Prevalence of perilymphatic fistula in patients with sudden-onset sensorineural hearing loss as diagnosed by Cochlin-tomoprotein (CTP) biomarker detection: its association with age, hearing severity, and treatment outcomes.

PURPOSE: To determine the prevalence of perilymphatic fistula (PLF) in sudden-onset sensorineural hearing loss (SSNHL) patients by employing the Cochlin-tomoprotein (CTP) detection test, a specific diagnostic marker for perilymph. We also analyzed the clinical characteristics associated with hearing outcomes in this cohort. METHODS: A total of 74 eligible patients were prospectively enrolled. Following myringotomy, middle ear lavage (MEL) samples underwent the CTP test to identify perilymph leakage. Intratympanic dexamethasone (IT-DEX) therapy was administered, and hearing outcomes were assessed. Control groups comprised patients with chronic otitis media (n = 40) and non-inflammatory middle ears (n = 51) with concurrent MEL sample collection. RESULTS: CTP was positive in 16 (22%) patients. No control samples showed positive results. Multiple regression analysis indicated that age and pre-treatment hearing levels significantly contributed to the CTP value. We found a positive correlation between CTP values, age, and pre-treatment pure-tone averages. Notably, CTP values in SSNHL cases aged 60 and above were significantly higher than in those below 60 years. Patients with positive CTP had significantly worse recovery rates after IT-DEX treatment. CONCLUSION: This study is the first prospective investigation demonstrating a positive relationship between CTP values, age, and hearing severity in SSNHL, indicating that PLF might be the essential cause of SSNHL, particularly in the elderly. Our findings suggest that IT-DEX may be less effective for PLF-associated SSNHL. Future research could reveal that PLF repair surgery is a viable treatment strategy for SSNHL. This study was registered under the UMIN Clinical Trials Registry (UMIN000010837) on 30/May/2013.

Epidemiology of distal radius fracture: a regional population-based study in Japan.

BACKGROUND: Distal radius fracture (DRF) is very common worldwide. In particular, aging countries have numerous patients with DRF, resulting in an urgent need for active preventive measures. As few epidemiological studies have investigated DRF in Japan, we aimed to identify the epidemiological characteristics of patients of all ages with DRF in Japan. METHODS: This descriptive epidemiologic study analyzed data obtained from clinical information of patients diagnosed with DRF from January 1, 2011, to December 31, 2020, at a prefectural hospital in Hokkaido, Japan. We calculated the crude and age-adjusted annual incidences of DRF and described the age-specific incidence, injury characteristics (injury location and cause, seasonal differences, and fracture classification), and 1- and 5-year mortality rates. RESULTS: A total of 258 patients with DRF were identified, of which 190 (73.6%) were female and the mean age (standard deviation) was 67.0 (21.5) years. The crude annual incidence of DRF ranged from 158.0 to 272.6 per 100,000 population/year, and the age-adjusted incidence among female patients demonstrated a significant decreasing trend during 2011-2020 (Poisson regression analysis; p = 0.043). The age-specific incidence differed by sex, with peaks at 10-14 years for males and 75-79 years for females. The most common cause of injury was a simple fall in patients > 15 year of age and sports injuries in patients ≤ 15 years of age. DRFs were most frequently sustained outdoors and were more common in the winter season. In patients > 15 years of age, the proportions of AO/OTA fracture types A, B, and C were 78.7% (184/234), 1.7% (4/234), and 19.6% (46/234), respectively, and 29.1% (68/234) of patients received surgical treatment for DRF. The 1- and 5-year mortality rates were 2.8% and 11.9%, respectively. CONCLUSIONS: Our findings were mostly consistent with previous global studies. Although the crude annual incidence of DRF was relatively high because of recent population aging, the age-adjusted annual incidence among female patients showed a significant decreasing trend during this decade.

AO/OTA 31A3 fractures and postoperative complications in older patients.

