Delayed Extension Block Pinning in 27 Patients With Mallet Fracture

Background: Untreated bony mallet fingers can cause an array of problems; therefore, adequate treatment is essential. The primary aim of this study was to determine the patient-reported functional outcome of delayed surgical intervention of bony mallet fingers. The secondary aim was to determine the complication rate of delayed surgical intervention. Methods: In this single-center retrospective cohort study, all consecutive patients treated between 2010 and 2016 at our level 2 regional teaching hospital were included. Inclusion criterion was a bony mallet finger injury (excluding the thumb), presenting >21 days after injury, treated with extension block pinning. Indications for surgery were >2 mm fragment displacement or volar subluxation of the distal interphalangeal joint. Six to 82 months postoperatively, patients completed the Patient-Rated Wrist and Hand Evaluation (PRWHE) by phone. Complications were extracted by chart review. Results: Twenty-seven patients were included, and all completed the PRWHE. Median time to surgery was 35 days (interquartile range [IQR] = 29-42; range = 22-61). Reasons for delay in surgical treatment were patient/physician delay in 24 cases and failed conservative treatment in 3 cases. The median PRWHE score was 0 (IQR = 0-5; range = 0-22.5). After retrospective assessment of the outpatient charts, no early symptoms of malunion or nonunion were found. One patient had a loss of Kirschner-wire fixation, which was corrected. Three patients had an infection that required antibiotic treatment. Conclusions: Delayed surgical management of bony mallet fingers demonstrated adequate functional outcome with minimal complications when compared with prior literature.     

Influence of Orientation and Radiative Heat Transfer on Aluminum Foams in Buoyancy-Induced Convection

Two differently-produced open-cell aluminum foams were compared to a commercially available finned heat sink. Further, an aluminum plate and block were tested as a reference. All heat sinks have the same base plate dimensions of four by six inches. The first foam was made by investment casting of a polyurethane preform and has a porosity of 0.946 and a pore density of 10 pores per linear inch. The second foam is manufactured by casting over a solvable core and has a porosity of 0.85 and a pore density of 2.5 pores per linear inch. The effects of orientation and radiative heat transfer are experimentally investigated. The heat sinks are tested in a vertical and horizontal orientation. The effect of radiative heat transfer is investigated by comparing a painted/anodized heat sink with an untreated one. The heat flux through the heat sink for a certain temperature difference between the environment and the heat sink’s base plate is used as the performance indicator. For temperature differences larger than 30 ^°C, the finned heat sink outperforms the in-house-made aluminum foam heat sink on average by 17%. Furthermore, the in-house-made aluminum foam dissipates on average 12% less heat than the other aluminum foam for a temperature difference larger than 40 ^°C. By painting/anodizing the heat sinks, the heat transfer rate increased on average by 10% to 50%. Finally, the thermal performance of the horizontal in-house-made aluminum foam heat sink is up to 18% larger than the one of the vertical aluminum foam heat sink.     

A randomized cross-over trial to define neurophysiological correlates of AV-101 N-methyl-d-aspartate receptor blockade in healthy veterans

The kynurenine pathway (KP) is a strategic metabolic system that combines regulation of neuronal excitability via glutamate receptor function and neuroinflammation via other KP metabolites. This pathway has great promise in treatment of depression and suicidality. The KP modulator AV-101 (4-chlorokynurenine, 4-Cl-KYN), an oral prodrug of 7-chlorokynurenic acid (7-Cl-KYNA), an N-methyl-d-aspartate receptor (NMDAR) glycine site antagonist, and of 4-chloro-3-hydroxyanthranilic acid (4-Cl-3-HAA), a suppressor of NMDAR agonist quinolinic acid (QUIN), is a promising potential antidepressant that targets glutamate functioning via the KP. However, a recent placebo-controlled clinical trial of AV-101 in depression found negative results. This raises the question of whether AV-101 can penetrate the brain and engage the NMDAR and KP effectively. To address this problem, ten healthy US military veterans (mean age = 32.6 years ± 6.11; 1 female) completed a phase-1 randomized, double-blind, placebo-controlled, crossover study to examine dose-related effects of AV-101 (720 and 1440 mg) on NMDAR engagement measured by γ-frequency band auditory steady-state response (40 Hz ASSR) and resting EEG. Linear mixed models revealed that 1440 mg AV-101, but not 720 mg, increased 40 Hz ASSR and 40 Hz ASSR γ-inter-trial phase coherence relative to placebo. AV-101 also increased 4-Cl-KYN, 7-Cl-KYNA, 4-Cl-3-HAA, 3-HAA, and KYNA in a dose-dependent manner, without affecting KYN and QUIN. AV-101 was safe and well tolerated. These results corroborate brain target engagement of 1440 mg AV-101 in humans, consistent with blockade of interneuronal NMDAR blockade. Future studies should test higher doses of AV-101 in depression. Suicidal behavior, which has been associated with high QUIN and low KYNA, is also a potential target for AV-101.Subject terms: Biomarkers, Neurophysiology, Neuroscience     

Prior use of anticoagulation is associated with a better survival in COVID-19

Journal of Thrombosis and Thrombolysis - Coronavirus disease 2019 (COVID-19) is associated with a high incidence of venous and arterial thromboembolic events. The role of anticoagulation (AC) prior...     

Inflammatory Rheumatic Disorders and Bone

Inflammatory joint diseases such as rheumatoid arthritis, as well as other rheumatic conditions, such as systemic lupus erythematosus (SLE) and ankylosing spondylitis, comprise a heterogeneous group of joint disorders that are all associated with extra-articular side effects, including bone loss and fractures. The concept of osteoimmunology is based on growing insights into the links between the immune system and bone. The pathogenesis of osteoporosis in these patients is multifactorial. We have, more or less as an example, described this extensively for patients with SLE. High disease activity (inflammation) and immobility are common factors that substantially increase fracture risk in these patients, on top of the background fracture risk based on, among other factors, age, body mass index, and gender. Although no fracture reduction has been shown in intervention studies in patients with inflammatory rheumatic diseases, we present treatment options that might be useful for clinicians who are treating these patients.