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.

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.

Use of a preoperative 3D templating and proximal lateral tibial fitting patient-specific instrumentation in fixed valgus complex primary total knee arthroplasty for a patient with retaining hardware for internal fixation to treat Schatzker type V tibial plateau fracture: A case report

A 72-year-old female patient with a fixed valgus knee deformity due to a Schatzker type V tibial plateau fracture treated with bilateral locking plates 8 years ago was admitted to our clinic with complaints of chronic pain and knee instability when walking. Radiographs revealed Kellgren-Lawrence Classification grade 4 knee osteoarthritis and 20.5° of valgus knee deformity. She was treated with three-dimensional templating and proximal lateral tibial fitting patient-specific instrumentation-assisted mechanically aligned posterior sacrificing total knee arthroplasty with minimal removal of the retained hardware for the internal fixation of the tibial plateau fracture via a lateral approach, resulting in a favorable clinical outcome. The use of proximal lateral tibial fitting patient-specific instrumentation in fixed valgus complex primary total knee arthroplasty for patients with retaining hardware for internal fixation to treat tibial plateau fractures is considered a treatment option to decrease surgical invasion.

Risk of peri‑implant 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 peri‑implant 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.

Epidemiology of fragility fracture of the pelvic ring: a regional population-based study in Northern Japan

Using a regional population-based dataset in Japan, we identified the epidemiological characteristics of patients with fragility fractures of the pelvic ring. The incidence rate was 35.5-121.2 per 100,000 population/year. Age-specific incidence increased after 75 years. This fracture is associated with worse prognosis in terms of walking function and life expectancy.

PURPOSE

Fragility fracture of the pelvic ring (FFP) is common among older patients; however, little information is available on the epidemiology of FFP worldwide. We aimed to identify the epidemiological characteristics of patients with FFP using a regional population-based dataset in Japan.

METHODS

This descriptive epidemiologic study analyzed data obtained from clinical information of patients diagnosed with FFP from January 1, 2011 through December 31, 2020 at a regional dominant hospital in Japan. We calculated the crude and age-adjusted annual incidences and the age-specific incidence and described epidemiological date, injury characteristics, walking ability before and after FFP, and mortality. Additionally, we investigated factors associated with walking ability.

RESULTS

We identified 66 FFP patients, of whom 55 (83.3%) were female, with a mean age of 82.2 years. The crude annual incidence of FFP ranged from 35.5-121.2 per 100,000 population/year during the study period. The age-specific incidence of FFP increased after 75 and 80 years in females and males, respectively. In total, 44.4% of patients had declines in walking ability 1 year after their FFP injuries. Patients with declining walking ability were significantly older (p < 0.01), and age ≥ 80 years was significantly associated with the decline in walking ability (p < 0.01). The 1- and 5-year mortality rates were 15.4% and 39.9%, respectively.

CONCLUSION

The incidence rate of FFP was 35.5-121.2 per 100,000 population/year. Age-specific incidence of FFP increased after 75 years. Our results indicate that FFP is associated with worse prognosis of walking function and life expectancy.

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.

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.

Effect of plate position on tibial displacement and posterior tibial slope after cyclic loading in medial open wedge high tibial osteotomy: A biomechanical study using porcine tibia

BACKGROUND

Medial open wedge high tibial osteotomy is currently the most common osteotomy, but its complication is an increased posterior tibial slope over time. However, no study has clarified whether the plate position of medial open wedge high tibial osteotomy could reduce the increase in posterior tibial slope after cyclic loading.

METHODS

Fourteen porcine bones were biomechanically evaluated by performing medial open wedge high tibial osteotomy and placing TOMOFIX medially and anteromedially. Cyclic testing was performed to investigate the posterior tibial slope over time for medial open wedge high tibial osteotomy with medial or anteromedial plate. The displacement along the mechanical axis during cyclic testing from 10 to 100th, 100-500th, 500-1000th, 1000-1500th, and 1500-2000th cycles, and changes in anterior and posterior gaps after 2000 cycles were compared between plate position.

FINDINGS

There were no significant differences in displacement. A significant difference was found in posterior gap changes (-0.20 ± 0.84 mm in group of using medial plate, 1.07 ± 0.82 mm in group of using anteromedial plate) (P = 0.014), but none was found in anterior gap changes.

INTERPRETATION

Medial plate placement in medial open wedge high tibial osteotomy resulted in significantly less increased posterior tibial slope than anteromedial plate placement after cyclic loading.

Anterior cruciate ligament reconstruction with retained internal fixation hardware for treating Schatzker type V tibial plateau fracture: Two case reports

Despite the high incidence of anterior cruciate ligament injury in patients with tibial plateau fractures, we found no reports about anterior cruciate ligament reconstruction with retained internal fixation hardware for these fractures. Herein, we report 2 male patients with Schatzker type V tibial plateau fractures and describe the use of retained hardware for internal fixation in tibia. The patients underwent anterior cruciate ligament reconstruction using outside-in technique for the femoral tunnel. Throughout the follow-up, no radiological symptoms of suspected knee osteoarthritis were observed. Accordingly, surgical intervention can be reduced by creating an independent femoral tunnel.

