The mortality of coronavirus disease 2019 (COVID-19) is strongly correlated with pulmonary vascular pathology accompanied by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection–triggered immune dysregulation and aberrant activation of platelets. We combined histological analyses using field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy analyses of the lungs from autopsy samples and single-cell RNA sequencing of peripheral blood mononuclear cells to investigate the pathogenesis of vasculitis and immunothrombosis in COVID-19. We found that SARS-CoV-2 accumulated in the pulmonary vessels, causing exudative vasculitis accompanied by the emergence of thrombospondin-1–expressing noncanonical monocytes and the formation of myosin light chain 9 (Myl9)–containing microthrombi in the lung of COVID-19 patients with fatal disease. The amount of plasma Myl9 in COVID-19 was correlated with the clinical severity, and measuring plasma Myl9 together with other markers allowed us to predict the severity of the disease more accurately. This study provides detailed insight into the pathogenesis of vasculitis and immunothrombosis, which may lead to optimal medical treatment for COVID-19.

Objective: The aim of this study was to determine whether advanced glycation end-products (AGEs) measured by skin autofluorescence (SAF) can serve as a biomarker for chronic low back pain. 111 patients who visited the outpatient clinic were included in this prospective cohort study. They were divided into a chronic low back pain group (C group: 48 patients, mean age 52.2) and a group without low back pain (N group: 63 healthy volunteers, mean age 40.8). SAF was measured as a parameter of AGEs using an autofluorescence reader. Measurements of low back pain visual analog scale (VAS), presence of diabetes, and SAF were recorded, and correlations between VAS or diabetes and SAF were investigated. Results: The C group had significantly higher SAF (2.20 vs 1.97, p<0.05) than the N group, whereas the SAF for diabetes patients was significantly higher (2.7 vs 2.1, p<0.05) than subjects without diabetes. SAF had no correlation with VAS (P=0.18). SAF is an indicator of AGE accumulation correlated with chronic low back pain and diabetes.

Background: Flexor tendon rupture is a major complication after volar locking plating for distal radius fracture (DRF). Few studies have investigated changes in the rate of postoperative flexor tendon rupture in patients with DRFs. The present study aimed to investigate the changes in the rate of postoperative flexor tendon rupture and to assess plate placement and reduction positions. Methods: We retrospectively reviewed patients in whom more than 24 months had passed since DRF surgery. The patients were interviewed by telephone. Forty-nine patients (50 fractures; 2007–2009) from institution A were included in group 1 and 81 patients (84 fractures; 2013–2016) from institution B were included in group 2. The DRF surgery method was similar between the two groups. The rate of flexor tendon rupture, Soong classification grade, and radiological index (i.e., volar tilt [VT], radial inclination [RI], and ulnar variance [UV]) were statistically investigated in both groups. Results: Patient epidemiology was not significantly different between the two groups. The flexor tendon rupture rates were 2% and 0% in groups 1 and 2, respectively, without a significant difference. With regard to the Soong grade, 44 fractures were grade 2 and 6 were grade 1 in group 1, whereas 18 were grade 2, 38 were grade 1, and 28 were grade 0 in group 2, with a significant difference (p < 0.05). With regard to the radiological index, the mean VT values were 5° and 11° in groups 1 and 2, respectively, with a significant difference (p < 0.05). However, RI and UV showed no significant difference. Conclusions: Plate placement and reduction positions, which are risk factors for flexor tendon ruptures after DRFs, have improved recently when compared with previous findings. With these changes, the rate of flexor tendon rupture is presumed to have decreased.

We encountered two cases of cervical disc herniation, wherein cerebrospinal fluid collection in the ventral epidural space between the cervical spine and the thoracic spine was noted. The patients, two women aged 71 and 43 years, were diagnosed with cervical disc herniation and underwent anterior cervical discectomy and fusion. Unexpected cerebrospinal fluid leakage was observed prior to exposure of the dura mater. Notably, the dura mater was intact following the removal of the herniated disc in both cases. No cerebrospinal fluid leakage symptoms were observed, and relief from the neurological symptoms related to the cervical disc herniation was observed in both cases following the surgery. Findings of preoperative magnetic resonance imaging and computed tomography myelography were carefully reviewed, retrospectively. Both patients presented with similar features including expansion of cerebrospinal fluid collection in the ventral epidural space between the cervical spine and the thoracic spine. These observed features were similar to those of superficial siderosis, which is a form of duropathy—a disease caused by dural defects. Therefore, the patients in this case study might have a subclinical duropathy with associated cervical disc herniation.