bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiscale fracture and damage zone characterization in a tight sandstone reservoir, Sichuan Basin, China
Authors: Liao Zonghu , Chen Weilun , Chen Xiaofeng , Zou Huayao , Hao Fang
Published: June 2020

Fractures within fault damage zones are crucial for the migration of subsurface fluids, which is challenging the characterization of the fractures and damage zones in the subsurface due to the lack of subsurface data. We have investigated the fractures and fault damage zones in the tight sandstone gas-bearing Xujiahe Formation in the northeast Sichuan Basin, China, based on a comprehensive study of seismic data, well log, core, as well as field observations. We have demonstrated the structure and distribution of damage zones from the basin-scale down to the microscale. The core samples find mostly opening-mode microfractures that can be subcritically generated under low tectonic stress fields since the Late Triassic-Middle Jurassic. These opening-mode microfractures in such ultra-low-permeability sandstone are likely to provide a storage volume for coal gas to accumulate. Macrofractures from image logging and outcrop display well-developed joint networks within the sandstone. The basin-wide distribution of such macrofractures implies potential conduits for gas migration during basin uplift in the Cretaceous. The damage zones are formed and controlled by a system of reverse faults, with thicknesses ranging 100–1500 m. The multiscale analysis of fractures implies that, for the tight sandstone within the Xujiahe Formation, the fractures and damage zones are likely to control the gas migration and accumulation during the tectonic transformation from the Late Cretaceous to the Quaternary Period. The overpressure history, coupled with the fracture system, enhances the redistribution of the gas reservoir. This approach and these data lead to a more in-depth understanding of the fractures and damage zones on a regional scale, which could extend to hydraulic and mechanical characterization of damage zones in the upper crust.
Characterizing damage zones of normal faults using seismic variance in the Wangxuzhuang oilfield, China
Authors: Liao Zonghu , Hu Luyao , Huang Xiaodi , Carpenter Brett M. , Marfurt Kurt J. , Vasileva Saiyyna , Zhou Yun
Published: June 2020

We have investigated the distribution and thickness of damage zones for a system of secondary normal faults in the subsurface of the Wangxuzhuang oilfield, China. Based on seismic variance analysis, we find (1) four isolated faults with approximately 2 km length and approximately 200 m damage-zone thickness. The damage zones of these isolated faults reveal a decaying intensity of deformation from the fault core to the protolith, which fits a power-law form [Formula: see text] similar to that observed in the field. (2) A merged fault with approximately 400 m thickness. (3) A bifurcated fault with approximately 400 m thickness and three linked segments. Damage zones that consist of several subsidiary faults are thicker than those of isolated faults. The displacement-length analyses of the four isolated faults suggest the constant-length growth of the limestone in this case. We determine the potential to apply seismic variance to systematically characterize damage zones as potential fluid migration conduits on the basin scale.
Predicting Mortality Due to SARS-CoV-2: A Mechanistic Score Relating Obesity and Diabetes to COVID-19 Outcomes in Mexico
Authors: Bello-Chavolla Omar Yaxmehen , Bahena-López Jessica Paola , Antonio-Villa Neftali Eduardo , Vargas-Vázquez Arsenio , González-Díaz Armando , Márquez-Salinas Alejandro , Fermín-Martínez Carlos A , Naveja J Jesús , Aguilar-Salinas Carlos A
Published: May 2020

Background

The SARS-CoV-2 outbreak poses a challenge to health care systems due to its high complication rates in patients with cardiometabolic diseases. Here, we identify risk factors and propose a clinical score to predict COVID-19 lethality, including specific factors for diabetes and obesity, and its role in improving risk prediction.

Methods

We obtained data of confirmed and negative COVID-19 cases and their demographic and health characteristics from the General Directorate of Epidemiology of the Mexican Ministry of Health. We investigated specific risk factors associated to COVID-19 positivity and mortality and explored the impact of diabetes and obesity on modifying COVID-19-related lethality. Finally, we built a clinical score to predict COVID-19 lethality.

Results

Among the 177 133 subjects at the time of writing this report (May 18, 2020), we observed 51 633 subjects with SARS-CoV-2 and 5,332 deaths. Risk factors for lethality in COVID-19 include early-onset diabetes, obesity, chronic obstructive pulmonary disease, advanced age, hypertension, immunosuppression, and chronic kidney disease (CKD); we observed that obesity mediates 49.5% of the effect of diabetes on COVID-19 lethality. Early-onset diabetes conferred an increased risk of hospitalization and obesity conferred an increased risk for intensive care unit admission and intubation. Our predictive score for COVID-19 lethality included age ≥ 65 years, diabetes, early-onset diabetes, obesity, age < 40 years, CKD, hypertension, and immunosuppression and significantly discriminates lethal from non-lethal COVID-19 cases (C-statistic = 0.823).

