retrospective study of trauma hospitalizations from 2018 to 2023. Associations between population characteristics, trauma features, and each complication occurrence were investigated using multiple correspondence analysis. Logistic regression analysis assessed factors influencing trauma complications. Additionally, a generalized linear model analyzed the relative increase in hospital costs for each complication.

RESULTS

A total of 48,032 trauma patients were included, with 22.0% experiencing at least one complication. Thrombosis is more prevalent among elderly women (aged ≥65) with pelvic and extremity trauma. In men aged 18-44 years, respiratory insufficiency and post-traumatic anemia primarily occurred in cases of head injuries and multiple injuries. Chest and multiple injuries predispose people aged 45-64 to pneumonia and electrolyte disorders. Body surface injuries are prone to surgical site infections. Complications resulted in an average relative increase in overall hospitalization costs of 1.32-fold, with thrombosis (1.58-fold), respiratory insufficiency (1.11-fold), post-traumatic anemia (0.58-fold), surgical site infection (0.48-fold), pneumonia (0.53-fold), electrolyte disorders (0.47-fold).

CONCLUSIONS

This study systematically analyzed the occurrence characteristics of trauma complications and the burden trends of hospitalization costs due to complications, providing a reference for the formulation of trauma classification and management strategies.

Role of the Stress Index in Predicting Mortality among Patients with Traumatic Femoral Fractures

BACKGROUND

Traumatic femoral fractures, often resulting from high-energy impacts such as traffic accidents, necessitate immediate management to avoid severe complications. The Stress Index (SI), defined as the glucose-to-potassium ratio, serves as a predictor of mortality and adverse outcomes in various trauma contexts. This study aims to evaluate the prognostic value of the SI in patients with traumatic femoral fractures.

METHODS

This retrospective cohort study included adult trauma patients aged 20 or above with traumatic femoral fractures from the Trauma Registry System at a level 1 trauma center in southern Taiwan between 1 January 2009 and 31 December 2022. At the emergency room, serum electrolyte levels were assessed using baseline laboratory testing. By dividing blood glucose (mg/dL) by potassium (mEq/L), the SI was calculated. The best cut-off value of the SI for predicting mortality was determined using the Area Under the Curve (AUC) of Receiver Operating Characteristic (ROC).

RESULTS

A total of 3717 patients made up the final group, of which 3653 survived and 64 died. In comparison to survivors, deceased patients had substantially higher blood glucose levels (199.3 vs. 159.0 mg/dL, p < 0.001) and SIs (53.1 vs. 41.6, p < 0.001). The optimal SI cut-off value for predicting mortality was 49.7, with a sensitivity of 53.1% and a specificity of 78.7% (AUC = 0.609). High SI was associated with increased mortality (4.2% vs. 1.0%, p < 0.001) and longer hospital stays (12.8 vs. 9.5 days, p < 0.001). The adjusted odds ratios of mortality, controlled by comorbidities, the Glasgow Coma Scale, and the Injury Severity Score, were significantly higher in patients with a higher SI (AOR 2.05, p = 0.016) than those with a lower SI.

CONCLUSIONS

Elevated SI upon admission correlates with higher mortality and extended hospital stay in patients with traumatic femoral fractures. Although the SI has a moderate predictive value, it remains a useful early risk assessment tool, necessitating further prospective, multi-center studies for validation and standardization.

Transforaminal Full-Endoscopic Ventral Facetectomy: Midterm Results and Factors Associated with Poor Surgical Outcomes

BACKGROUND

 Full-endoscopic spine surgery (FESS) is a well-established procedure for herniated nucleus pulposus. It is a minimally invasive surgery that can be performed under local anesthesia through only an 8-mm skin incision. With improvements in surgical equipment such as high-speed drills, the indications for FESS have expanded to include lumbar spinal stenosis (LSS). We perform a transforaminal full-endoscopic ventral facetectomy (TF-FEVF) for unilateral nerve root-type lateral recess stenosis (LRS) using a transforaminal approach under local anesthesia.The aim of this study was to examine the postoperative results of TF-FEVF for LRS and to identify factors associated with poor surgical outcomes. 85 patients who underwent TF-FEVF for LRS under local anesthesia. Clinical outcomes were determined by visual analog scale (VAS) and the modified MacNab criteria. Evaluation was performed using magnetic resonance imaging (MRI), computed tomography (CT), and flexion-extension radiographs.