BACKGROUND: AO/OTA 31A3 fractures (A3 fractures) have risk for postoperative complications with major impact on morbidity and mortality. For older patients, limited information is available for factors associated with postoperative complications. We aimed to assess factors associated with postoperative complications after surgery using cephalomedullary nails. METHODS: A retrospective cohort study was conducted using the information on patients aged ≥65 years who underwent surgery using cephalomedullary nails for trochanteric fractures due to low-energy trauma in three hospitals. Postoperative complications were diagnosed when patients were identified as nonunion, cutout of lag screw, or nail breakage. First, we compared differences including age, sex, body mass index, American Society of Anesthesiologists physical status classification system, preoperative waking ability, fracture type, nail length, neck shaft angle, reduction method, reduction quality and tip apex distance between patients with and without postoperative complications. Second, multivariable logistic regression analysis was employed to assess factors associated with postoperative complications resulting from A3 fractures. RESULTS: Among 120 patients with A3 fractures, postoperative complications were identified in 12 patients (10.0%). Postoperative complications were significantly more likely to develop among patients with poor reduction quality (adjusted odds ratio [95% confidence interval], 35.0 [4.43-275.9]) and a tip-apex distance ≥25 mm (16.4 [1.92-140.3]). CONCLUSIONS: These findings suggest that surgeons should aim to perform appropriate postoperative reduction and to prevent postoperative complications when using a cephalomedullary nail for A3 fractures among older patients.

Younger age is a significant factor for poorer adherence in fracture patients who received low-intensity pulsed ultrasound: A retrospective study.

BACKGROUND: The factors for poor adherence to therapy in patients with postoperative fracture who are treated with low-intensity pulsed ultrasound remain unknown. Therefore, we designed a retrospective cohort study to determine the various factors for poorer adherence to therapy in patients with postoperative fracture who were treated with low-intensity pulsed ultrasound therapy. METHODS: We retrospectively analyzed the data of postoperative patients who underwent low-intensity pulsed ultrasound after fracture surgery from January 2010 to May 2019. The patients were categorized into two groups as follows: group G, including those with a good adherence rate (>72%), and group P, including those with a poor adherence rate (<72%). Factors, such as age, sex, how the rental cost of low-intensity pulsed ultrasound was paid (by the patients themselves or by the insurance company), living (alone or with someone), insurance claim item (fractures within 3 weeks after osteosynthesis or delayed or non-union fractures), low-intensity pulsed ultrasound device-type (earlier- or next-generation), duration of low-intensity pulsed ultrasound use, fracture site (upper or lower limb), frequency of hospital visits (regular or irregular), and employment status (employed/unemployed) were compared between groups G and P. RESULTS: In total, 96 patients (74 and 22 patients in groups G and P, respectively) who underwent low-intensity pulsed ultrasound were included in the study. Univariate analysis revealed that younger patients (P < 0.001) and patients who did not regularly visit the hospital (P = 0.024) were more likely to have poorer adherence to therapy. Multiple logistic regression analysis revealed that age was the only independent, pertinent factor for poorer adherence to therapy (odds ratio, 8.570; 95% confidence interval, 2.770-26.50; P < 0.001), with a cutoff value of 41 years. CONCLUSIONS: Younger age is a significant factor for poorer adherence in patients undergoing low-intensity pulsed ultrasound therapy.

Combination of radiographic apparent bone gap and nonunion risk determination score improves accuracy of prediction of tibial shaft delayed union.

BACKGROUND: There is a need for a novel therapeutic strategy for an earlier prediction of long bone union failure as compared to previous methodologies. This study aimed to determine whether a combination of two diagnostic tools would result in a more accurate diagnosis of delayed union. METHODS: The inclusion criteria were as follows: patients with tibial shaft fracture who underwent treatment with intramedullary nailing (IMN) as definitive internal fixation (IF). The study included a total of 114 patients with 116 tibial shaft fractures treated with IMN as definitive IF. Radiographic apparent bone gap (RABG) and nonunion risk determination score (NURDS) can be used to predict nonunion. However, this study aimed to determine whether combination of RABG and NURDS could help deduce a more accurate prediction of delayed union. RESULTS: The union rate was found to be 85% (99 fractures), the delayed union rate was found to be 15% (17 fractures), and the rate of nonunion requiring additional surgical intervention was estimated to be 4% (5 out of the 17 delayed union cases). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of RABG were found to be 82.3%, 76.0%, 36.8%, and 96.2%, respectively, when an RABG cutoff value of 5.0 mm was applied to our patient cohort. The sensitivity, specificity, PPV, and NPV of NURDS were found to be 47.1%, 82.0%, 30.8%, and 90.1%, respectively, when a NURDS cutoff value of 8.0% was applied to our patient cohort. When RABG and NURDS were above their respective cutoff values, the sensitivity and PPV were estimated to be 90.0% and 56.3%, respectively. When RABG and NURDS were below their respective cutoff values, the specificity and NPV were estimated to be 90.1% and 98.5%, respectively. CONCLUSIONS: The combination of RABG and NURDS evaluation immediately after surgery helps surgeons identify patients who are at a high risk of delayed union, facilitating careful monitoring of these patients and consideration of additional treatments.

