Custom nasal obturator for velopharyngeal dysfunction: Digitizing the fabrication process.

Nasal obturation using a removable medical device is a suitable treatment option for patients with velopharyngeal dysfunction. In the United Kingdom in recent years, the use of nasal obturation has increased because of the successful collaborations among the Speech and Language Therapy, Restorative Dentistry, and Maxillofacial departments. However, fabrication of the devices requires specialist skill and considerable time. A digital process which facilitates the rapid, cost effective production of a light, comfortable, unobtrusive nasal obturator is described.

Virtual planning for corrections of hemifacial microsomia.

Objectives: This article describes the many anomalies within and outside the head and neck of hemifacial microsomia (HFM). Methods: The OMENS+ classification system is described with particular reference to the mandibular features classified by Pruzansky and modified by Kaban. The application of virtual surgical planning (VSP) to HFM, largely in children, is described and taken through to aspects indicated in maturity. Results: VSP is demonstrated with clinical cases examples in HFM patients for (1) grafts and flaps replacing missing parts of the zygomatic bone, temporo-mandibular joint and mandible, (2) distraction osteogenesis for lengthening of the mandibular ramus, advancement of the mandibular body, widening of the face and simultaneous mid-face and mandibular rotation, (3) implants and correction of microtia for bone anchored ear prostheses, (4) correction of microtia by autogenous ear construction, and (5) end stage rotational bimaxillary osteotomies. Conclusions: 3D virtual and physical planning is a valuable adjunct to the treatment of this complex condition.

AtomAccess: A Predictive Tool for Molecular Design and Its Application to the Targeted Synthesis of Dysprosium Single-Molecule Magnets.

Isolated dysprosocenium cations, [Dy(CpR)2]+ (CpR = substituted cyclopentadienyl), have recently been shown to exhibit superior single-molecule magnet (SMM) properties over closely related complexes with equatorially bound ligands. However, gauging the crossover point at which the CpR substituents are large enough to prevent equatorial ligand binding, but small enough to approach the metal closely and generate strong crystal field splitting has required laborious synthetic optimization. We therefore created the computer program AtomAccess to predict the accessibility of a metal binding site and its ability to accommodate additional ligands. Here, we apply AtomAccess to identify the crossover point for equatorial coordination in [Dy(CpR)2]+ cations in silico and hence predict a cation that is at the cusp of stability without equatorial interactions, viz., [Dy(Cpttt)(Cp*)]+ (Cpttt = C5H2tBu3-1,2,4, Cp* = C5Me5). Upon synthesizing this cation, we found that it crystallizes as either a contact ion-pair, [Dy(Cpttt)(Cp*){Al[OC(CF3)3]4-κ-F}], or separated ion-pair polymorph, [Dy(Cpttt)(Cp*)][Al{OC(CF3)3}4]·C6H6. Upon characterizing these complexes, together with their precursors, yttrium and yttrium-doped analogues, we find that the contact ion-pair shows inferior SMM properties to the separated ion-pair, as expected, due to faster Raman and quantum tunneling of magnetization relaxation processes, while the Orbach region is relatively unaffected. The experimental verification of the predicted crossover point for equatorial coordination in this work tests the limitations of the use of AtomAccess as a predictive tool and also indicates that the application of this type of program shows considerable potential to boost efficiency in exploratory synthetic chemistry.

Risk of Mortality Related to Recurrent Limb Events After Endovascular Revascularization of the Superficial Femoral Artery for Peripheral Artery Disease: The Boston Femoral Artery Endovascular Revascularization Outcomes (Boston FAROUT) Study.

