Persistent pain around the greater trochanter is a common complication after total hip arthroplasty. Restoration of biomechanics such as leg length, femoral und acetabular offset is crucial in THA. ...The purpose of this study was to evaluate postoperative differences of these parameters after THA and to analyze their association to greater trochanteric pain syndrome. Furthermore, we aimed to evaluate the clinical relevance of trochanteric pain syndrome compared to patient reported outcome measures. 3D-CT scans of 90 patients were analyzed after minimalinvasive total hip arthroplasty and leg length, femoral and acetabular offset differences were measured. Clinical evaluation was performed three years after THA regarding the presence of trochanteric pain syndrome and using outcome measures. Furthermore, the patients' expectation were evaluated. Patients with trochanteric pain syndrome showed a higher absolute discrepancy of combined leg length, femoral and acetabular offset restoration compared to the non-operated contralateral side with 11.8 ± 6.0 mm than patients without symptoms in the trochanteric region with 7.8 ± 5.3 mm (p = 0.01). Patients with an absolute deviation of the combined parameters of more than 5 mm complained more frequently about trochanteric symptoms (29.2%, 19/65) than patients with a biomechanical restoration within 5 mm compared to the non-affected contralateral side (8.0%, 2/25, p = 0.03). Clinical outcome measured three years after THA was significantly lower in patients with trochanteric symptoms than without trochanteric pain (p < 0.03). Similarly, fulfillment of patient expectations as measured by THR-Survey was lower in the patients with trochanteric pain (p < 0.005). An exact combined restoration of leg length, acetabular and femoral offset reduces significantly postoperative trochanteric pain syndrome and improves the clinical outcome of the patients.
Background
Iliopsoas tendon impingement is one possible reason for persistent groin pain and diminished functional outcome after THA. So far, estimation by eye and palpation is the standard procedure ...to intraoperatively assess the distance of the cup to the anterior rim. However, novel technologies such as imageless navigation enable intraoperative measurements of the cup in relation to the psoas tendon and bony landmarks.
Questions/purposes
We asked whether psoas impingement (1) can be reduced using imageless navigation compared with the standard technique and (2) is associated with specific patient characteristics. Furthermore, we investigated (3) if anterior cup protrusion (overhang) is associated with lower outcome scores for pain and function.
Methods
The current study is a reanalysis of data from a randomized controlled trial evaluating navigation for THA; 135 patients were randomized for surgery with or without the use of imageless navigation. The risk for anterior protrusion of the cup above the acetabular rim and thus potential psoas impingement, defined as an overhang of the cup above the anterior acetabular rim as measured on postoperative CT, was either controlled with the help of navigation or standard control by eye and palpation intraoperatively. Postoperatively, the anterior protrusion of the cup above the acetabular rim was measured on three-dimensional (3-D) CT by a blinded, external institute. In addition to patient-related outcome measures, the Harris hip score, Hip disability and Osteoarthritis Outcome Score, and EuroQol were obtained 1 year postoperatively. Altogether 123 data sets were available for primary analysis and 115 were available for 1-year followup.
Results
There was no difference, with the numbers available, between the navigated and the control groups in terms of the mean distance of the cup below the anterosuperior acetabular rim (3.9 mm; −5.3 to 12.6 mm versus 4.4 mm; −7.9 to 13.7 mm; p = 0.72) or the anteroinferior acetabular rim (4.7 mm; −6.2 to 14.8 mm versus 4.2 mm; −7.1 to 16.3 mm; p = 0.29). There was no difference, with the numbers available, in terms of the proportion of cups with anterior overhang (7%, four of 57 versus, 15%, 10 of 66; p = 0.16), respectively. After controlling for potential confounding variables such as cup inclination, cup size, patient age, BMI, stage of arthritis, and length of skin incision, we found cup anteversion (hazard ratio HR, 0.87; 95% CI, 0.81–0.93; p < 0.001) and female sex (HR, 3.88; 95% CI, 1.01–14.93; p = 0.049) were associated with a propensity to potential psoas impingement. With the numbers available, there were no differences observed in clinical scores between groups with and without anterior cup protrusion.