Efficacy of fracture stem in reverse shoulder arthroplasty for 3- or 4-part proximal humerus fractures.

BACKGROUND: This study compared the clinical results of fracture stems and conventional stems using the same glenoid component in reverse shoulder arthroplasty for proximal humerus fractures in the elderly. METHODS: This retrospective study included 35 patients who underwent Grammont-type reverse shoulder arthroplasty for proximal humerus fractures from 2014 to 2020. The average age at surgery was 79.2 (range, 65-92) years, with 33 female shoulders. Fracture types per Neer classification were 3-part fracture, 4-part fracture, in 13 and 22 shoulders, respectively. The final follow-up period was 35 (range, 24-81) months. The Constant score, American Shoulder and Elbow Surgeons score, shoulder range of motion, and healing of greater tuberosities at the final follow-up of AEQUALIS™ REVERSED (Conventional stem group: n = 15) and AEQUALIS™ REVERSED FX (Fractured stem group: n = 20) were retrospectively investigated. RESULTS: There were no statistically significant differences in age at surgery, sex, body mass index, fracture type, waiting time from injury to surgery, or preoperative general condition between the groups. The Constant and American Shoulder and Elbow Surgeons scores of the fractured stem group were significantly higher than those of the conventional stem group (P = 0.038 and P = 0.023, respectively). The anterior elevation and external rotation at the side of the fractured stem group also showed significantly higher values than those of the conventional stem group (fractured stem group vs. conventional stem group: anterior elevation 127° ± 25° vs. 105° ± 35°, P = 0.041; external rotation 28° ± 13° vs. 13° ± 12°, P = 0.015). The greater tuberosity healing rate was 46.7% (7/15) in the conventional stem group and 85.0% (17/20) in the fractured stem group (P＝0.027). CONCLUSIONS: The findings suggest that use of a fracture-specific stem rather than a conventional stem in Grammont-type reverse shoulder arthroplasty for proximal humerus fractures improves tuberosity healing, postoperative range of motion, and clinical scores.

Minimally invasive plate osteosynthesis with locking plate for metastatic humeral fractures.

BACKGROUND: Limited reports have examined the outcomes and complications of minimally invasive plate osteosynthesis (MIPO) with a locking plate (LP) in metastatic humeral fractures. Therefore, this study aimed to evaluate the effectiveness of MIPO in the treatment of metastatic humeral fractures. METHODS: Patients who underwent MIPO for metastatic humeral fractures were included in this study. Data on patient demographics, new Katagiri score, operative time, amount of blood loss, bone union rate, range of motion (ROM) of the shoulder and elbow, and perioperative complications were obtained. RESULTS: Twelve patients (seven men and five women) with 14 fractures were included in this study. The median operative time was 92.6 ± 28.9 min (range, 57-175 min) and the median amount of intraoperative blood loss was 106.1 ± 109.5 g (range, 10-330 g). No patient required surgery-related transfusion. The median duration of acquisition of active elbow ROM of>100° and active shoulder flexion of >90° were 8.9 ± 6.6 days (range, 1-30 days) and 17.5 ± 13.0 days (range, 6-47 days), respectively. The mean follow-up period was 10.0 ± 9.0 months (range, 1-33 months). There were no complications, and no patient required any further surgery for the affected humerus until death. CONCLUSION: MIPO using an LP provided acceptable functional outcomes in advanced-stage cancer patients with metastatic humeral fractures during their limited lifetime.