Endovascular revascularization of the superficial femoral artery (SFA) may lead to recurrent ischemic syndromes, revascularization, or amputation. The impact of these events on mortality is unknown. We followed all patients having SFA endovascular revascularization for claudication or chronic limb-threatening ischemia in 2 cardiovascular (CV) divisions in Boston, Massachusetts. Any recurrent limb event after the initial SFA revascularization included recurrent claudication (67%), limb ulceration or gangrene (13%), repeat endovascular revascularization (61%), surgical revascularization (15%), or major (9%) or minor amputation (8%). We linked data to the National Death Index to ascertain cause of death grouped into CV mortality, or non-CV mortality. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) from Cox proportional hazards and sub-HRs from Fine-Gray competing risks analyses were clustered by patient. Overall, there were 202 patients with 253 index limb endovascular procedures. A recurrent limb event occurred in 123 limbs (49%) and 93 patients (46%). Patients with and without recurrent limb events had similar numbers of deaths over follow-up (76 [62%] vs 71 [55%], respectively). In multivariable models, recurrent limb event was not related to all-cause death (HR 0.92, 95% CI 0.64 to 1.33), CV death (HR 1.29, 95% CI 0.72 to 1.30), or non-CV death (HR 0.65, CI 0.39 to 1.07). Competing risk analyses suggested male gender and chronic limb-threatening ischemia were more strongly related to CV death, and chronic kidney more strongly related to disease to non-CV death. In conclusion, recurrent limb events, which contribute to patient morbidity, do not increase the risk of all-cause or cause-specific mortality, and should not discourage repeat revascularization to relieve symptoms or ischemia.

Physical Grounds for Causal Perspectivalism.

We ground the asymmetry of causal relations in the internal physical states of a special kind of open and irreversible physical system, a causal agent. A causal agent is an autonomous physical system, maintained in a steady state, far from thermal equilibrium, with special subsystems: sensors, actuators, and learning machines. Using feedback, the learning machine, driven purely by thermodynamic constraints, changes its internal states to learn probabilistic functional relations inherent in correlations between sensor and actuator records. We argue that these functional relations just are causal relations learned by the agent, and so such causal relations are simply relations between the internal physical states of a causal agent. We show that learning is driven by a thermodynamic principle: the error rate is minimised when the dissipated power is minimised. While the internal states of a causal agent are necessarily stochastic, the learned causal relations are shared by all machines with the same hardware embedded in the same environment. We argue that this dependence of causal relations on such 'hardware' is a novel demonstration of causal perspectivalism.

Characterisation of magnetic relaxation on extremely long timescales.

The use of magnetisation decay measurements to characterise very slow relaxation of the magnetisation in single-molecule magnets is becoming increasingly prevalent as relaxation times move to longer timescales outside of the AC susceptibility range. However, experimental limitations and a poor understanding of the distribution underlying the stretched exponential function, commonly used to model the data, may be leading to misinterpretation of the results. Herein we develop guidelines on the experimental design, data fitting, and analysis required to accurately interpret magnetisation decay measurements. Various measures of the magnetic relaxation rate extracted from magnetisation decay measurements of [Dy(Dtp)2][Al{OC(CF3)3}4] previously characterised by Evans et al., fitted using combinations of fixing or freely fitting different parameters, are compared to those obtained using the innovative square-wave "waveform" technique of Hilgar et al. The waveform technique is comparable to AC susceptometry for measurement of relaxation rates on long timescales. The most reliable measure of the relaxation time for magnetisation decays is found to be the average logarithmic relaxation time, e〈ln[τ]〉, obtained via a fit of the decay trace using a stretched exponential function, where the initial and equilibrium magnetisation are fixed to first measured point and target values respectively. This new definition causes the largest differences to traditional approaches in the presence of large distributions or relaxation rates, with differences up to 50% with ß = 0.45, and hence could have a significant impact on the chemical interpretation of magnetic relaxation rates. A necessary step in progressing towards chemical control of magnetic relaxation is the accurate determination of relaxation times, and such large variations in experimental measures stress the need for consistency in fitting and interpretation of magnetisation decays.

Transverse colon volvulus and the wandering liver.