Conclusions
We found no differences between imageless navigation and estimation by eye and palpation in preventing potential psoas impingement. Despite the comparable clinical outcome for patients with and without cup protrusion, the orthopaedic surgeon should be especially aware of propensity for psoas impingement in women.
Level of Evidence
Level II, therapeutic study.
We evaluated the long-term morphologic and clinical outcomes after thoracic endovascular aortic repair combined with parallel grafts (PG-TEVAR) for arch-involving aortic pathologies.
We performed a ...retrospective analysis of perioperative and follow-up data of patients who had undergone PG-TEVAR at a single vascular surgery center from November 2010 to April 2018. Patients with prior or simultaneous open chest or cervical debranching procedures or arch repair were excluded. The primary endpoint was freedom from overall PG-TEVAR–related reintervention. The secondary endpoints were parallel graft sealing zone failure (presence of gutter-related type I or Ic endoleak), PG failure (occlusion or reintervention), stroke, and 30-day and overall PG-TEVAR–related and all-cause mortality. Kaplan-Meier curves were used to estimate the freedom from reintervention and survival. Receiver operating characteristics curves were used to find the optimal cutoff to prevent type Ia endoleak-related reintervention.
A total of 33 patients, including 8 women, with a median age of 74 years (interquartile range, 67-79 years) had undergone PG-TEVAR (chimney, periscope, and sandwich in 20, 15, and 13 patients, respectively) with proximal landing in Ishimaru zone 0, 1, or 2 in 4, 5, and 24 patients, respectively. The aortic pathologies included type B aortic dissection (acute and chronic, eight and six, respectively), degenerative aneurysm (n = 10), type Ia endoleak (n = 3), para-anastomotic/patch aneurysm (n = 4), left subclavian artery aneurysm (n = 1), and traumatic rupture (n = 1). The perioperative stroke rate and 30-day mortality was 6% and 9%, respectively. Direct postoperative computed tomography revealed 28 endoleaks (gutter-related type Ia, 12; gutter-related type Ib, 9; type Ia, 2; type Ic, 2; type III, 1; undetermined, 2) in 27 patients. The technical and clinical success rate was 37% and 30%, respectively. The mean follow-up for survival was 48 ± 31 months. The latest radiologic follow-up demonstrated 12 remaining and 1 new endoleak. The early and overall PG sealing zone failure and PG failure was 73% and 36% and 9% and 18%, respectively. The overall PG-TEVAR–related reintervention rate was 33% (n = 11). The estimated freedom from overall PG-TEVAR–related reintervention was 68% at 60 months. The main graft oversizing and length oversizing rates were not significantly associated statistically with the type Ia endoleak-related reintervention rate. The PG-TEVAR–related and all-cause mortality were 18% and 34%, respectively.
PG-TEVAR for total endovascular repair of arch-involving aortic pathologies resulted in a high rate of type I endoleaks and the need for long-term reintervention. Gutter-related endoleaks might be more frequent than reported and should not be underestimated because they can lead to sac enlargement and reintervention. Frequent radiologic surveillance is mandatory. Further studies comparing PG-TEVAR to other total endovascular alternatives are required to confirm these findings.