METHODS

 This study involved 85 patients (47 males and 38 females) who underwent TF-FEVF for LRS. The mean age was 70.5 years and the mean follow-up duration was 14.8 months. Data were collected on sex, age, level of operation, diagnosis, history of spine surgery at the same level, and duration of follow-up. The diagnosis was categorized as LSS with or without disk bulging. Clinical evaluation was performed using the VAS and modified MacNab criteria. MRI was used to evaluate the degree of disk degeneration, vertebral endplate degeneration, disk height, thickening of the ligamentum flavum, and stenosis. Bony stenosis was evaluated using CT. Sagittal translation and sagittal angulation were also measured by flexion-extension radiographs, and the Cobb angle was measured using a standing front view radiograph. All variables were compared between patients with excellent/good outcomes (E/G group) and those with fair/poor outcomes (F/P group) using the modified MacNab criteria.

RESULTS

 Postoperative VAS showed that leg pain decreased from 59.0 ± 28.6 preoperatively to 17.9 ± 27.2 at the final follow-up (p < 0.01) and that lower back pain also decreased from 60.7 ± 26.6 preoperatively to 27.3 ± 28.6 at final follow-up (p < 0.01). According to the modified MacNab criteria, the results during the final follow-up were excellent in 39 cases, good in 21 cases, fair in 13 cases, and poor in 12 cases. There were no significant differences in sex, age, diagnosis, history of spine surgery, and duration of follow-up periods between the 60 cases (70.6%) in the E/G group and the 25 cases (29.4%) in the F/P group. Imaging evaluation revealed statistically significant differences between the E/G group and the F/P group in intervertebral angle flexion (3.2 vs. 0.4 degrees; p < 0.05), sagittal angulation (4.3 vs. 8.1 degrees; p < 0.05), slip in flexion (0.9 vs. 2.8 mm; p < 0.05), sagittal translation (0.7 vs. 1.6 mm; p < 0.05), and Cobb angle (-0.5 vs. -1.9 degrees; p < 0.05).

CONCLUSION

 Midterm results of TF-FEVF were generally favorable; factors contributing to good or poor TF-FEVF outcomes were large sagittal angulation, large sagittal translation, and concave side.

Full-endoscopic spine surgery in oldest old patients aged over 90 years:A case report

BACKGROUND

Transforaminal full-endoscopic spine surgery (FESS) is the least invasive spinal surgery and can be performed under local anesthesia. In Japan, the population is rapidly aging and the number of spinal surgeries performed in the elderly is also increasing.

OBJECT

In this report, we describe 3 patients aged 90 years or older in whom we performed FESS under local anesthesia.

CASE

The first case was a 90-year-old man who presented with severe leg pain. He had multiple medical comorbidities and was unsuitable for general anesthesia. We performed FESS. After surgery, the leg pain resolved with full recovery of muscle strength. He was discharged with no perioperative complications. The second case was a 90-year-old man who presented with severe leg pain. MRI showed a herniated nucleus pulposus and foraminal stenosis at L4/5. We performed FESS. The leg pain improved immediately after surgery. The third case was a 91-year-old woman in whom we diagnosed left L5 radiculopathy due to foraminal stenosis at L5/S1. After surgery, her leg pain was relieved.

CONCLUSION

FESS is a good surgical procedure for elderly patients who are in a poor general condition because it is minimally invasive and can be performed under local anesthesia with early mobilization. J. Med. Invest. 71 : 169-173, February, 2024.