INTRODUCTION AND IMPORTANCE: Transverse colon volvulus is a rare cause of colonic obstruction accounting for 1-3 % of colonic volvuli due to the short mesentery and hepatic and splenic attachments. Previous mobilisation of the flexures and conditions resulting in chronic dilatation of the colon predispose to the condition. The risk of mortality is high, ranging from 11 to 20 % highlighting the need for early diagnosis and intervention. CASE PRESENTATION: We present a case of a 90-year-old male who was referred with a large bowel obstruction with a transition at the splenic flexure and the liver rotated to the left upper quadrant. The patient was taken to the theatre and an emergency laparotomy was performed with findings of a transverse colon volvulus. The liver was initially found in the left upper quadrant and was freely mobile in the upper abdomen consistent with an absence of the hepatic ligament. A subtotal colectomy was performed. Unfortunately, the postoperative course was complicated by a cardiac event and the patient died on postoperative day six. CLINICAL DISCUSSION: Absence of hepatic ligaments is a rare cause of transverse colon volvulus which has only been described in one previous case report. Diagnosis of transverse colon volvulus can be challenging and early operative intervention with colectomy is required to minimise mortality. CONCLUSION: This case illustrates an unusual cause of transverse colon volvulus secondary to the absence of the hepatic ligaments and stresses the need for early diagnosis and intervention due to the high mortality associated with this condition.

Influence of pressure on a dysprosocenium single-molecule magnet.

The effects of external pressure on a high-performing dysprosocenium single-molecule magnet are investigated using a combination of X-ray diffraction, magnetometry and theoretical calculations. The effective energy barrier (Ueff) decreases from ca. 1300 cm-1 at ambient pressure to ca. 1125 cm-1 at 3 GPa. Our results indicate that compression < 1.2 GPa has a negligible effect on the Orbach process, but magnetic relaxation > 1 GPa increases via Raman relaxation and/or quantum tunnelling of magnetisation.

3D Printing Technology for Chest Wall Reconstruction With a Sternum-Ribs-Cartilage Titanium Implant: From Ideation to Creation.

OBJECTIVE: We describe the use of 3-dimensional (3D) printing technology to plan and reconstruct the sternum, adjoining cartilages, and ribs with a custom-made, anatomically designed, 3D-printed titanium implant for an isolated sternal metastasis complicated with a pathological fracture. METHODS: We imported submillimeter slice computed tomography scan data into Mimics Medical 20.0 software and by manual bone threshold segmentation created a 3D virtual model of the patient's chest wall and tumor. For all-around tumor-free margins, we grew the tumor by 2 cm. The replacement implant was designed in 3D using the anatomical features of the sternum, cartilages, and ribs and manufactured using TiMG 1 powder fusion technology. Physiotherapy was provided prior to and following surgery, and the impact of reconstruction on pulmonary functions was assessed. RESULTS: At surgery, the precise resection, clear margins, and a secure fit were achieved. At follow-up, there was no dislocation, paradoxical movement, change in performance status, or dyspnea. There was a decrease in forced expiratory volume in 1 s (FEV1) from 105% prior to surgery to 82% following surgery and in forced vital capacity (FVC) from 108% to 75%, with no difference in the FEV1/FVC ratio, suggesting a restrictive pattern of impairment. CONCLUSIONS: With 3D printing technology, reconstructing a large anterior chest wall defect with a custom-made, anatomical, 3D-printed titanium alloy implant is feasible and safe, and it preserves the shape, structure, and function of the chest wall, albeit with a restrictive pattern of pulmonary function, which can be addressed with physiotherapy.

Measurement of the Quantum Tunneling Gap in a Dysprosocenium Single-Molecule Magnet.

We perform magnetization sweeps on the high-performing single-molecule magnet [Dy(Cpttt)2][B(C6F5)4] (Cpttt = C5H2tBu3-1,2,4; tBu = C(CH3)3) to determine the quantum tunneling gap of the ground-state avoided crossing at zero-field, finding a value on the order of 10-7 cm-1. In addition to the pure crystalline material, we also measure the tunnel splitting of [Dy(Cpttt)2][B(C6F5)4] dissolved in dichloromethane (DCM) and 1,2-difluorobenzene (DFB). We find that concentrations of 200 or 100 mM [Dy(Cpttt)2][B(C6F5)4] in these solvents increases the size of the tunneling gap compared to the pure sample, despite a similarity in the strength of the dipolar fields, indicating that either a structural or vibrational change due to the environment increases quantum tunneling rates.