A comparison between the femoral neck system and other implants for elderly patients with femoral neck fracture: A preliminary report of a newly developed implant.

BACKGROUND: Femoral neck system (FNS) is an implant for patients with femoral neck fracture. It has superior angular and rotatory stability; it is less invasive because of its established locking plate system. To the best of our knowledge, there are no studies yet concerning the clinical outcomes of elderly patients with femoral neck fracture who have been treated using the FNS. METHODS: Data of patients with femoral neck fracture aged >65 years and who had undergone internal fixation with the FNS and other implants were retrospectively analyzed in this study. The follow-up period was a minimum of six months between January 2006 and November 2020. In total, 52 patients were included in the clinical evaluations, using the FNS (group F) was 25 and using other implants (group O) was 27. Outcome measurements were surgical time, the amount of blood loss, union rate and the cases that underwent reoperation. RESULTS: The average surgical time in the group F was 42 ± 13 min (range: 26-83 min) and was shorter than that in the group O (53 ± 21 min, range: 13-111 min, P = 0.032). The average blood loss in the group F was calculated to 36 ± 25 g (range: 0-91 g), while it was 41 ± 40 g (range: 0-169 g) in group O. No significant difference among the groups. The union rate of the group F was 100%, and the reoperation rate of the group F was significantly less than that of the group O (0% vs 22%, P = 0.023). CONCLUSION: Internal fixation using the FNS can be an alternative option with shorter surgical time and lower reoperation rate for elderly patients with femoral neck fracture.

Clinical outcomes of open reduction and internal fixation for intra-articular complex tibial plateau non-union with 3-year minimum follow-up.

BACKGROUND: A tibial plateau fracture is one of the most challenging fractures for both knee and trauma surgeons because of the high incidence of post-traumatic knee osteoarthritis. To our knowledge, there has been no study concerning the clinical outcomes after surgery in patients with non-union of complex intra-articular tibial plateau fractures. Thus, the present study aimed to assess and report the clinical outcomes in them. METHODS: The study included four patients with non-union of complex tibial plateau fractures who underwent failed initial fixation treatment or could not undergo initial fixation owing to concomitant injury and who were followed up with a diagnosis of non-union for a minimum of 6 months. At the latest follow-up, patient-reported outcome measures, including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Oxford 12-item Knee Score (OKS), were assessed. Additionally, the knee range of motion (ROM) was evaluated. RESULTS: The mean duration from the initial surgery to revision surgery was 8.8 months, and the mean duration from the revision surgery to fracture union was 4.8 months. At the latest follow-up, the mean WOMAC score was 9.8 and the mean OKS was 43.5. Additionally, the mean knee ROM values were -11 degrees of extension and 100 degrees of flexion. All four patients had become able to walk without any aid after averaged 4.5-years follow up. CONCLUSION: Favorable clinical outcomes can be achieved following revision surgery involving open reduction and IF in patients with non-union of complex tibial plateau fractures after failed initial treatment. LEVEL OF EVIDENCE: Level IV, Case report.

Predictors of fatal outcome after severe necrotizing fasciitis: Retrospective analysis in a tertiary hospital for 20 years.

BACKGROUND: Prognostic factors for fatal outcomes of patients with necrotizing fasciitis remain unclear. METHODS: We retrospectively analyzed data of patients with necrotizing fasciitis from January 1998 to July 2019 using our hospital's medical database. Clinical characteristics of patients who died during hospitalization or had been discharged were evaluated. Sex, age, body mass index, smoking history, alcohol use, comorbidities (diabetes mellitus, arteriosclerosis obliterans, heart disease, obstructive arteriosclerosis, dialysis, cancer, skin disease, steroid use history), shock vital, physical findings, Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score, sepsis, disseminated intravascular coagulation, fascial administration, tracheal intubation, and surgical treatment (dismemberment and/or debridement) were compared between the survivor (group S) and nonsurvivor (group N) groups. RESULTS: Fifty-five patients with necrotizing fasciitis were included (40 patients in group S and 15 patients in group N). Serum creatine was a significant prognostic factor (odds ratio [OR], 3.03; 95% confidence interval [CI], 0.15-0.75; P = 0.0078), with a cutoff value of 1.56 mg/dL. Moreover, the estimated glomerular filtration rate was a significant prognostic factor (OR, 1.06; 95% CI, 1.02-1.10, P = 0.000548), with a cutoff value of 20.6 mL/min. CONCLUSION: Renal dysfunction is a significant prognostic factor for fatal outcomes of patients with necrotizing fasciitis. LEVEL OF EVIDENCE: Level IV, Case series.