Prevalence and associations of sarcopenia, obesity and sarcopenic obesity in end-stage knee osteoarthritis patients

OBJECTIVE

To identify the prevalence of obesity, sarcopenia, sarcopenic obesity in end-stage knee osteoarthritis (KOA) patients and analyze influences of obesity and sarcopenia in the progression of KOA.

METHODS

A cross-sectional study was carried out among end-stage KOA patients who consecutively admitted to Orthopedic Department for TKA. We suppose that the level of decreased physical activities would be influenced by unilateral or bilateral KOA. Patient information, albumin, hemoglobin, pace, step frequency, number of comorbid conditions were collected. Bioelectrical impedance analyzer was used to analyze body composition. Obesity, sarcopenia, sarcopenic obesity rate were analyzed with accepted diagnosis criteria. Correlations between body mass index (BMI) or age and fat mass (FM), appendicular skeletal muscle mass (ASM) were analyzed.

RESULTS

138 patients (male 30, female 108) in southwest of China including 67 patients with unilateral KOA and 71 patients with bilateral KOA were analyzed. No statistic difference was found in mean albumin, prealbumin and hematocrystallin, body composition values and number of comorbid conditions. We found that BMI was positively correlated with FM (Male: R2 = 0.7177, p < 0.0001, Female: R2 = 0.8898, p < 0.0001), ASM (Male: R2 = 0.2640, p = 0.0037, Female: R2 = 0.2102, p < 0.0001), FM index (FMI) (Male: R2 = 0.6778, p < 0.0001, Female: R2 = 0.8801, p < 0.0001), and ASM index (ASMI) (Male: R2 = 0.3600, p = 0.0005, Female: R2 = 0.4208, p < 0.0001) in end-stage KOA patients. However, age was not obviously correlated with FM or FMI (Male: FM, R2 = 0.006911, p = 0.3924; FMI, R2 = 0.7554, p = 0.0009196; Female: FM, R2 = 0.001548, p = 0.8412; FMI, R2 = 0.002776, p = 0.7822). And slightly negatively correlated with ASM (Male: R2 = 0.05613, p = 0.0136, Female: R2 = 0.01327, p = 0.5433) and ASMI (Male: R2 = 0.02982, p = 0.3615; Female: R2 = 0.03696, p = 0.0462). The prevalence of obesity, sarcopenia and obesity sarcopenia differs according to different diagnosis criteria. No difference in the occurrence rate of obesity was found between bilateral KOA and unilateral KOA patients, and occurrence rates of sarcopenia and sarcopenic obesity were statistically higher in bilateral KOA than that in unilateral KOA patients.

CONCLUSIONS

Obesity, sarcopenia and sarcopenic obesity are highly prevalent in end-stage KOA patients, sarcopenic obesity are more prevalent in bilateral KOA patients than that in unilateral KOA patients.

Analysis of Trauma Characteristics Between the Older and Younger Adult Patient from the Pan Asian Trauma Outcome Study Registry (PATOS)

OBJECTIVE

Asia is experiencing a demographic shift toward an aging population at an unrivaled rate. This can influence the characteristics and outcomes of trauma. We aim to examine different characteristics of older adult trauma patients compared to younger adult trauma patients and describe factors that affect the outcomes in Asian countries.

METHODS

This is a retrospective, international, multicenter study of trauma across participating centers in the Pan Asian Trauma Outcome Study (PATOS) registry, which included trauma cases aged ≥18 years, brought to the emergency department (ED) by emergency medical services (EMS) from October 2015 to November 2018. Data of older adults (≥65 years) and younger adults (<65 years) were analyzed and compared. The primary outcome measure was in-hospital mortality, and secondary outcomes were disability at discharge and hospital and intensive care unit (ICU) length of stays.

