Efficacy of radial styloid targeting screws in volar plate fixation of intra-articular distal radial fractures: a biomechanical study in a cadaver fracture model

<p>Abstract</p> <p>Background</p> <p>The locking screws target the radial styloid, theoretically provide greater stability against radial styloid fragment. However, it is unknown whether the radial styloid locking screws increased the stability of the volar plating system fixation along the entire distal radius or not. In this study, we evaluated the stability of the volar plating system fixation with or without the radial styloid screws using a biomechanical study in a cadaver fracture model.</p> <p>Methods</p> <p>Six matched pairs of fresh-frozen human cadaver wrists complete from the proximal forearm to the metacarpal bones were prepared to simulate standardized 3-part intra-articular and severe comminuted fractures. Specimens were fixed using the volar plating system with or without 2 radial styloid screws. Each specimen was loaded at a constant rate of 20 mm/min to failure. Load data was recorded and, ultimate strength and change in gap between distal and proximal fragments were measured. Data for ultimate strength and screw failure after failure loading were compared between the 2 groups.</p> <p>Results</p> <p>The average ultimate strength at failure of the volar plate fixation with radial styloid screws (913.5 ± 157.1 N) was significantly higher than that without them (682.2 ± 118.6 N). After failure loading, the average change in gap between the ulnar and proximal fragment was greater than that between the radial and proximal fragment. The number of bent or broken screws in ulnar fragment was higher than that in radial fragment. The number of specimens with bent or broken screws in cases with radial styloid screws was fewer than that in the fixation without radial styloid screws group.</p> <p>Conclusion</p> <p>The ulnar fragment is more intensively stressed than the radial fragment under axial loading of distal radius at full wrist extension. The radial styloid screws were effective in stable volar plate fixation of distal radial fractures.</p

Subclinical hypothyroidism and hypertension in relation to thyroid cysts: A cross-sectional study

Subclinical hypothyroidism is a condition characterized by a normal range of thyroid hormone [triiodothyronine (T 3) and thyroxine (T 4)] but with an elevated level of thyroid stimulating hormone (TSH) . It is also reported to be associated with hypertension. Since thyroid cysts could have a beneficial effect on the activation of thyroid hormone as reported in our previous study, their presence could influence the association between subclinical hypothyroidism and hypertension. To clarify those associations, a cross-sectional study of 1,724 Japanese within normal range of thyroid hormone (i.e., normal range of free T 3 and free T 4), aged 40-74 years, who participated in an annual health checkup in 2014 was conducted. Among the study population, 98 were diagnosed as having sublicnical hypothyroidism. For participants without a thyroid cyst, hypertension had a significant positive association with subclinical hypothyroidism, while for participants with a thyroid cyst, even though the power could not reach a significant value, an inverse tendency between hypertension and subclinical hypothyroidism was observed. The adjusted odd ratios (ORs) and 95% confidence intervals (CIs) were 1.91 (1.08, 3.37) for participants without thyroid cysts and 0.63 (0.26, 1.55) for participants with thyroid cysts, respectively. The status of thyroid cysts could act as a determining factor in the association between subclinical hypothyroidism and hypertension among participants within normal range of thyroid hormone