Clinical outcome of conversion from external fixation to definitive internal fixation for open fracture of the lower limb.

INTRODUCTION: Few reports have examined the outcomes and complications of temporary bridging external fixation (EF) in open fracture of the lower limb followed by conversion to open reduction internal fixation (ORIF). The purpose of this study was to evaluate healing rates and complications in patients treated with conversion from external fixation to definitive internal fixation for open fracture of the lower limb. METHOD: Patients who underwent temporary bridging EF and subsequent conversion to internal fixation (IF) for open fracture of the lower limb, with follow-up period ≥12 months were included in this study. Demographic data, Gustilo-Anderson classification, fracture type, duration to definitive surgery, surgical procedure, perioperative complications, and additional procedures for cases with complications were obtained. RESULTS: In total, 58 patients (43 males, 15 females), 63 fractures were included in this study. Four fractures (6.3%) were Gustilo grade I, 11 fractures (17.5%) were grade II, 34 fractures (54.0%) were grade IIIa, 12 fractures (19.0%) were grade IIIb, and two fractures (3.2%) were grade IIIc. Mean duration of the application of EF was 12.4 days (range, 3-45 days) until conversion to definitive IF. Rates of deep infection and nonunion were both 9.5%, with two cases showing concomitant infection and nonunion. Rates of infection were 8.8% (3/34) in grade IIIa and 25% (3/12) in grade IIIb. Rates of nonunion were 9.1% (1/11) in grade II, 2.9% (1/34) in grade IIIa and 33% (4/12) in grade IIIb. CONCLUSION: Temporary EF for open fracture of the lower limb followed by conversion to IF, as early as soft tissue and general condition permit, may be a safe and effective procedure for patients with lower-limb open fracture of Gustilo grade IIIa or less. LEVEL OF EVIDENCE: Level IV, Case series.

[Current Status and Issues of the Pre-Clinical Training OSCE in Acute Care Nursing Education].

Enabling students to acquire practical skills that can be utilized after graduation has become an agenda for basic nursing education since the start of Japan's "super-aging society" and the sophistication of modern medical treatment. Nursing schools are attempting to introduce the Objective Structured Clinical Examination (OSCE) in an attempt to integrate this important agenda. OSCE has been implemented at our school of nursing since 2014 in the first semester for third year students as a part of the integrated course for clinical training. E-learning has been utilized to help students study for the examination, and, according to students' subjective evaluations, a certain level of effect has been confirmed. However, as we have new agendas for each school year, adjustments need to be made every year. We have made 3 adjustments so far since 2017. In this paper we report on our implementation of the OSCE in the year 2014, evaluations and adjustments to the OSCE in 2014 from the perspectives of 1) learning support, 2) evaluation methods, and 3) the application of the OSCE.

Expression Profiling of MicroRNAs in the Inner Ear of Elderly People by Real-Time PCR Quantification.

The molecular mechanisms underlying age-related hearing loss are unknown, and currently, there is no treatment for this condition. Recent studies have shown that microRNAs (miRNAs) and age-related diseases are intimately linked, suggesting that some miRNAs may present attractive therapeutic targets. In this study, we obtained 8 human temporal bones from 8 elderly subjects at brain autopsy in order to investigate the expression profile of miRNAs in the inner ear with miRNA arrays. A mean of 478 different miRNAs were expressed in the samples, of which 348 were commonly expressed in all 8 samples. Of these, levels of 16 miRNAs significantly differed between young elderly and old elderly subjects. miRNAs, which play important roles in inner ear development, were detected in all samples, i.e., in both young and old elderly subjects, whether with or without hearing loss. Our results suggest that these miRNAs play important roles not only in development, but also in the maintenance of inner ear homeostasis.