RESULTS

Of 39,804 trauma patients, 10,770 (27.1%) were older adults. Trauma occurred more among older adult women (54.7% vs 33.2%, p < 0.001). Falls were more frequent in older adults (66.3% vs 24.9%, p < 0.001) who also had higher mean Injury Severity Score (ISS) compared to the younger adult trauma patient (5.4 ± 6.78 vs 4.76 ± 8.60, p < 0.001). Older adult trauma patients had a greater incidence of poor Glasgow Outcome Scale (GOS) (13.4% vs 4.1%, p < 0.001), higher hospital mortality (1.5% vs 0.9%, p < 0.001) and longer median hospital length of stay (12.8 vs 9.8, p < 0.001). Multiple logistic regression revealed age (adjusted odds ratio [AOR] 1.06, 95%CI 1.02-1.04, p < 0.001), male sex (AOR 1.60, 95%CI 1.04-2.46, p = 0.032), head and face injuries (AOR 3.25, 95%CI 2.06-5.11, p < 0.001), abdominal and pelvic injuries (AOR 2.78, 95%CI 1.48-5.23, p = 0.002), cardiovascular (AOR 2.71, 95%CI 1.40-5.22, p = 0.003), pulmonary (AOR 3.13, 95%CI 1.30-7.53, p = 0.011) and cancer (AOR 2.03, 95%CI 1.02-4.06, p = 0.045) comorbidities, severe ISS (AOR 2.06, 95%CI 1.23-3.45, p = 0.006), and Glasgow Coma Scale (GCS) ≤8 (AOR 12.50, 95%CI 6.95-22.48, p < 0.001) were significant predictors of hospital mortality.

CONCLUSIONS

Older trauma patients in the Asian region have a higher mortality rate than their younger counterparts, with many significant predictors. These findings illustrate the different characteristics of older trauma patients and their potential to influence the outcome. Preventive measures for elderly trauma should be targeted based on these factors.

Biomechanical properties and clinical significance of cancellous bone in proximal femur: A review

Trabecular bone plays an important role in the load-bearing capacity of the femur. Understanding the structural characteristics, biomechanics, and mechanical conduction of the trabecular bone is of great value in studying the mechanism of fractures and formulating surgical plans. The past decade has witnessed unprecedented progress in imaging, biomechanics and finite element analysis techniques, translating into a better understanding of trabecular bone. This article reviews the research progress achieved over the years regarding femoral trabecular bone, especially on factors influencing the strength of the proximal femoral cancellous bone and cancellous bone microfractures and provides a comprehensive overview of the latest findings on proximal femoral trabecular bone and their clinical significance.

Trauma-related acute kidney injury during inpatient care of femoral fractures increases the risk of mortality: A claims data analysis

Objectives: Although femoral fractures can hit anyone, they carry an especially high burden in the elderly and are multifaceted in their injury pattern, related complications, and subsequent therapeutic strategies. An often underestimated posttraumatic risk is the development of trauma-related acute kidney injury (TRAKI). However, for TRAKI, no outcome study with a large data approach exists addressing fractures. Therefore, we analyzed the development of TRAKI in regard to different covariates and quantified the association of TRAKI with overall mortality. Design: Retrospective cohort study with claims data. Setting and participants: 119,000 patients from Germany with femur fracture. Methods: We calculated cumulative mortality, mortality rates per 100 person-years (both occurring within 180 days after fracture), and adjusted hazard ratios with 95%-confidence intervals (CI). Results: Patients with femur shaft fractures showed an incidence of 6.1% for TRAKI, followed by patients with femur neck fractures with an incidence of 5.7%, and by patients with distal fractures with an incidence of 4.5%, respectively. Overall, in patients with any femur fracture, we found a 3.17-times higher mortality rate (95%-CI: 3.02-3.26) during 180 days of observation in patients who developed TRAKI in comparison to patients without. The risk for development of TRAKI was significantly increased with increasing TRAKI stage, age, and time until surgical intervention. Conclusions and implications: In conclusion, patients suffering from proximal-, shaft-, and distal femoral fracture face an over 3-times higher 180 day-mortality rate in case of posttraumatic TRAKI, which should be considered in peri-traumatic care to improve the long-term outcome of these patients.