The effectiveness of dance movement therapy for individuals with Down syndrome: a pilot randomised controlled trial

BACKGROUND

Individuals with Down syndrome (DS) exhibit deficits in static and dynamic balance abilities and maladaptive functions. This study aimed to determine the effectiveness of dance movement therapy (DMT) group intervention in individuals with DS.

METHODS

The 31 participating individuals with DS, aged 5-29 years, were randomly divided into intervention (n = 16) and control (n = 15) groups. Posturography was used for static balance measurement, timed up and go test for dynamic balance measurement and the Achenbach System of Empirically Based Assessment (ASEBA) questionnaire for adaptive function and behavioural problem measurement in participants before and after the DMT interventions. The intervention group underwent 60-min DMT intervention once a week for 10 times, while the control group had usual daily activities.

RESULTS

The results revealed a statistically significant difference and large effect sizes in dynamic balance [(f(1, 29) = 4.52, P = 0.04, η_p   ² = 0.14)] in the intervention group compared with the control group. There were no statistically significant differences in static balance and ASEBA scores between the groups.

CONCLUSIONS

This study found that the DMT interventions helped to improve the dynamic balance in individuals with DS.

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.

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.

Characterization of a half-wave plate for cosmic microwave background circular polarization measurement with POLARBEAR

A half-wave plate (HWP) is often used as a modulator to suppress systematic error in the measurements of cosmic microwave background (CMB) polarization. A HWP can also be used to measure circular polarization (CP) through its optical leakage from CP to linear polarization. The CP of the CMB is predicted from various sources, such as interactions in the Universe and extension of the standard model. Interaction with supernova remnants of population III stars is one of the brightest CP sources. Thus, the observation of the CP of CMB is a new tool for searching for population III stars. In this paper, we demonstrate the improved measurement of the leakage coefficient using the transmission measurement of an actual HWP in the laboratory. We measured the transmittance of linearly polarized light through the HWP used in Polarbear in the frequency range of 120-160 GHz. We evaluate the properties of the HWP by fitting the data with a physical model using the Markov Chain Monte Carlo method. We then estimate the band-averaged CP leakage coefficient using the physical model. We find that the leakage coefficient strongly depends on the spectra of CP sources. We thus calculate the maximum fractional leakage coefficient from CP to linear polarization as 0.133 ± 0.009 in the Rayleigh-Jeans spectrum. The nonzero value shows that Polarbear has a sensitivity to CP. Additionally, because we use the bandpass of detectors installed in the telescope to calculate the band-averaged values, we also consider systematic effects in the experiment.

Search for the Pair Production of Dark Particles X with K_{L}^{0}→XX, X→γγ

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110  MeV/c^{2} and 210-240  MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

Revision surgery in a middle-aged patient with pertrochanteric fracture nonunion due to wedge effect caused by cephalomedullary nail: A case report

Trochanteric femur fractures have traditionally been treated surgically with compression hip screws or cephalomedullary nails. With the increasing use of cephalomedullary nails, potential complications from this technique have surfaced. One of them is the potential for varus malreduction of trochanteric femur fractures, known as the "wedge effect", which is the distraction of fracture fragments generated during reamer and nail passage resulting in varus malalignment at the neck-shaft angle. Although trochanteric nonunion in the non-elderly is exceedingly rare, we experienced one such case after nailing due to the wedge effect that was subsequently successfully treated with a compression hip screw without bone grafting. Therefore, in the case of stable pertrochanteric fractures (AO/OTA 31A1) in younger patients, compression hip screw surgery may be the better choice of initial surgery to avoid later nonunion.

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.

Spinal cord injury without radiological abnormality due to a fall while using an abdominal roller: A report of two cases

Background

In recent years, various home-use health devices have gained popularity. The abdominal roller is one of these. Spinal cord injury without radiological abnormality is known to occur even with relatively minor injuries, but there are few reports of such injuries caused by a roller.

Case Presentation

Two cases of spinal cord injuries caused by a roller are reported. In both cases, injuries occurred during the standing rollout by a patient in an inebriated state, and the patients were rushed to an emergency department.

Conclusion

Because the use of abdominal rollers may result in extremely serious disabilities, it is necessary to emphasize the appropriate use of such equipment.

Biomechanical Comparisons of Trochanteric Hip Fracture Fixation Using Short-, Mid-, and Long-Length Proximal Femoral Nails

Introduction

For trochanteric hip fractures, proximal femoral nails (PFNs) have been frequently used for surgical treatment. No study has clarified whether length of the nail affected the wiper motion; the repetitive motion of the distal nail inside canal after surgery.