Phosphorylated Platelet-Derived Growth Factor Receptor-Positive Cells With Anti-apoptotic Properties Accumulate in the Synovium of Patients With Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease caused by inflammation of the synovium and characterized by chronic polyarthritis that destroys bone and cartilage. Fibroblast-like synoviocytes (FLSs) in the synovium of patients with RA can promote cartilage and bone destruction by producing proteins such as matrix metalloproteinases and receptor activator of NF-κB ligand, thereby representing an important therapeutic target for RA. FLSs have several phenotypes depending on which cell surface proteins and adhesion factors are expressed. Identifying the cellular functions associated with different phenotypes and methods of controlling them are considered essential for developing therapeutic strategies for RA. In this study, synovial tissue was collected from patients with RA and control subjects who required surgery due to ligament injury or fracture. Immunohistological analysis was used to investigate the rates of positivity for phosphorylated platelet-derived growth factor receptor-αβ (pPDGFRαβ) and cadherin-11 (CDH11) expression, and apoptosis-related markers were assessed for each cell phenotype. Next, FLSs were isolated in vitro and stimulated with tumor necrosis factor-α (TNF-α) in addition to a combination of PDGF and transforming growth factor (2GF) to investigate pPDGFRαβ and CDH11 expression and the effects of the inhibition of TNF and cyclin-dependent kinase (CDK) 4/6 on FLSs. Immunohistological analysis showed a large percentage of pPDGFRαβ+CDH11– cells in the sub-lining layer (SL) of patients with RA. These cells exhibited increased B-cell lymphoma-2 expression, reduced TNF receptor-1 expression, resistance to cell death, and abnormal proliferation, suggesting a tendency to accumulate in the synovium. Further, in vitro 2GF stimulation of FLSs lowered, whereas 2GF + TNF stimulation increased the pPDGFRαβ/CDH11 ratio. Hypothesizing that FLSs stimulated with 2GF + TNF would accumulate in vivo in RA, we determined the therapeutic effects of TNF and CDK4/6 inhibitors. The TNF inhibitor lowered the pPDGFRαβ/CDH11 ratio, whereas the CDK4/6 inhibitor suppressed cell proliferation. However, a synergistic effect was not observed by combining both the drugs. We observed an increase in pPDGFRαβ+CDH11– cells in the SL of the RA synovium and accumulation of these cells in the synovium. We found that the TNF inhibitor suppressed FLS activity and the CDK4/6 inhibitor reduced cell proliferation

Recognition of Connective Tissue Disease-Related Interstitial Pneumonia Based on Histological Score—A Validation Study of an Online Diagnostic Decision Support Tool

Objectives: to evaluate the number of cases of idiopathic pulmonary fibrosis (IPF) that included histological features of connective tissue disease (CTD) and to check whether they demonstrated the clinical features of CTD, using a previously reported CTD-interstitial pneumonia (IP) index that histologically differentiates CTD-associated and idiopathic IP. Methods: patients diagnosed with IPF following video-assisted thoracoscopic biopsy through multidisciplinary team diagnosis between 2014 and 2017 were selected. Pathological observation was made by four pathologists who scored eight observational items needed for the CTD-IP index. Cases determined as CTD, by the CTD-IP index, were extracted, and their clinical features were compared. Results: a total of 94 cases of IPF were identified, of which 20 were classified into the CTD group using the CTD-IP index with reasonable interobserver agreement (k = 0.76). Cases pathologically classified into the CTD group were significantly associated with female sex, non-smoking history, autoantibody positivity, and CTD symptoms (p = 0.01, 0.03, 0.01, and 0.04, respectively). Conclusions: patients with IPF with pathological findings of CTD showed clinical characteristics similar to those of patients with CTD

Ischemic Stroke in Acute Decompensated Heart Failure: From the KCHF Registry

[Background] Heart failure (HF) is a known risk factor for ischemic stroke, but data regarding ischemic stroke during hospitalization for acute decompensated HF (ADHF) are limited. [Methods and Results] We analyzed the data from a multicenter registry (Kyoto Congestive Heart Failure [KCHF] Registry) that enrolled 4056 consecutive patients with ADHF in Japan (mean age, 78 years; men, 2238 patients [55%]; acute coronary syndrome [ACS], 239 patients [5.9%]). We investigated the incidence and predictors of ischemic stroke during hospitalization for ADHF. During the hospitalization, 63 patients (1.6%) developed ischemic stroke. The median interval from admission to the onset of ischemic stroke was 7 [interquartile range: 2–14] days, and the most common underlying cause was cardioembolism (64%). Men (OR, 1.87; 95%CI, 1.11–3.24), ACS (OR, 2.31; 95%CI, 1.01–4.93), absence of prior HF hospitalization (OR, 2.21; 95%CI, 1.24–4.21), and high B‐type natriuretic peptide (BNP)/N‐terminal proBNP (NT‐proBNP) levels (above the median) at admission (OR, 3.15; 95%CI, 1.84–5.60) were independently associated with ischemic stroke. In patients without ACS, the independent risk factors for ischemic stroke were fully consistent with those in the main analysis. Higher quartiles of BNP/NT‐proBNP levels were significantly associated with higher incidence of ischemic stroke (P for trend, <0.001). Patients with ischemic stroke showed higher in‐hospital mortality, longer length of hospital stay, and poorer functional status at discharge. [Conclusions] During hospitalization for ADHF, 1.6% of the patients developed ischemic stroke. Men, ACS, absence of prior HF hospitalization, and high BNP/NT‐proBNP levels at admission were independently associated with ischemic stroke