Which hospital-acquired conditions matter the most in trauma? An evidence-based approach for prioritizing trauma program improvement

BACKGROUND

Prevention of hospital-acquired conditions (HACs) is a focus of trauma center quality improvement. The relative contributions of various HACs to postinjury hospital outcomes are unclear. We sought to quantify and compare the impacts of six HACs on early clinical outcomes and resource utilization in hospitalized trauma patients.

METHODS

Adult patients from the 2013 to 2016 American College of Surgeons Trauma Quality Improvement Program Participant Use Data Files who required 5 days or longer of hospitalization and had an Injury Severity Score of 9 or greater were included. Multiple imputation with chained equations was used for observations with missing data. The frequencies of six HACs and five adverse outcomes were determined. Multivariable Poisson regression with log link and robust error variance was used to produce relative risk estimates, adjusting for patient-, hospital-, and injury-related factors. Risk-adjusted population attributable fractions estimates were derived for each HAC-outcome pair, with the adjusted population attributable fraction estimate for a given HAC-outcome pair representing the estimated percentage decrease in adverse outcome that would be expected if exposure to the HAC had been prevented.

RESULTS

A total of 529,856 patients requiring 5 days or longer of hospitalization were included. The incidences of HACs were as follows: pneumonia, 5.2%; urinary tract infection, 3.4%; venous thromboembolism, 3.3%; surgical site infection, 1.3%; pressure ulcer, 1.3%; and central line-associated blood stream infection, 0.2%. Pneumonia demonstrated the strongest association with in-hospital outcomes and resource utilization. Prevention of pneumonia in our cohort would have resulted in estimated reductions of the following: 22.1% for end organ dysfunction, 7.8% for mortality, 8.7% for prolonged hospitalization, 7.1% for prolonged intensive care unit stay, and 6.8% for need for mechanical ventilation. The impact of other HACs was comparatively small.

CONCLUSION

We describe a method for comparing the contributions of HACs to outcomes of hospitalized trauma patients. Our findings suggest that trauma program improvement efforts should prioritize pneumonia prevention.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Effect of Age on the Patterns of Traumatic Femoral Fractures: Seven Years of Experience at a Regional Tertiary Hospital

Objective

Femoral fractures are a common cause of mortality and functional loss, mainly among older people, and there are few studies about the age in relation to traumatic femoral fractures. The aim of this study was to investigate the effect of age on the patterns of traumatic femoral fractures in patients presenting to our regional tertiary hospital.

Methods

The records of 2020 patients who presented with traumatic femoral fractures between 2013 and 2019 were retrospectively reviewed. The patients' clinical and radiographic records were reviewed. Univariate and multivariable logistic regression were used to identify independent risk factors for associated injuries and complications.

Results

The patients were divided into a child group (CH group, n = 342) aged under 18 years, a young adult group (YA group, n = 484) aged 18–60 years, and an older people group (OP group, n = 1194) aged 60 years and over. There were significant differences among the three groups in several indexes, such as sex ratio (χ² = 301.699, p < 0.001), osteoporosis (χ² = 375.463, p < 0.001), injury time of day (χ² = 114.913, p < 0.001), injury cause (χ² = 748.187, p < 0.001), injury location (χ² = 490.153, p < 0.001), fracture side (χ² = 57.000, p < 0.001), fracture site (χ² = 806.650, p < 0.001), associated injuries (χ² = 322.921, p < 0.001), coma after injury (χ² = 147.814, p < 0.001), non‐surgery‐related complications (χ² = 7.895, p = 0.019), and surgery‐related complications (χ² = 82.186, p < 0.001). The YA group had a significantly higher percentage of patients with surgery‐related complications than the OP group. The OP group had a higher frequency of non‐surgery‐related complications than the YA group and CH group. The most common non‐surgery‐related complications were pneumonia (7.1%) in the OP group and deep venous thrombosis (6.4%) in the YA group. Multivariable logistic regression showed that young adults, high‐energy injury, outdoors, coma after injury, and fracture sites except for the proximal region were independent risk factors for associated injuries. Older age, male, and fracture site except for the proximal region were independent risk factors for complications.