Mixed cropping has been suggested as a resource-efficient approach to meet high produce demands while maintaining biodiversity and minimizing environmental impact. Current breeding programs do not ...select for enhanced general mixing ability (GMA) and neglect biological interactions within species mixtures. Clear concepts and efficient experimental designs, adapted to breeding for mixed cropping and encoded into appropriate statistical models, are lacking. Thus, a model framework for GMA and SMA (specific mixing ability) was established. Results of a simulation study showed that an incomplete factorial design combines advantages of two commonly used full factorials, and enables to estimate GMA, SMA, and their variances in a resource-efficient way. This model was extended to the Producer (Pr) and Associate (As) concept to exploit additional information based on fraction yields. It was shown that the Pr/As concept allows to characterize genotypes for their contribution to total mixture yield, and, when relating to plant traits, allows to describe biological interaction functions (BIF) in a mixed crop. Incomplete factorial designs show the potential to drastically improve genetic gain by testing an increased number of genotypes using the same amount of resources. The Pr/As concept can further be employed to maximize GMA in an informed and efficient way. The BIF of a trait can be used to optimize species ratios at harvest as well as to extend our understanding of competitive and facilitative interactions in a mixed plant community. This study provides an integrative methodological framework to promote breeding for mixed cropping.
Mixed cropping (MC) is a key strategy to harness agriculture for climate-change. Breeding adapted genotypes can unleash the full potential of MC, both in terms of yield potential and yield stability. ...To achieve this goal, concepts from both breeding and ecology have to be fused in order to develop a suitable methodology for breeding for MC. In order to advance the field of breeding for MC, we evaluated yield and trait data of pure stands (PS) and mixed stands (MS) of pea (P. sativum L.) and barley (H. vulgare L.) as a legume-cereal model system. Twenty-eight pea and seven barley lines, representing European breeding material, were grown in an incomplete factorial design at two organically managed sites across two years. The general mixing ability (GMA) of pea for total mixture yield was predominant as specific mixing ability (SMA) was absent, facilitating future breeding and seed marketing efforts. The most promising pea cultivar ‘Volt’ resulted in an average total mixture yield increase of 11% (+0.43 t/ha) in MC compared to the average, while the cultivar ’Florida’ led to a yield decrease of − 31% (−1.23 t/ha), highlighting the importance of the choice of the genotype in MS. The analysis of separated MS yields allowed to investigate the underlying mechanistic principles in genotypes’ contribution to MS yields and we revealed the major role of producer (Pr) effects in this context. The correlation between Pr effects and GMA revealed that GMA can be maximized by selecting for high Pr effects. Early vigor, onset of flowering, shoot biomass and stipule length were identified as key traits for indirect selection for high GMA in pea accounting for up to 17% of the identified variation in total mixture yield. PS yields were moderately correlated with mixture yields (r = 0.52, P = 0.013) and can serve as an additional selection criterion. Discrepancies between correlations with PS and MS yields can be exploited to identify unique MS traits that confer niche complementarity in MS. By this method we identified stipule size as such a key trait for increasing GMA of pea. Pea genotype mixtures have a stabilizing effect also in MC systems and exhibited considerably less genotype × year and genotype × location interaction than single genotypes. Our findings close existing knowledge gaps towards breeding for MC and pave the way to develop improved genotypes for diversified cropping systems as a strategy for sustainable intensification and climate change adaptation.
•Higher genetic variances for general (GMA) than for specific (SMA) mixing ability.•Moderate correlation of pea pure stand with mixed crop (mixed within row) yield.•Producer effects were correlated to GMA and can be integrated in selection strategies.•Three morphological pea key traits were identified for indirect selection for GMA.•Diversification using mixed cropping & genotype mixtures increased yield stability.