Delineation of the mechanisms of tendon gliding resistance within the carpal tunnel

Background Forceful, high-velocity, and repetitive manual hand tasks contribute to the onset of carpal tunnel syndrome. This study aimed to isolate and identify mechanisms that contribute to tendon gliding resistance in the carpal tunnel. Methods Eight human cadaver hands (four pairs) were used. Tendon gliding resistance (force, energy, and stiffness) was measured under different conditions: with intact and with divided subsynovial connective tissue, at 2 mm/s and 60 mm/s tendon excursion velocity, and with and without relaxation time before tendon excursion. Results Subsynovial connective tissue stretching substantially contributed to increased gliding resistance force and energy during higher tendon excursion velocities, and subsynovial connective tissue stiffening was observed. Poroelastic properties of the tendon (and possibly the subsynovial connective tissue) also appear to be involved because relaxation time significantly increased gliding resistance force and energy (P < 0.01), and the difference in energy and force between high- and low-velocity tendon excursions increased with relaxation time (P = 0.01 and P < 0.01). Lastly, without relaxation time, no difference in force and energy was observed (P = 0.06 and P = 0.60), suggesting contact friction. Interpretation These findings are consistent with the hypothesis that the mechanics of tendon motion within the carpal tunnel are affected by the integrity of the subsynovial connective tissue. While not tested here, in carpal tunnel syndrome this tissue is known to be the fibrotic, thickened, and less-fluid-permeable. An extrapolation of our findings suggests that these changes in the subsynovial connective tissue of carpal tunnel syndrome patients could increase contact friction and carpal tunnel pressure

Effect of the 2020 hypersensitivity pneumonitis guideline on the pathologic diagnosis of interstitial pneumonia

Abstract It was reported that the 2020 guideline for hypersensitivity pneumonitis (HP) might result in the overdiagnosis of fibrotic HP (fHP). fHP and other types of interstitial pneumonias have several overlapping characteristics, and a high diagnostic concordance rate of fHP is rarely obtained. Therefore, we investigated the impact of the 2020 HP guideline on the pathological diagnosis of cases previously diagnosed as interstitial pneumonia. We identified 289 fibrotic interstitial pneumonia cases from 2014 to 2019 and classified them into four categories according to the 2020 HP guideline: typical, probable, and indeterminate for fHP and alternative diagnosis. The original pathological diagnosis of 217 cases were compared to their classification as either typical, probable, or indeterminate for fHP according to the 2020 guideline. The clinical data, including serum data and pulmonary function tests, were compared among the groups. Diagnoses changed from non-fHP to fHP for 54 (25%) of the 217 cases, of which, 8 were typical fHP and 46 were probable fHP. The ratio of typical and probable fHP cases to the total number of VATS cases was significantly lower when using transbronchial lung cryobiopsy (p < 0.001). The clinical data of these cases bore a more remarkable resemblance to those diagnosed as indeterminate for fHP than to those diagnosed as typical or probable. The pathological criteria in the new HP guidelines increase the diagnosis of fHP. However, it is unclear whether this increase leads to overdiagnosis, and requires further investigation. Transbronchial lung cryobiopsy may not be helpful when using the new criteria to impart findings for fHP diagnosis