Conclusions

Traumatic femoral fractures are mostly the result of low‐energy trauma and predominantly affect the proximal site of the femur among older people. A higher rate of shaft fractures, fractures occurring outdoors, and associated injuries were observed among young adults and children than among older people.

Partial pressure of oxygen level at admission as a predictor of postoperative pneumonia after hip fracture surgery in a geriatric population: a retrospective cohort study

OBJECTIVE

To identify whether the partial pressure of oxygen in arterial blood (PaO₂) level at admission is an independent risk factor as a prognostic biomarker to predict postoperative pneumonia (POP) in the geriatric population who have undergone hip fracture surgical repair at our hospital.

DESIGN

A retrospective cohort study.

SETTING

This is a retrospective chart review of POP after hip fracture surgery in China.

PARTICIPANTS

In training cohort, patients aged ≥65 years who had hip fracture surgery between 1 January 2018 and 30 November 2019. In the validation cohort, a series of patients who underwent hip fracture surgery between 1 January 2020 and 28 February 2020.

INTERVENTIONS

Receiver operating characteristic (ROC) analysis was used to obtain the area under the ROC curve (AUC) and cut-off values of PaO₂ to predict POP. A binomial logistic regression model was used to identify potential risk factors for POP by analysing demographic distribution factors, laboratory results, preoperative comorbidities and surgical factors. Then the regression model was validated using an independent cohort.

RESULTS

In the training cohort, ROC curves were generated to compare the predictive performance of PaO₂ for the occurrence of POP, and the area under the receiver operating characteristic curve (AUC) was 0.653 (95% CI 0.577 to 0.729, p<0.0001), with sensitivity and specificity values of 60.0% and 63.8%, respectively. The cut-off value of the PaO₂ for POP was 72.5 mm Hg. Binary logistic regression analysis revealed that hypoxaemia (PaO₂ <72.5 mm Hg) at hospital admission (OR=3.000, 95% CI 1.629 to 5.528; p<0.0001) was independent risk factors associated with POP after hip fracture surgery. In the validation cohort, PaO₂ had a predictive effect for POP (AUC 0.71, 95% CI 0.541 to 0.891).

CONCLUSIONS

The current study revealed that the PaO₂ level at hospital admission is a simple and widely available biomarker predictor of POP after hip fracture surgery in elderly patients.

Comparing the accuracy of ICD-based severity estimates to trauma registry-based injury severity estimates for predicting mortality outcomes

INTRODUCTION

Trauma registries have been used internationally for several decades to measure the quality of trauma care between hospitals. Given the significant costs involved in establishing and maintaining trauma registries, and increasing availability of routinely collected, linked health data describing a patient's journey (and inherent cost savings in data re-use), there is significant interest in development of integrated, comprehensive trauma data repositories. However, approaches to estimating injury severity using routinely collected data would need to be developed if routinely collected hospital data were to be used as an alternative/supplement to registries.

OBJECTIVES

This study aimed to compare the accuracy of registry-based injury severity estimates with ICD-based injury severity estimates in predicting mortality outcomes in a cohort of minor and major trauma patients in Queensland, using retrospectively linked trauma registry and hospital admissions data.

METHODS

Queensland Trauma Registry (QTR) data with an admission date between 1 January 2005 and 31 December 2011 was linked with all acute care patients included in the Queensland Hospital Admitted Patient Data Collection (QHAPDC) with a Principal Diagnosis coded with an ICD-10-AM code within Chapter 19 (S00-T98). Abbreviated Injury Scale coding was undertaken manually by QTR trauma data nurses for the registry data. ICD-based injury severity scores (ICISS) were calculated automatically using all injury-related diagnoses captured in the QHAPDC data using the ICISS multiplicative and worst injury method.