Methods

Thirty synthetic femora were used to biomechanically evaluate construct lateral angular movement of 3 different lengths of PFN [TFN-ADVANCED Proximal Femoral Nailing System (TFNA) 170 (short-length), 235 (mid-length), and 300 (long-length) mm] constructs for the fixation of stable pertrochanteric fractures. Cyclic testing and radiological evaluation were performed to investigate the loosening patterns in 3 different fixation constructs. Migration along the mechanical axis during the cyclic testing from 1-100^th, 100-500^th, 500-1000^th, 1000-1500^th, and 1500-2000^th cycles was compared between TFNA lengths. Also, before and after cycling changes in tip to apex distance, angulation of fracture line, and lateral angular movement of the distal stem inside the canal were compared between TFNA lengths.

Results

Migration along the mechanical axis during cyclic loading, plus changes after cycling in tip to apex distance, and fracture line angulation did not differ between TFNA lengths for the fixation of stable intertrochanteric fracture model using synthetic femora. Conversely, one-way analysis of variance revealed a significant difference in lateral angular movement of the distal stem inside the canal after cyclic testing between groups (1.4 ± 1.6°, .21 ± .35°, and .26 ± .57° in 170-mm short nail, 235-mm middle nail, and 300-mm long nail, respectively; P = .026), and post-hoc analysis also revealed that middle nail yielded significantly less lateral angular movement compared with short nail (P = .047) but did not significantly differ from the long nail.

Conclusions

Mid-length TFNA for the fixation of stable trochanteric hip fracture model using synthetic femora resulted in significantly smaller lateral angular movement of the distal stem after cyclic loading.

Characterization and Structure of Alternatively Spliced Transcript Variant of Human Intestinal Alkaline Phosphatase (ALPI) Gene

Intestinal-type alkaline phosphatase (IAP) is expressed at a high concentration in the brush border membrane of intestinal epithelial cells and is known to be a gut mucosal defense factor. In humans, a single gene (ALPI) for IAP has been isolated, and its transcription produces two kinds of alternatively spliced mRNAs (aAug10 and bAug10). Recently, we discovered that vitamin D up-regulated the expression of both types of human IAP alternative splicing variants in Caco-2 cells. However, the functional difference of protein encoded by the mRNA variants has remained elusive. In the present study, we aimed to provide further insight into the characterization and structure of IAP isoforms. To analyze the protein translated from the ALPI gene, we constructed two kinds of cDNA expression plasmids (aAug10 and bAug10), and the transfected cells were homogenized and assayed for alkaline phosphatase (ALP) activity. We also designed the homology-modeled 3D structures of the protein encoded by the mRNA variants (ALPI-aAug10 and ALPI-bAug10). The levels of ALP activity of COS-1 cells transfected with the aAug10 plasmid were increased significantly, while cells transfected with the bAug10 plasmid had undetectable ALP activity. The homology-modeled 3D structures revealed that the variant bAug10 lacks the central N-terminal α-helix and residue corresponding to Asp-42 of ALPI-aAug10 near the active site. This is the first report on the characterization and structure of alternatively spliced transcript variants of the human ALPI gene. Further studies on the regulation of aAug10 and/or bAug10 mRNA expression may identify novel physiological functions of IAP.

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.

Evaluation of reduction efficiencies of pepper mild mottle virus and human enteric viruses in full-scale drinking water treatment plants employing coagulation-sedimentation-rapid sand filtration or coagulation-microfiltration

Here, we evaluated the reduction efficiencies of indigenous pepper mild mottle virus (PMMoV, a potential surrogate for human enteric viruses to assess virus removal by coagulation-sedimentation-rapid sand filtration [CS-RSF] and coagulation-microfiltration [C-MF]) and representative human enteric viruses in four full-scale drinking water treatment plants that use CS-RSF (Plants A and B) or C-MF (Plants C and D). First, we developed a virus concentration method by using an electropositive filter and a tangential-flow ultrafiltration membrane to effectively concentrate and recover PMMoV from large volumes of water: the recovery rates of PMMoV were 100% when 100-L samples of PMMoV-spiked dechlorinated tap water were concentrated to 20 mL; even when spiked water volume was 2000 L, recovery rates of >30% were maintained. The concentrations of indigenous PMMoV in raw and treated water samples determined by using this method were always above the quantification limit of the real-time polymerase chain reaction assay. We therefore were able to determine its reduction ratios: 0.9-2.7-log10 in full-scale CS-RSF and 0.7-2.9-log10 in full-scale C-MF. The PMMoV reduction ratios in C-MF at Plant C (1.0 ± 0.3-log10) were lower than those in CS-RSF at Plants A (1.7 ± 0.5-log10) and B (1.4 ± 0.7-log10), despite the higher ability of MF for particle separation in comparison with RSF owing to the small pore size in MF. Lab-scale virus-spiking C-MF experiments that mimicked full-scale C-MF revealed that a low dosage of coagulant (polyaluminum chloride [PACl]) applied in C-MF, which is determined mainly from the viewpoint of preventing membrane fouling, probably led to the low reduction ratios of PMMoV in C-MF. This implies that high virus reduction ratios (>4-log10) achieved in previous lab-scale virus-spiking C-MF studies are not necessarily achieved in full-scale C-MF. The PMMoV reduction ratios in C-MF at Plant D (2.2 ± 0.6-log10) were higher than those at Plant C, despite similar coagulant dosages. In lab-scale C-MF, the PMMoV reduction ratios increased from 1-log10 (with PACl [basicity 1.5], as at Plant C) to 2-4-log10 (with high-basicity PACl [basicity 2.1], as at Plant D), suggesting that the use of high-basicity PACl probably resulted in higher reduction ratios of PMMoV at Plant D than at Plant C. Finally, we compared the reduction ratios of indigenous PMMoV and representative human enteric viruses in full-scale CS-RSF and C-MF. At Plant D, the concentrations of human norovirus genogroup II (HuNoV GII) in raw water were sometimes above the quantification limit; however, whether its reduction ratios in C-MF were higher than those of PMMoV could not be judged since reduction ratios were >1.4-log10 for HuNoV GII and 2.3-2.9-log10 for PMMoV. At Plant B, the concentrations of enteroviruses (EVs) and HuNoV GII in raw water were above the quantification limit on one occasion, and the reduction ratios of EVs (>1.2-log10) and HuNoV GII (>1.5-log10) in CS-RSF were higher than that of PMMoV (0.9-log10). This finding supports the usefulness of PMMoV as a potential surrogate for human enteric viruses to assess virus removal by CS-RSF.