A Systematic Review and Meta-Analysis of Nerve Gap Repair: Comparative Effectiveness of Allografts, Autografts, and Conduits.

BACKGROUND: Ideal nerve repair involves tensionless direct repair, which may not be possible after resection. Bridging materials include nerve autograft, allograft, or conduit. This study aimed to perform a systematic literature review and meta-analysis to compare the meaningful recovery (MR) rates and postoperative complications following autograft, allograft, and conduit repairs in nerve gaps greater than 5 mm and less than 70 mm. A secondary aim was to perform a comparison of procedure costs. METHODS: The search was conducted in MEDLINE from January of 1980 to March of 2020, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were included whether they reported nerve injury type, repair type, gap length, and outcomes for MR rates. Thirty-five studies with 1559 nerve repairs were identified. RESULTS: Overall MR for sensory and motor function was not significantly different between autograft ( n = 670) and allograft ( n = 711) across both short and long gaps. However, MR rates for autograft (81.6%) and allograft (87.1%) repairs were significantly higher compared with conduits (62.2%) ( P < 0.05) in sensory short gap repairs. Complication rates were comparable for autograft and allograft but higher for conduit with regard to pain. Analysis of costs showed that total costs for allograft repair were less than autograft in the inpatient setting and were comparable in the outpatient setting. CONCLUSIONS: Literature showed comparable rates of MR between autograft and allograft, regardless of gap length or nerve type. Furthermore, the rates of MR were lower in conduit repairs. In addition, the economic analysis performed demonstrates that allograft does not represent an increased economic burden compared with autograft.

Validation of a Smartphone-Based Institutional Electronic Data Capture System for Thumb Carpometacarpal Joint Arthroplasty.

BACKGROUND: The Orthopaedic Minimal Data Set (OrthoMiDaS) Episode of care (OME) is a prospectively collected database enabling capture of patient and surgeon-reported data in a more efficient, comprehensive, and dependable manner than electronic medical record (EMR) review. We aimed to assess and validate the OME as a data capture tool for carpometacarpal (CMC) arthroplasty compared to traditional EMR-based review. Specifically, we aimed to: (1) compare the completeness of the OME versus EMR data; and (2) evaluate the extent of agreement between the OME and EMR data-based datasets for carpometacarpal (CMC) arthroplasty. METHODS: The first 100 thumb CMC arthroplasties after OME inception (Febuary, 2015) were included. Blinded EMR-based review of the same cases was performedfor 48 perioperative variables and compared to their OME-sourced counterparts. Outcomes included completion rates and agreement measures in OME versus EMR-based control datasets. RESULTS: The OME demonstrated superior completion rates compared to EMR-based retrospective review. There was high agreement between both datasets where 75.6% (34/45) had an agreement proportion of >0.90% and 82.2% (37/45) had an agreement proportion of >0.80. Over 40% of the variables had almost perfect to substantial agreement (κ > 0.60). Among the 6 variables demonstrating poor agreement, the surgeon-inputted OME values were more accurate than the EMR-based review control. CONCLUSIONS: This study validates the use of the OME for CMC arthroplasty by illustrating that it is reliably able to match or supersede traditional chart review for data collection; thereby offering a high-quality tool for future CMC arthroplasty studies.

A preliminary study of radioulnar wrist compression in improving patient-reported outcomes of carpal tunnel syndrome.