Biomechanical Comparison of Short-, Mid-, and Long-Length Proximal Femoral Nails for Femoral Intertrochanteric Fracture (AO/OTA 31A3.3) Fixation.

Introduction: In surgeries for unstable AO/OTA 31A3.3 fractures, surgeons use various lengths of intramedullary nails (IMNs). However, there is insufficient evidence regarding the appropriate nail length for these fractures. This study compared the biomechanical properties of IMNs of different lengths for AO/OTA 31A3.3 fractures. Methods: 30 synthetic femora of AO/OTA 31A3.3 fracture model were randomly assigned to the following three groups: short- (170 mm), mid- (235 mm), and long-length (300 mm) nail groups, and were performed fixation surgery. The translation patterns of the constructs were examined by cyclic testing and compared among three groups. Additionally, changes in the neck-shaft and shaft-nail angles after cyclic testing were evaluated using radiological images. Results: The translation patterns during cyclic loading did not differ among the groups. Conversely, one-way analysis of variance (ANOVA) revealed a significant difference in the neck-shaft angle change (5.8° ± 1.8°, 2.8° ± 1.3°, and 1.9° ± .9° in the short-, mid-, and long-length groups, respectively; P < .001), and post-hoc analysis revealed that the change was greater in the short-length group than in the mid- and long-length groups (P < .001 and P < .001, respectively). Furthermore, one-way ANOVA revealed a significant difference in the shaft-nail angle change (3.1° ± 2.1°, 1.4° ± 1.4°, and .1° ± .6° in the short-, mid-, and long-length groups, respectively; P < .001), and post-hoc analysis revealed that the change was greater in the short-length group than in the mid- and long-length groups (P = .044 and P < .001, respectively). Conclusions: Short-length nails were associated with relevant changes in the neck-shaft and shaft-nail angles in our AO/OTA 31A3.3 fracture model. Thus, the selection of mid- or long-length nails instead of short-length nails might be better in IMN surgery for these fractures to prevent postoperative varus deformity.

Postoperative improvement in patient-reported outcomes after neutral alignment medial open wedge high tibial osteotomy for medial compartment knee osteoarthritis in patients aged ≥70 years versus younger patients.

Purpose: To compare the postoperative clinical and radiological outcomes in patients aged ≥70 years following neutral alignment medial opening-wedge high tibial osteotomy (NA-MOWHTO) for medial compartment knee osteoarthritis (KOA) to those observed in younger patients. Methods: The data of patients who underwent NA-MOWHTO for medial compartment KOA between September 2018 and June 2022 were retrospectively analysed. The patients were categorised into groups Y (<70 years) and O (≥70 years). Age, sex, Kellgren-Lawrence classification, pre- and postoperative mechanical axis, weight-bearing line ratio, medial proximal tibial angle, preoperative Tegner Activity Score and pre- and postoperative Lysholm scores were compared between the groups. Results: Overall, 81 patients (60 and 21 in groups Y and O, respectively) who underwent NA-MOWHTO were included in this study. No significant differences were found in patient characteristics between the two groups, except for the preoperative Tegner Activity Score, which was significantly higher in group Y than in group O (3 [2-4] vs. 2 [2-2], respectively; p = 0.011). The two groups exhibited no significant differences in pre- and postoperative knee alignments. Postoperatively, Lysholm scores improved significantly in both groups without significant differences. Additionally, no correlation was found between age and pre- and postoperative Lysholm scores. Conclusions: The postoperative improvement following NA-MOWHTO for medial compartment KOA is comparable in patients aged ≥70 and younger. Level of Evidence: Level III, Retrospective comparative study.

The need to suspect tension gastrothorax as a cause of obstructive shock in trauma care: A case report.