Total knee arthroplasty, following application of Taylor Spatial Frames to treat knee osteoarthritis with severe tibia extraarticular deformity due to fracture malunion: A case report

Obtaining alignment during end-stage knee osteoarthritis with extraarticular deformities has always been challenging. Therefore, we report a case of total knee arthroplasty, following the application of Taylor Spatial Frame to treat knee osteoarthritis with severe tibia extraarticular deformity due to a proximal tibia fracture injury for more than 50 years ago. First, proximal tibial opening wedge osteotomy was conducted below the patellar tendon insertion from the anterior to the posterior direction to correct the deformity in multiple planes gradually. Then, osteotomy was done to restore both the varus and recurvatum deformities. Finally, Taylor Spatial Frame was used as a virtual hinge, with gradual adjustments to correct the deformity. Afterward, patient-specific instrumentation-assisted total knee arthroplasty was conducted after correcting the extraarticular deformity. During the two-year follow-up, no superficial and deep infection occurred, and his Oxford Knee Score had improved from 32 to 19 out of 48 at the time of the latest follow-up. Moreover, the patient walked using a one-hand clutch without protective limping. Hence, patient-specific instrumentation-assisted total knee arthroplasty, following proximal tibial osteotomy with Taylor Spatial Frame, should be considered a treatment option for patients with knee osteoarthritis having severe proximal tibia extraarticular deformity.

Blast injury of the finger caused by mobile battery explosion: A case report

Lithium-ion batteries can cause several types of injuries upon explosion due to misfire. We report a case in which a mobile battery explosion resulted in high-pressure injection of metal debris into a small entry point on the skin creating puncture wounds on a patient's index finger, necessitating surgical intervention for massive debridement. A healthy 45-year-old, right-hand-dominant woman presented to the emergency department 4 h after a mobile battery had exploded in her left hand, causing burns to the left index finger. The battery had exploded due to misfire because the patient had accidentally hit it with a hammer. Radiographs of the index finger demonstrated foreign material extending from the fingertip to the ulnar proximal phalanx along the flexor tendon sheath, which was consistent with a high-pressure injection injury. She underwent semiurgent incision, irrigation, and debridement of the left index finger the day after the injury. The wound healed uneventfully within a month. At the 6-month follow-up, the palm-to-tip distance was 1 cm, and sensation at the tip was recovered. Compositional analysis of the debris revealed that the two major elements were aluminum and nickel (both less than 10%); lithium constituted less than 1% of the debris, a level deemed safe in humans. The protocol of semiurgent incision, irrigation, and debridement was safe and effective in the treatment of the injection injury caused by the mobile battery explosion.

Nemolizumab plus topical agents in patients with atopic dermatitis (AD) and moderate-to-severe pruritus provide improvement in pruritus and signs of AD for up to 68 weeks: results from two phase III, long-term studies

Background

Interleukin (IL)‐31 affects the inflammatory response, is involved in epidermal barrier disruption in atopic dermatitis (AD) and plays a key role in pruritus. Nemolizumab, a humanized monoclonal antibody against IL‐31 receptor A, reduced pruritus in patients with AD after a 16‐week administration period.

Objectives

To examine the long‐term effectiveness and safety of nemolizumab in patients aged ≥ 13 years with AD and inadequately controlled moderate‐to‐severe pruritus.

Methods

In two long‐term phase III studies, nemolizumab 60 mg every 4 weeks (Q4W) was administered subcutaneously, concomitantly with topical treatments. Study‐JP01 patients received double‐blind nemolizumab or placebo for 16 weeks, and then entered a 52‐week extension period in which all patients received nemolizumab (nemolizumab/nemolizumab and placebo/nemolizumab groups). Study‐JP02 patients received nemolizumab for 52 weeks. Both studies included an 8‐week follow‐up period.