Conclusions

Here, we propose a mechanistic approach to evaluate the risk for complications and lethality attributable to COVID-19, considering the effect of obesity and diabetes in Mexico. Our score offers a clinical tool for quick determination of high-risk susceptibility patients in a first-contact scenario.
Perinuclear mitochondrial clustering, increased ROS levels, and HIF1 are required for the activation of HSF1 by heat stress
Authors: Agarwal Saloni , Ganesh Subramaniam
Published: June 2020

The heat shock response (HSR) is a conserved cellular defensive response against stresses such as temperature, oxidative stress and heavy metals. A significant group of players in the HSR is the set of molecular chaperones known as heat shock proteins (HSPs), which assist in the refolding of unfolded proteins and prevent the accumulation of damaged proteins. HSP genes are activated by the HSF1 transcription factor, a master regulator of the HSR pathway. A variety of stressors activate HSF1, but the key molecular players and the processes that directly contribute to HSF1 activation remain unclear. In this study, we show that heat shock induces perinuclear clustering of mitochondria in mammalian cells, and this clustering is essential for activation of the HSR. We also show that this perinuclear clustering of mitochondria results in increased levels of reactive oxygen species in the nucleus, leading to the activation of hypoxia-inducible factor-1α (HIF-1α). To conclude, we provide evidence to suggest that HIF-1α is one of the crucial regulators of HSF1 and that HIF-1α is essential for activation of the HSR during heat shock.
Giant villous adenoma of the sigmoid colon: an unusual cause of homogeneous, segmental bowel wall thickening
Authors: Sacks Jeffrey , Atlas Seymour , Enno Alar , Santos Leonardo , Humphries Jeremy , Kirwan Alexander
Published: June 2020

Colonic adenomas are commonly encountered lesions that are a precursor of colorectal cancer. Of these, villous adenomas are a rarer, more advanced subtype that are larger in size than tubular adenomas and have a higher risk of malignant transformation. We present a patient with a giant villous adenoma of the sigmoid colon identified on CT as homogeneous segmental bowel wall thickening.
РАЗРАБОТКА СИСТЕМЫ ОЦЕНКИ МАРКЕТИНГОВОЙ ДЕЯТЕЛЬНОСТИ СРЕДСТВАМИ ПЛАТФОРМЫ 1С: ПРЕДПРИЯТИЕ
Authors: Eremina Irina Ilinichna , Ishmuradova Izida Ildarovna , Lysanov Denis Mihailovich
Published: May 2020

Представленное исследование посвящено разработке автоматизированной информационной системы оценки эффективности маркетинговых мероприятий, выявлены особенностей разработки информационной системы эффективности проведения маркетинговых мероприятий, с учетом динамики влияния внешних и внутренних факторов средствами платформы 1С: Предприятие.
РАЗРАБОТКА УПРАВЛЯЮЩИХ КОНФИГУРАЦИЙ SCADA ДЛЯ СИСТЕМЫ ЖКХ
Authors: Lysanov Denis Mihailovich , Eremina Irina Ilinichna , Ishmuradova Izida Ildarovna
Published: May 2020

Статья посвящается особенностям применения системы SCADA для создания конфигураций дистанционного управления разными промышленными приборами. Это оборудование работает в режиме реального времени, где по каждому установленному датчику видно, что происходит в текущий момент и позволяет быстро реагировать на нестандартные ситуации и осуществлять регулирование параметров приборов в отдельности и системы в целом.
ОБ ОПТИМИЗАЦИИ СИСТЕМЫ ПЕРЕВОЗОК НА ОСНОВЕ МОНИТОРИНГОВОЙ ИНФОРМАЦИИ
Authors: Lvovich Yakov Yevseevich , Preobrazhenskiy Andrey Petrovich , Choporov Oleg Nikolaevich
Published: May 2020

В статье рассматривается задача, в которой требуется оптимизировать систему перевозок. При этом необходимо опираться на мониторинговую информацию. Приведена схема работы сетевых компонентов системы перевозок при учете мониторинговой информации.
ВЛИЯНИЕ ТРАНСПОРТНОЙ ИНФРАСТРУКТУРЫ НА УСТОЙЧИВОЕ РАЗВИТИЕ: ТЕНДЕНЦИИ И ПРОБЛЕМЫ
Authors: Berman Nina Demidovna
Published: May 2020

Устойчивое развитие является ключевой концепцией нашего времени. Транспортная инфраструктура относится к системообразующим секторам экономики, связана со всеми ее элементами, от которых зависит устойчивое ее развитие. В статье рассматриваются влияния транспортной инфраструктуры на устойчивое развитие, показаны возникающие тенденции и проблемы.
Simultaneity of unhealthy behaviors associated with hypertension among Brazilian adults
Authors: Santos Priscila Cristina , Del Duca Giovani Firpo , Silva Kelly Samara da , Costa Rafael Martins da , Streb Anne Ribeiro , Gerage Aline Mendes , Malta Debora Carvalho
Published: May 2020