Previous studies have shown radioulnar wrist compression augments carpal arch space. This study investigated the effects of radioulnar wrist compression on patient-reported outcomes associated with carpal tunnel syndrome. Subjects underwent thrice-daily (15 min each time 45 min daily) wrist compression over 4 weeks with an additional four weeks of follow-up without treatment. Primary outcomes included Boston Carpal Tunnel Questionnaire symptom and functional severity scales (SSS and FSS) and symptoms of numbness/tingling based on Visual Analog Scales. Our results showed that radioulnar wrist compression improved SSS by 0.55 points after 2 weeks (p < 0.001) and 0.51 points at 4 weeks (p < 0.006) compared to the baseline scale. At the four-week follow-up, SSS remined improved at 0.47 points (p < 0.05). Symptoms of numbness/tingling improved at two and 4 weeks, as well as the follow-up (p < 0.05). Hand motor impairment such as weakness had a lower frequency across carpal tunnel syndrome sufferers and does not significantly improve (p > 0.05). Radioulnar wrist compression might be an effective alternative treatment in improving sensory related symptoms in patients with mild to moderate carpal tunnel syndrome.

Opposing effects of spatiotemporal variation in resources and temporal variation in climate on density dependent population growth in seabirds.

Understanding how ecological processes combine to shape population dynamics is crucial in a rapidly changing world. Evidence has been emerging for how fundamental drivers of density dependence in mobile species are related to two differing types of environmental variation-temporal variation in climate, and spatiotemporal variation in food resources. However, to date, tests of these hypotheses have been largely restricted to mid-trophic species in terrestrial environments and thus their general applicability remains unknown. We tested if these same processes can be identified in marine upper trophic level species. We assembled a multi-decadal data set on population abundance of 10 species of colonial seabirds comprising a large component of the UK breeding seabird biomass, and covering diverse phylogenies, life histories and foraging behaviours. We tested for evidence of density dependence in population growth rates using discrete time state-space population models fit to long time-series of observations of abundance at seabird breeding colonies. We then assessed if the strength of density dependence in population growth rates was exacerbated by temporal variation in climate (sea temperature and swell height), and attenuated by spatiotemporal variation in prey resources (productivity and tidal fronts). The majority of species showed patterns consistent with temporal variation in climate acting to strengthen density dependent feedbacks to population growth. However, fewer species showed evidence for a weakening of density dependence with increasing spatiotemporal variation in prey resources. Our findings extend this emerging theory for how different sources of environmental variation may shape the dynamics and regulation of animal populations, demonstrating its role in upper trophic marine species. We show that environmental variation leaves a signal in long-term population dynamics of seabirds with potentially important consequences for their demography and trophic interactions.

Spontaneous Decomposition of an Extraordinarily Twisted and Trans-Bent Fully-Phosphanyl-Substituted Digermene to an Unusual GeI Cluster.

Ditetrelenes R2 E=ER2 (E=Si, Ge, Sn, Pb) substituted by multiple N/P/O/S-donor groups are extremely rare due to their propensity to disaggregate into their tetrylene monomers R2 E. We report the synthesis of the first fully phosphanyl-substituted digermene {(Mes)2 P}2 Ge=Ge{P(Mes)2 }2 (3, Mes=2,4,6-Me3 C6 H2 ), which adopts a highly unusual structure in the solid state, that is both strongly trans-bent and highly twisted. Variable-temperature 31 P{1 H} NMR spectroscopy suggests that 3 persists in solution, but is subject to a dynamic equilibrium between two conformations, which have different geometries about the Ge=Ge bond (twisted/non-twisted) due to a difference in the nature of their π-stacking interactions. Compound 3 undergoes unprecedented, spontaneous decomposition in solution to give a unique GeI cluster {(Mes)2 P}4 Ge4 ⋅5 CyMe (7).

Shipping in the north-east Atlantic: Identifying spatial and temporal patterns of change.

Maritime traffic is increasing globally, with a four-fold increase in commercial vessel movements between 1992 and 2012. Vessels contribute to noise and air pollution, provide pathways for non-native species, and collide with marine wildlife. While knowledge of shipping trends and potential environmental impacts exists at both local and global levels, key information on vessel density for regional-scale management is lacking. This study presents the first in-depth spatio-temporal analysis of shipping in the north-east Atlantic region, over three years in a five-year period. Densities increased by 34%, including in 73% of Marine Protected Areas. Western Scotland and the Bay of Biscay experienced the largest increases in vessel density, predominantly from small and slow vessels. Given well-documented impacts that shipping can have on the marine environment, it is crucial that this situation continues to be monitored - particularly in areas designated to protect vulnerable species and ecosystems which may already be under pressure.