Results

Study‐JP01 nemolizumab/nemolizumab and placebo/nemolizumab, and Study‐JP02 nemolizumab groups comprised 143, 72 and 88 patients, respectively. In the nemolizumab/nemolizumab group, there were clinically meaningful improvements from the start of treatment to week 68 in the pruritus visual analogue scale (66% decrease) and Eczema Area and Severity Index (78% decrease). Quality of life (QoL) indicators improved after the first nemolizumab dose; improvements were maintained during the follow‐up period. The long‐term safety profile was consistent with previous studies, with no unexpected late‐onset adverse events.

Conclusions

Nemolizumab 60 mg Q4W with concomitant topical treatments in patients with AD and inadequately controlled moderate‐to‐severe pruritus produced a continuous improvement in pruritus, signs of AD, and QoL for up to 68 weeks, with a favourable safety profile.

P–017 The maintenance of testicular architecture and germ cell in adult testis tissue under organ culture condition based on the gas-liquid interface method

Study question

Can the gas-liquid interface organ culture system that achieved in vitro spermatogenesis in mice also support in vitro spermatogenesis in human adult testis?

Summary answer

Although the progression of spermatogenesis was not observed, germ cells were maintained without the degeneration of the architecture in both fresh and cryopreserved testicular tissues.

What is known already

Although the research on in vitro spermatogenesis have been conducted for 100 years, only the organ culture system using gas-liquid interface method achieved in vitro spermatogenesis in mice. It has not been verified whether this culture system can be applied to other mammals including humans and induce spermatogenesis.

Study design, size, duration

Testicular tissue was obtained from the transgender patients receiving sex reassignment surgery. Testicular specimens were either immediately processed for cultivation or cryopreserved, using a vitrification freezing protocol. Organ culture of testicular fragments was performed in three different media for a maximum period of 3 weeks to evaluate the short-term changes in the cultured tissues (viability, proliferation and maintenance of germ and somatic cells).

Participants/materials, setting, methods

Fresh and cryopreserved-thawed testis fragments (1–2 mm3) were cultured using the organ culture system in alpha-MEM with knock-out serum replacement (K group), alpha-MEM with lipid-rich BSA (A group) and DMEM with FBS (D group). Luteinizing hormone, follicle stimulating hormone and testosterone were supplemented. The number of germ cells (using DDX4), proliferative activity of germ cells (using EdU assay) and intratubular cell apoptosis (by TdT-mediated dUTP Nick End Labeling) were evaluated by immunohistochemical staining weekly.

Main results and the role of chance

The architecture of the seminiferous tubules was maintained until the second week of culture in both the fresh and the cryopreserved culture group. The number of DDX4-positive germ cells per seminiferous tubule in groups D, K, and A was 49 ± 24, 55 ± 21, 50 ± 26 cells/tubule in 1 day, 32 ± 13, 42 ± 7, 36 ± 21 cells/tubule in 1week, respectively. The numbers gradually decreased to 26 ± 8, 24 ± 6 and 27 ± 18 cells/tubule, in 2 weeks, respectively, with no difference among the groups. The number of intratubular EdU-positive cells of groups D, K, and A was 0.2 ± 0.2, 2.8 ± 2.1, 1.1 ± 0.8 cells/tubule at 1 day, 0.1 ± 0.2, 0.5 ± 0.6, 0.3 ± 0.6 cells/tubule at 1 week, respectively. The values were 0.01, 0.05, and 0.03 at 2 weeks. Thus, EdU-positive cells drastically decreased from the first week of culture. The number of DDX4-positive germ cells and the intratubular EdU-positive cells in the cryopreserved culture group was not different from that in the fresh culture group.

Limitations, reasons for caution

Current organ culture systems are incomplete, being unable to induce human in vitro spermatogenesis. Further research is needed to improve culture condition with the aim of producing fertile sperm of infertile adult male patients.

Wider implications of the findings: Our organ culture system could maintain testis structure and germ cells. By using the testis tissues of the transgender patients, which are available with their consent, we will promote the investigation of the culture condition necessary for germ cell proliferation and differentiation.

Trial registration number

Grant-in-Aid for Scientific Research on Innovative Areas 18H05546, Grant-in-Aid for Young Scientists (A) 17H05098 and Takeda Science Foundation

Legg-Calvé-Perthes disease following Ender nail fixation of a pediatric femoral fracture

Introduction and importance

Legg–Calvé–Perthes disease (LCPD) sometimes occur in children, however it is difficult to diagnose it at the early stage especially in the cases there are no complaints of symptoms. Femoral shaft fractures in children cause various complications such as leg-length discrepancy, nonunion and malunion, refracture, and osteonecrosis of the femoral head. We presented a rare case in which a pediatric patient developed LCPD after femoral shaft fracture.

Case presentation

A healthy 8-year-old boy sustained a left femoral diaphyseal fracture following a pedestrian car accident. Fixation was achieved using retrograde Ender nails; bone union was confirmed at 3 months postoperatively, and the Ender nails were removed at 8 months postoperatively without any problems. Unfortunately, the morphological change of the ipsilateral femoral head and subtle symptoms were missed until the femoral head collapsed. LCPD was successfully treated with intertrochanteric varus osteotomy, which achieved a good clinical result.