INTRODUCTION: Traumatic tension gastrothorax is a type of obstructive shock similar to tension pneumothorax. However, tension gastrothorax is not well known among emergency physicians, and no consensus has yet been reached on management during initial trauma care. We present a case of traumatic tension gastrothorax in which tube thoracostomy was performed based solely on clinical findings very similar to tension pneumothorax, followed by emergency laparotomy. PRESENTATION OF CASE: A 24-year-old male motorcyclist was brought to our emergency medical center after being struck by a motor vehicle. He was in respiratory failure and hypotensive shock with findings suggestive of pneumothorax. Although the physical findings were not fully in line with tension pneumothorax, we immediately performed finger thoracostomy. Subsequent radiography revealed left diaphragmatic rupture with hernia. After unsuccessful attempts to decompress the stomach with a nasogastric tube, immediate emergency laparotomy was performed. During the operation, the stomach, which had prolapsed through the ruptured diaphragm into the thoracic cavity, was manually returned to the abdominal cavity. The ruptured diaphragm was repaired with sutures. DISCUSSION: Although distinguishing between tension pneumothorax and tension gastrothorax based on physical examination alone is difficult, tension gastrothorax requires careful attention to avoid intrapleural contamination from gastric injury. In addition, relying solely on stomach decompression with a nasogastric tube or delaying laparotomy could lead to cardiac arrest. CONCLUSION: When tension pneumothorax is suspected during initial trauma care, tension gastrothorax should also be considered as a differential diagnosis and treated with immediate diaphragmatic repair once identified.

Effect of plate design on maintenance of anterior and posterior gaps and posterior tibial slope after cyclic loading in medial open-wedge high tibial osteotomy: A biomechanical study using porcine's tibia.

Purpose: We aimed to investigate whether a plate adapted to the anatomy of the proximal medial porcine's tibia would provide maintenance of the anterior gap (AG), posterior gap (PG) and posterior tibial slope (PTS). Methods: Twenty-seven porcine tibias were biomechanically evaluated by performing MOWHTO and placing TOMOFIX (n = 9), AC plate (n = 9) and TriS (n = 9) anteromedially. Cyclic testing (800 N, 2000 cycles, 0.5 Hz) was performed to investigate the PTS over time for MOWHTO. The particular displacement calculated from the maximum to the minimum point with the load-displacement curve along the mechanical axis during cyclic testing, the final AG and PG changes at the osteotomy site, the increased PTS calculated by subtracting AG from PG after 2000 cycles were compared among the three groups. The displacement was evaluated by repeated-measures analysis of variance (ANOVA), and changes in AG and PG and increased PTS were evaluated by one-way ANOVA. The sample size for α and ß errors were <0.05 and <0.20, and the effect size was 0.64 for one-way ANOVA and 0.49 for repeated-measures ANOVA. Results: There were no significant differences in displacement among the groups. A significant difference was observed in the AG (p = 0.044) and PG (p = 0.0085) changes. There were no significant differences in increased PTS among the groups. Conclusion: When anteromedially placed, the AC plate and TriS resulted in significant maintenance of AG and PG compared with that of TOMOFIX in MOWHTO after cyclic loading. Level of Evidence: Level Ⅳ.

Biomechanical comparisons of plate placement for medial tibial plateau fractures (Schatzker type IV): A biomechanical study using porcine tibias.

INTRODUCTION: Biomechanical studies on medial tibial plateau fractures (MTPFs) (Schatzker classification type IV) are currently few, while studies using locking plates (LPs) placed on medial proximal tibias are unavailable. Hence, we compared the biomechanical properties of plate osteosynthesis at the medial and anteromedial placements using large- and small-fragment LPs in porcine bones. MATERIALS AND METHODS: MTPFs were internally fixed using LPs on 40 porcine tibias. Specimens were equally divided into four groups: medial placement using a large-fragment LP (LPs for the medial (LM) group), anteromedial placement using a large-fragment LP (LAM group), medial placement using a small-fragment LP (SM group), and anteromedial placement using a small-fragment LP (SAM group). The translation patterns of the constructs in each group were examined by cycling loading test (displacement and translation along the mechanical axis at 10-100, 100-500, 500-1000, 1000-1500, and 1500-2000 cycles). Then, articular gaps and step-off changes after 2000 cycles were compared among the four groups. RESULTS: One-way analysis of variance (ANOVA) revealed no significant differences in displacement and translation during cyclic loading. One-way ANOVA followed by post hoc analysis revealed that the anterior gap was lower in LPs for the medial (LM) than in SM (P = 0.029) and SAM (P = 0.0026). The central gap was also lower in LM than in SM (P = 0.042) and SAM (P < 0.001), and it was lower in LAM than in SAM (P = 0.047). Likewise, the posterior gap was lower in LM than in LAM (P = 0.025) and SAM (P < 0.001). Furthermore, the central step-off of SAM was higher than that of LM, LAM, and SM (P < 0.001, P = 0.0014, and P = 0.0077, respectively). The posterior step-off was lower in LM than in SAM and LAM (P = 0.037 and P < 0.001), and it was also lower in SM than in SAM (P = 0.0082). CONCLUSION: Medial LP placement for MTPFs in porcine bones resulted in significantly lower posterior step-offs after cyclic loading than anteromedial placement, and large-fragment LPs for MTPFs caused significantly lower fracture gaps in the central articular after cyclic loading than small-fragment LPs.