Purpose: To compare open versus endovascular left subclavian artery debranching for thoracic endovascular aortic repair of thoracic aortic pathologies.Methods: This is a retrospective study of ...patients receiving left subclavian artery debranching in our institution from October 2009 to January 2020. The primary outcome was freedom from aortic reintervention. Secondary outcomes were type I endoleaks, left subclavian artery (LSA) debranching failure, stroke, technical or clinical success, procedure-related reintervention, as well as 30-day or overall all-cause and aorta-related mortality.Results: Forty-eight patients received parallel graft-based (n = 24, ENDO; median age 75 years 70–80 years) or open (n = 24, OPEN; median age 71 years 59–75 years) debranching for type B aortic dissection (n = 25), degenerative aneurysm (n = 12), type IA endoleak (n = 6), suture-associated (n = 3) or ostial LSA aneurysm (n = 1), or penetrating aortic ulcer (n = 1). The median follow-up was 36 months (13–61 months). After 16 months, aortic reintervention-free survival in groups OPEN and ENDO was 91% (95% confidence interval CI: 79 to 100%) and 86% (73 to 100%) (p = 0.71), respectively. After 36 months, all-cause survival in groups OPEN and ENDO was 74% (95% CI: 55 to 99%) and 79% (95% CI: 64 to 97%) (p = 0.74), respectively; freedom from aorta-related mortality was 81% (95% CI: 62 to 100%) and 91% (95% CI: 80 to 100%) (p = 0.78), respectively. Group OPEN presented less type I endoleaks (OPEN/ENDO = 3/19, p <0.001) and higher technical (OPEN/ENDO = 81/36%, p = 0.003) and clinical success rates (OPEN/ENDO = 67/36%, p = 0.047). No statistical differences were found for other outcomes.Conclusion: Both strategies achieved comparable reintervention and mortality rates, but open debranching should be preferred due to its higher technical and clinical success and less type I endoleaks.
Purpose: To compare open versus endovascular left subclavian artery debranching for thoracic endovascular aortic repair of thoracic aortic pathologies.Methods: This is a retrospective study of ...patients receiving left subclavian artery debranching in our institution from October 2009 to January 2020. The primary outcome was freedom from aortic reintervention. Secondary outcomes were type I endoleaks, left subclavian artery (LSA) debranching failure, stroke, technical or clinical success, procedure-related reintervention, as well as 30-day or overall all-cause and aorta-related mortality.Results: Forty-eight patients received parallel graft-based (n = 24, ENDO; median age 75 years 70–80 years) or open (n = 24, OPEN; median age 71 years 59–75 years) debranching for type B aortic dissection (n = 25), degenerative aneurysm (n = 12), type IA endoleak (n = 6), suture-associated (n = 3) or ostial LSA aneurysm (n = 1), or penetrating aortic ulcer (n = 1). The median follow-up was 36 months (13–61 months). After 16 months, aortic reintervention-free survival in groups OPEN and ENDO was 91% (95% confidence interval CI: 79 to 100%) and 86% (73 to 100%) (p = 0.71), respectively. After 36 months, all-cause survival in groups OPEN and ENDO was 74% (95% CI: 55 to 99%) and 79% (95% CI: 64 to 97%) (p = 0.74), respectively; freedom from aorta-related mortality was 81% (95% CI: 62 to 100%) and 91% (95% CI: 80 to 100%) (p = 0.78), respectively. Group OPEN presented less type I endoleaks (OPEN/ENDO = 3/19, p <0.001) and higher technical (OPEN/ENDO = 81/36%, p = 0.003) and clinical success rates (OPEN/ENDO = 67/36%, p = 0.047). No statistical differences were found for other outcomes.Conclusion: Both strategies achieved comparable reintervention and mortality rates, but open debranching should be preferred due to its higher technical and clinical success and less type I endoleaks.
The IceCube Neutrino Observatory is a cubic kilometer neutrino detector located at the geographic South Pole designed to detect high-energy astrophysical neutrinos. To thoroughly understand the ...detected neutrinos and their properties, the detector response to signal and background has to be modeled using Monte Carlo techniques. An integral part of these studies are the optical properties of the ice the observatory is built into. The simulated propagation of individual photons from particles produced by neutrino interactions in the ice can be greatly accelerated using graphics processing units (GPUs). In this paper, we (a collaboration between NVIDIA and IceCube) reduced the propagation time per photon by a factor of up to 3 on the same GPU. We achieved this by porting the OpenCL parts of the program to CUDA and optimizing the performance. This involved careful analysis and multiple changes to the algorithm. We also ported the code to NVIDIA OptiX to handle the collision detection. The hand-tuned CUDA algorithm turned out to be faster than OptiX. It exploits detector geometry and only a small fraction of photons ever travel close to one of the detectors.
PDF