Clinical discussion

Although the reason for the ipsilateral LCPD after the femoral shaft fracture is unclear, this case highlights the need for close postoperative follow-up of pediatric femoral fractures resulting from high-energy trauma to prevent the misdiagnosis of this coincidental complication.

Conclusion

This case report describes a missed ipsilateral LCPD after a femoral diaphyseal fracture caused by high-energy trauma. Close postoperative follow-up with a detailed assessment and vigilant interpretation of postoperative radiography is imperative to avoid delayed/missed diagnosis of conditions for which early management may provide better outcomes.

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Legg–Calvé–Perthes disease after femoral shaft fracture

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Close postoperative radiographic follow-up is necessary to avoid misdiagnosis.

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Legg–Calvé–Perthes disease was successfully treated with intertrochanteric varus osteotomy.

Evaluation of the stability of Yamakagashi (Rhabdophis tigrinus) Equine Antivenom after 20 years storage

In 2000, an equine Yamakagashi (Rhabdophis tigrinus) antivenom (Lot 0001) was testmanufactured as an unapproved drug for treatment of Yamakagashi bites. It was stocked on the premise of super-legal use from the viewpoint of emergency health crisis management. The antivenom showed a strong neutralizing ability against the hemorrhagic and coagulation activity of the Yamakagashi venom in its potency test. One vial of the antivenom can effectively neutralize at least about 4 mg of Yamakagashi venom. Its efficacy has also been confirmed in patients with severe cases of R. tigrinus bite that has been used in emergency. In 2020, this antivenom (Lot 0001) has reached 20 years after its production. To evaluate the integrity and potency of the antivenom, quality control, safety and potency tests had been conducted almost every year since 2012. Physical and chemical tests (property test, moisture content test, insoluble foreign matter test, osmotic pressure ratio test, pH test, protein content test, endotoxin test, sterility test) of the antivenom, showed no significant changes throughout the years, when compared to the results immediately after its production in 2000. All the parameters measured were also within the standard values. In animal safety tests (test for absence of toxicity and pyrogen), there was no change in the test results during the storage period and no abnormalities were observed. The potency test (anti-coagulant activity) after 20 years of the product, showed the same potency as those recorded immediately after production. Therefore, in all of the stability monitoring tests conducted so far, the product did not show any significant change compared to the results immediately after production. This confirms the stability of the product during the stockpiling period to the present, that is, 20 years after production.

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.

Study of the K_{L}→π^{0}νν[over ¯] Decay at the J-PARC KOTO Experiment

The rare decay K_{L}→π^{0}νν[over ¯] was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05_{stat}±0.66_{syst})×10^{-10}, three candidate events were observed in the signal region. After unveiling them, contaminations from K^{±} and scattered K_{L} decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10^{-9} on the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level.

A cryogenic continuously rotating half-wave plate mechanism for the POLARBEAR-2b cosmic microwave background receiver

We present the design and laboratory evaluation of a cryogenic continuously rotating half-wave plate (CHWP) for the POLARBEAR-2b (PB-2b) cosmic microwave background receiver, the second installment of the Simons Array. PB-2b will observe at 5200 m elevation in the Atacama Desert of Chile in two frequency bands centered at 90 GHz and 150 GHz. In order to suppress atmospheric 1/f noise and mitigate systematic effects that arise when differencing orthogonal detectors, PB-2b modulates linear sky polarization using a CHWP rotating at 2 Hz. The CHWP has a 440 mm clear aperture diameter and is cooled to ≈50 K in the PB-2b receiver cryostat. It consists of a low-friction superconducting magnetic bearing and a low-torque synchronous electromagnetic motor, which together dissipate <2 W. During cooldown, a grip-and-release mechanism centers the rotor to <0.5 mm, and during continuous rotation, an incremental optical encoder measures the rotor angle with a noise level of 0.1 μrad/Hz. We discuss the experimental requirements for the PB-2b CHWP, the designs of its various subsystems, and the results of its evaluation in the laboratory. The presented CHWP has been deployed to Chile and is expected to see first light on PB-2b in 2020 or 2021.

Congenital Membranous Stapes Footplate Producing Episodic Pressure-Induced Perilymphatic Fistula Symptoms

Introduction: Recent third window syndrome studies have revealed that the intact bony labyrinth and differences in the stiffness of the oval and round windows are essential for proper cochlear and vestibular function. Herein we report a patient with a congenital dehiscence of the right stapes footplate. This dehiscence caused long-standing episodic pressure-induced vertigo (Hennebert sign). At the time of presentation, her increased thoracic pressure changes induced the rupture of the membranous stapes footplate. Perilymph leakage was confirmed by imaging and a biochemical test [perilymph-specific protein Cochlin-tomoprotein (CTP) detection test].