Triceps tongue versus olecranon osteotomy for intra-articular distal humeral fractures: a matched-cohort study.

BACKGROUND: There are various approaches to the distal humerus when managing a distal humeral fracture, and controversy exists regarding which approach is optimal. The purpose of this study was to report the outcomes of the triceps tongue (TT) approach when used for osteosynthesis of AO type 13-A, B, and C distal humeral fractures. Secondarily, we aimed to compare the outcomes of the TT approach vs. olecranon osteotomy (OO) when used for osteosynthesis of AO type 13-C distal humeral fractures. METHODS: We performed a retrospective review of patients with distal humeral fractures treated with open reduction-internal fixation by either a TT or OO approach between 2007 and 2019 at 2 separate institutions. TT patients with AO type 13-C fractures were matched to OO patients at a 1:1 ratio based on age, sex, and fracture characteristics. Surgical time, intraoperative blood loss, elbow motion, fracture union, complications, and Disabilities of the Arm, Shoulder and Hand scores were compared. RESULTS: A total of 28 patients treated with the TT approach were assessed, and the matched TT and OO cohorts each comprised 15 patients. The TT group showed less blood loss (119.3 mL vs. 268.5 mL, P = .03), had greater maximal flexion (126° vs. 116°, P = .03), and achieved a larger flexion-extension arc (108° vs. 93°, P = .05) than the OO group. In the OO cohort, 27% of patients had complications directly related to the OO, and OO patients had a higher rate of postoperative ulnar nerve neuritis (33% vs. 0%, P = .04). There was no difference in Disabilities of the Arm, Shoulder and Hand score (P = .08), procedure time (P = .2), total number of patients with ≥1 complication (P = .5), difficulty with union (P = .7), or number of patients requiring revision surgery (P = .7). CONCLUSIONS: The TT approach is a safe and effective approach for the treatment of distal humeral fractures. When compared with the OO approach for AO type 13-C fractures, the TT approach did not differ regarding functional outcomes but showed increased range of motion, decreased intraoperative blood loss, and a lower rate of postoperative ulnar nerve neuritis. The TT approach should be considered as a safe and reliable first-line approach for intra-articular distal humeral fractures because it allows adequate visualization of the articular surface, eliminates complications related to osteotomy including delayed union or nonunion and hardware failure or irritation, and allows for easy conversion to total elbow arthroplasty.

Combined Treatment of Trapeziometacarpal Joint Arthritis and Scapholunate Advanced Collapse Wrist.

PURPOSE: The combined treatment of trapeziometacarpal joint arthritis and scapholunate advanced collapse (SLAC) wrist presents unique challenges. The consequences of the loss of radial column support caused by scaphoidectomy and trapeziectomy are not well known. The purpose of this study was to evaluate the outcomes of the simultaneous and staged treatment of trapeziometacarpal joint arthritis and SLAC wrist. METHODS: A retrospective review of patients who underwent surgery for both trapeziometacarpal joint arthritis and SLAC wrist was performed. The wrist and thumb range of motion; grip and pinch strength; pain; quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores; and radiographs were analyzed. RESULTS: Twenty-four patients who underwent both trapeziectomy and 1 of 3 procedures for SLAC wrist (4-corner fusion [n = 10]), proximal row carpectomy [n = 9], and total wrist arthroplasty [n = 5]) in a single stage (n = 10) or in 2 stages (n = 14) were included. The median age was 63 years. The median follow-up period was 35 months. Twelve (50%) patients underwent complete scaphoidectomy, and 12 (50%) patients underwent partial scaphoidectomy. All 3 procedures resulted in an improvement in pain at rest, pain during activity, and quick Disabilities of the Arm, Shoulder and Hand scores. The final range of motion, grip and pinch strength, and complication rates were consistent with those reported in the literature for isolated procedures. CONCLUSIONS: Trapeziometacarpal joint arthritis and SLAC wrist may be treated either simultaneously or in stages. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.