RESULTS

There were 92,140 QTR patients admitted between January 2005 and December 2011 with a valid ISS with a matching QHAPDC record (98.4% survived, 1.6% died). ICISS (multiplicative and worst injury approach) showed marginally better predictive accuracy than ISS when predicting mortality across minor and major injury and ICISS showed marginally better predictive accuracy to ISS when restricted to major trauma/high threat to life cases. Both ICISS and ISS restricted to major trauma/high threat to life showed poorer accuracy compared to the predictive performance when both minor and major cases were included.

CONCLUSION

ICD-based predictions were as accurate as ISS-based predictions for this cohort and this study provides evidence to support the potential for using routinely coded hospital data for risk adjustment within State-based trauma data repositories.

A novel surgical concept of transforaminal full-endoscopic lumbar undercutting laminectomy (TE-LUL) for central canal stenosis of the lumbar spine with local anesthesia : A case report and literature review

Full-endoscopic spinal surgery was first developed for the lumbar herniated nucleus pulposus. Mainly, there are two types in the full-endoscopic lumbar surgery : i.e., transforaminal (TF) and interlaminar approach. The surgery can be done under the local anesthesia for the TF approach ; therefore, we need to further develop the TF approach to variety of the spinal disorders. Recently, the TF full-endoscopic surgery has been applied for the spinal canal stenosis. First, transforaminal full-endoscopic lumbar foraminoplasty for the foraminal stenosis ; then, transforaminal lumbar lateral recess decompression for the lateral recess stenosis has been developed. Finally, we have developed the surgical technique to decompress the central stenosis via TF approach under the local anesthesia. Prior to initiate the clinical case, we have attempted the lumbar undercutting laminectomy using a fresh cadaveric spine. After we technically confirmed that the transforaminal full-endoscopic lumbar undercutting laminectomy (TE-LUL) is possible, we applied the technique to the patient whose lung capacity did not allow general anesthesia. The 72 years old female patient with central canal stenosis could be improved her left leg pain and muscle weakness after TE-LUL under the local anesthesia. In this paper, we introduce the surgical technique of the TE-LUL and discuss of the efficacy of the TE-LUL. J. Med. Invest. 66 : 224-229, August, 2019.

Staphylococcus Aureus Osteomyelitis as an Inducer of Tolerance to Escherichia Coli Pyelonephritis: an Experimental Study

The high incidence of osteomyelitis in vulnerable populations like those with multiple injuries or elderly undergoing joint arthroplasties generates the question what may be their responses to subsequent infection by high virulent isolates. Rabbits were subject to two operations at three week intervals; sham osteomyelitis and sham pyelonephritis (group S); sham osteomyelitis and Escherichia coli pyelonephritis (group P); and Staphylococcus aureus osteomyelitis and E. coli pyelonephritis (group OP). Survival was recorded; cytokine stimulation of circulating mononuclear cells (PBMCs) and tissue myeloperoxidase (MPO) activity and bacterial growth were monitored. In some experiments, dalbavancin treatment was given before pyelonephritis. Healthy PBMCs were pre-treated with bone homogenate, S. aureus or both. Mortality of groups S, P and OP after induction of pyelonephritis was 0%, 50% and 8.3% respectively. Tumour necrosis factor-alpha (TNFα) production by PBMCs was significantly lower in the OP group at 48 hours. E. coli bacterial load was similar in groups P and OP at death or sacrifice whereas the MPO activity of group OP was decreased. Production of TNFα was further decreased among dalbavancin treated rabbits; in these rabbits tissue MPO was increased. TNFα production decreased when healthy PBMCs pre-treated with bone homogenate, S. aureus (HKSA) or both were stimulated with E. coli (HKEC); production was further decreased in the presence of anti-TLR4 and anti-TLR9. It is concluded that staphylococcal osteomyelitis modulated the innate immune responses of the host leading to protection from death by highly virulent E. coli. Tolerance to TLR ligands is the most likely mechanism of action.