Case Report: A 32-year-old woman presented with a sudden onset of right-sided hearing loss and severe true rotational vertigo, which occurred immediately after nose-blowing. CT scan showed a vestibule pneumolabyrinth. Perilymphatic fistula (PLF) repair surgery was performed. During the operation, a bony defect of 0.5 mm at the center of the right stapes footplate, which was covered by a membranous tissue, and a tear was found in this anomalous membrane. A perilymph-specific protein CTP detection test was positive. The fistula in the footplate was sealed. Postoperatively, the vestibular symptoms resolved, and her hearing improved. A more detailed history revealed that, for 15 years, she experienced true rotational vertigo when she would blow her nose. After she stopped blowing her nose, she would again feel normal.

Discussion: There is a spectrum of anomalies that can occur in the middle ear, including the ossicles. The present case had a dehiscence of the stapes, with a small membranous layer of tissue covering a bony defect in the center of the footplate. Before her acute presentation to the hospital, this abnormal footplate with dehiscence induced pathological pressure-evoked fluid-mechanical waves in the inner ear, which resulted in Hennebert sign. When patients have susceptibility (e.g., weak structure) to rupture, such as that identified in this case, PLF can be caused by seemingly insignificant events such as nose-blowing, coughing, or straining.

Conclusion: This case demonstrates that PLF is a real clinical entity. Appropriate recognition and treatment of PLF can improve a patient's condition and, hence, the quality of life.

Clinical Outcome of Mid-Length Proximal Femoral Nail for Patients With Trochanteric Hip Fractures: Preliminary Investigation in a Japanese Cohort of Patients More Than 70 Years Old

Introduction:

The TFN-ADVANCED Proximal Femoral Nailing System (TFNA) 235 mm (DePuySynthes) and Proximal Femoral Nail Antirotation (PFNA)-II 240 mm (DePuySynthes) were developed to obtain better stability for patients with trochanteric hip fractures without increasing surgical time and amount of blood loss. However, there are currently no studies concerning clinical and radiological outcomes of patients treated using these proximal femoral nails (PFNs) that have been performed in the Japanese population. The aim of this study was to retrospectively evaluate the clinical outcomes associated with 235 to 240 mm PFNs for Japanese patients >70 years old with trochanteric hip fractures who could walk independently before the injury.

Materials and Methods:

This study involved a retrospective analysis of data on trochanteric hip fracture patients who had undergone internal fixation from March 2016 to June 2018. The inclusion criteria were patients >70 years old with trochanteric hip fractures who could walk independently before the injury and were followed up for ≥3 months after surgery. Initially, 124 patients were identified, but 33 of these were excluded because other implants were used for internal fixation. Of the remaining 91 patients in whom PFNs were used at the time of internal fixation who were included for the perioperative evaluation, 66 patients followed up for ≥3 months were included in the clinical evaluations.

Results:

The average surgical time was 56.8 ± 19.6 minutes (range, 23-123 minutes). The average blood loss was 89 ± 41 mL (range, 0-245 mL). The union rate was 98%.

Discussion:

There were no cases of nail jamming, and all nails were successfully inserted below the end of the distal isthmus without additional reaming to dilate the canal.

Conclusions:

Proximal femoral nails were a useful implant in Japanese elderly patients with trochanteric hip fractures and gave comparable clinical outcomes despite the femoral length being short and occurrence of intensive bowing.

Internal Delensing of Cosmic Microwave Background Polarization B-Modes with the POLARBEAR Experiment

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

Management of infected non-union of subtrochanteric fracture: Two cases

Infected non-union of subtrochanteric fractures is challenging to treat. We experienced two cases and had good clinical results. Treatment strategy comprised debridement without hesitation after considering later limb lengthening; insertion of the proximal lateral bone edge spike into the distal bone marrow cavity until achieving medial-side bony contact and holding good alignment to compensate for the medial-side bone loss, according to the modified Dimon method; and internal fixation with an angled plate in the decubitus position. The angle of the angled plate should be directed toward the abundant cancellous bone using preoperative computed tomography. Residual limb shortening after ORIF was improved by limb lengthening.

Open reduction and internal fixation using a locking compression plate as treatment for subtrochanteric fracture in two patients with osteopetrosis

INTRODUCTION

Osteopetrosis is a heritable disease characterized by the dysfunction of osteoclasts, resulting in decreased bone resorption and increased bone density. Fractures are a common complication of osteopetrosis, which are challenging for orthopedic surgeons to treat because the condition renders canal reaming and screw placement difficult.

MATERIALS AND METHODS

Data of patients with osteopetrosis from 2011 to 2019, which were available from an electronic medical database, were retrospectively analyzed. Inclusion criteria were patients with osteopetrosis having subtrochanteric fractures who were followed up for at least 72 months; 2 patients were identified.

RESULTS

Case 1 was a 38-year-old male and Case 2 was a 79-year-old female. Both had left subtrochanteric fractures identified using X-ray that were classified as AO 32-A3.3 and AO 31-A3.3 and treated by open reduction and internal fixation using a reversed distal femoral locking compression plate (DePuy Synthes, Obedors, Switzerland). For Case 1, fracture union was confirmed 8 months after surgery and the patient recovered the ability to walk independently using a cane, which was consistent with his pre-injury functioning. Complications were not observed during the 7-year follow-up period. For Case 2, fracture union was confirmed 9 months after surgery. She was able to walk using a crutch, which was consistent with her pre-injury functioning. Complications were not observed during the 8-year follow-up period.