Hidden Inferior Vena Cava Injury: A Case of Missed Diagnosis after Preoperative CT and Laparotomy.

BACKGROUND Inferior vena cava (IVC) injury is a potentially fatal injury with a high mortality rate of 34-70%. In cases in which the patient's condition is stable, diagnosis by computed tomography (CT) is the criterion standard. Findings on CT include retroperitoneal hematoma around the IVC, extravasation of contrast medium, and abnormal morphology of the IVC. We report a case of an IVC injury that could not be diagnosed by preoperative CT examination and could not be immediately detected during laparotomy. CASE REPORT A 73-year-old woman had stabbed herself in the neck and abdomen at home using a knife. When she arrived at our hospital, we found a stab wound several centimeters long on her abdomen and a cut approximately 15 cm long on her neck. We activated the massive transfusion protocol because she was in a condition of hemorrhagic shock. After blood transfusion and blood pressure stabilization, contrast-enhanced computed tomography (CT) revealed a small amount of fluid in the abdominal cavity. An otorhinolaryngologist performed successful drainage and hemostasis, and a laparotomy was performed. Gastric injury and mesentery injury of the transverse colon were identified and repaired with sutures. Subsequent search of the retroperitoneum revealed massive bleeding from an injury to the inferior vena cava (IVC). The IVC was repaired. Postoperative progress was good, and she was discharged from the hospital 65 days after her injuries. CONCLUSIONS We experienced a case of penetrating IVC injury, which is a rare trauma. Occult IVC injury may escape detection by preoperative CT examination or during laparotomy.

Risk of peri­implant femoral fracture after cephalomedullary nailing in older patients with trochanteric fractures.

INTRODUCTION: Despite the recent increase in the use of cephalomedullary nails for trochanteric hip fractures, factors that may be associated with peri­implant femoral fracture (PIFF) after cephalomedullary nailing for trochanteric fractures remain unknown. We investigated the factors associated with PIFF after cephalomedullary nailing of trochanteric hip fractures in older patients. METHODS: A nested case-control study was conducted using a database of patients aged ≥65 years who underwent surgery with cephalomedullary nails for trochanteric fractures caused by low-energy trauma during 2005-2021. The cases were defined as patients who developed PIFF after surgery, while controls were patients who did not develop PIFF and who were followed up for ≥3 years after surgery. Four controls were randomly matched to each case for sex and age. First, potential factors associated with PIFF were compared between cases and controls. Second, multivariable conditional logistic regression analysis was employed to assess factors possibly associated with PIFF, controlling for potential confounding factors. RESULTS: Of 1531 patients who underwent surgery with cephalomedullary nails because of trochanteric fractures, we assessed 34 cases and 136 controls (N = 170; mean age 85.7 ± 7 years; and females, 94 %). PIFF was significantly associated with patients having undergone total knee arthroplasty (adjusted odds ratios [95 % confidence intervals], 4.41 [1.16-16.8]) and those with AO/OTA classification 31A3 fracture (A3 fracture) (2.3 [1.12-4.76]), after adjusting for potential confounding factors. CONCLUSIONS: Our results showed that PIFF was more likely to develop among older patients with a clinical history of total knee arthroplasty and A3 fracture. These findings suggest that such patients may require careful follow-up with rigorous assessments after cephalomedullary nailing for trochanteric fractures.