CONCLUSIONS

We propose that there is a greater need for anatomic reduction when treating subtrochanteric fracture in patients with osteopetrosis. In order to address this issue, we recommend the surgical option involving internal fixation with a locking plate that is conducted in the lateral decubitus position. This position could benefit patients with osteopetrosis having proximal femoral fractures because anatomic reduction and plate stabilization minimize the potential injury to the abductor mechanism.

Tissue non-specific alkaline phosphatase activity and mineralization capacity of bi-allelic mutations from severe perinatal and asymptomatic hypophosphatasia phenotypes: Results from an in vitro mutagenesis model

BACKGROUND

Hypophosphatasia (HPP) is an inherited metabolic bone disease characterized by reduced mineralization due to mutations in the tissue non-specific alkaline phosphatase (ALPL) gene. HPP is clinically variable with extensive allelic heterogeneity in the ALPL gene. We report the findings of in vitro functional studies following site-directed mutagenesis in bi-allelic mutations causing extreme clinical phenotypes; severe perinatal and asymptomatic HPP.

AIMS

Elucidate genotype-phenotype correlation using in vitro functional studies and 3 dimensional (3D) ALP modelling.

METHODS

Clinical, biochemical and radiological features were recorded in two children with extreme HPP phenotypes: Subject 1 (S1): Perinatal HPP with compound heterozygous mutations (c.110T>C; c.532T>C); Subject 2 (S2): asymptomatic with homozygous missense mutation (c.715G>T). Plasmids created for mutants 1 c.110T>C (L37P), 2 c.532T>C (Y178H) and 3 c.715G>T (D239Y) using in vitro mutagenesis were transfected into human osteosarcoma (U₂OS) cells and compared to wildtype (WT) and mock cDNA. ALP activity was measured using enzyme kinetics with p-nitrophenylphosphate. Mineral deposition was evaluated photometrically with Alizarin Red S staining after culture with mineralization medium. Western blot analysis was performed to identify the mature type protein expression (80 kDa). Mutations were located on a 3D ALP model. Co-transfection was performed to identify dominant negative effect of the mutants.

RESULTS

Phenotype: S1, had typical perinatal HPP phenotype at birth; extremely under-mineralized bones and pulmonary hypoplasia. S2, diagnosed incidentally by laboratory tests at 4 years, had normal growth, development, dentition and radiology. All S2's siblings (3 homozygous, 1 heterozygous) were asymptomatic. All subjects had typical biochemical features of HPP (low ALP, high serum pyridoxal-5'-phosphate), except the heterozygous sibling (normal ALP). Functional assay: Mutants 1 and 2 demonstrated negligible ALP activity and mineralization was 7.9% and 9.3% of WT, respectively. Mutant 3 demonstrated about 50% ALP activity and 15.5% mineralization of WT. On Western blot analysis, mutants 1 and 2 were detected as faint bands indicating reduced expression and mutant 3 was expressed as mature form protein with 50% of WT expression. Mutant 1 was located near the Glycosylphosphatidylinositol anchor, 2 at the core structure of the ALP protein and 3 at the periphery of the protein structure. Co-transfection did not reveal a dominant negative effect in any of the mutants.

CONCLUSION

Our findings expand the current knowledge of functional effect of individual mutations and the importance of their location in the ALP structure.

Open knee dislocation with a patellar tendon rupture: Result of staged surgical repair

Knee dislocation with concomitant multiligament injury is a rare and devastating injury. We report the successful repair of a rare case of open knee dislocation with concomitant multiligament injury and patellar tendon rupture of an 18-year-old male due to a motorcycle accident. The patient presented with an open wound running parallel to the knee joint line and patellar tendon rupture with full exposure of the cartilage of the distal femur. Staged surgical management including the application of a ring-type external fixator with a hinged joint, lateral collateral ligament repair, medial collateral ligament reconstruction using autogenous hamstring tendon, and joint release was performed. Range of movement was recovered to 0 degrees of knee extension and 80 degrees of knee flexion, and extension lag was negative. The Lysholm score of the patient was recovered to 92. The patient was able to return to work in the construction field 2 years after sustaining the injury. The patient had no complaint of pain and was able to resume construction work, even though reconstruction of the anterior cruciate ligament and posterior cruciate ligament was not performed. The application of a hinged ring-type external fixation device might play a key role in early range of movement restoration and to maintain the reduced position and acceptable recovery of the posterior cruciate ligament injury without the need for reconstructive surgery. This report is the first to describe the safety and effectiveness of staged surgical management for the repair of open knee dislocation with concomitant multiligament injury and patellar tendon rupture. However, further studies with longer follow-up periods will be needed to observe the development of osteoarthritis or weakness of the knee. Staged surgical management is a safe and effective procedure for repairing an open knee dislocation with concomitant multiligament injury and patellar tendon rupture.