It is well known that some unhealthy behaviors are potentially associated with hypertension, but it is not known which combinations of simultaneous behaviors increase the chance of developing hypertension. In addition, more evidence is needed to assist in the development of preventive public policies in low- and middle-income countries. Thus, the objective was to determine the association between the clustering of four unhealthy behaviors and the occurrence of hypertension among Brazilian adults. The secondary data analyzed are derived from VIGITEL 2015 database, a cross-sectional national surveillance that included 35,548 adults aged 18 to 59 years living in Brazilian state capitals. Unhealthy behaviors and hypertension were measured by self-report. Sixteen combinations based on the presence and absence of the four unhealthy behaviors were performed and binary logistic regression was used to determine the association between simultaneity of these behaviors and hypertension. The odds to have all unhealthy behaviors were 3.50 (95%CI: 2.96 - 4.10) times higher than the expected value if unhealthy behaviors were independent. Adults with simultaneous all risk behaviors (OR = 2.42; 95%CI: 1.20 - 4.85), with excessive salt consumption and physical inactivity (OR = 1.41; 95%CI: 1.11 - 1.80) and with excessive alcohol consumption and physical inactivity (OR =1.60; 95%CI: 1.14 - 2.25) were more likely to have hypertension compared to the people without unhealthy behaviors. In conclusion, some combinations of unhealthy behaviors were actually more dangerous for hypertension in the investigated population. Future public policies to prevent hypertension can be more effective if to focus on simultaneity of unhealthy behaviors that increased the chance of developing the disease, especially physical inactivity.
Alterações na antropometria e na qualidade de vida relacionada à saúde após um programa de exercícios aquáticos em crianças com sobrepeso e obesidade
Authors: Reis Marina de Melo , Lemes Thiago Matheus Mendes Alves e , Viana Raytta Silva , Andaki Alynne Christian Ribeiro
Published: May 2020

O objetivo do estudo foi avaliar as alterações, após um programa de exercícios aquáticos, dos parâmetros antropométricos e de qualidade de vida relacionada à saúde (QVRS) em crianças com sobrepeso ou obesidade. Trata-se de um ensaio clínico não-randomizado e controlado realizado na cidade de Uberaba, Minas Gerais com participação de 33 crianças com média de idade de 9,10 ± 1,00 anos, de ambos os sexos. As crianças foram alocadas em grupo controle (GC, n = 21) e grupo experimental (GE, n = 12). O GE realizou 21 semanas de exercícios aquáticos de caráter aeróbio recreativo, 54 sessões de 60 minutos cada. No baseline e pós-intervenção, foram avaliados massa corporal, estatura, IMC e QVRS por meio do Questionário Pediátrico de Qualidade de Vida (Pedsql versão 4.0). Observou-se efeito significativo do tempo no aspecto emocional da QVRS relatada pelos filhos (p = 0,009), houve redução dos escores do GE e aumento nos escores do GC. Na dimensão atividade escolar houve tendência para interação tempo*grupo (p = 0,059), em que observamos redução dos escores no GE e aumento no GC após 21 semanas. Em relação à antropometria e QVRS relatada pelos pais, não foram observadas diferenças significativas em ambos os grupos. Em conclusão, houve alterações significativas na dimensão emocional relatado pelas crianças, porém, a intervenção não alterou significativamente a antropometria e demais dimensões da QVRS de crianças com sobrepeso ou obesidade.
Correlation between patient-reported outcome measures and Single Assessment Numerical Evaluation score in patients treated with a volar locking plate for a distal radial fracture
Authors: Choi Wan-Sun , Hwang Ji Sun , Hur Jae-Seung , Lee Chang-Hun , Kim Joo-Hak , Lee Kwang-Hyun
Published: May 2020

Aims

The aim of this study was to compare patient-reported outcome measures (PROMs) and the Single Assessment Numerical Evaluation (SANE) score in patients treated with a volar locking plate for a distal radial fracture.

Methods

This study was a retrospective review of a prospective database of 155 patients who underwent internal fixation with a volar locking plate for a distal radial fracture between August 2014 and April 2017. Data which were collected included postoperative PROMs (Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH) and Patient-Rated Wrist Evaluation (PRWE)), and SANE scores at one month (n = 153), two months (n = 155), three months (n = 144), six months (n = 128), and one year (n = 73) after operation. Patients with incomplete data were excluded from this study. Correlation and agreement between PROMs and SANE scores were evaluated. Subgroup analyses were carried out to identify correlations according to variables such as age, the length of follow-up, and subcategories of the PRWE score.

Results

The Pearson correlation coefficient (r) between PROMs and SANE scores was -0.76 (p < 0.001) for DASH and -0.72 (p < 0.001) for PRWE, respectively. Limits of agreement between PROMs and ‘100-SANE’ scores were met for at least 93% of the data points. In subgroup analysis, there were significant negative correlations between PROMs and SANE scores for all age groups and for follow-up of more than six months. The correlation coefficient between PRWE subcategories and SANE score was -0.67 (p < 0.001) for PRWE pain score and -0.69 (p < 0.001) for PRWE function score, respectively.

Conclusion

We found a significant correlation between postoperative SANE and PROMs in patients treated with a volar locking plate for a distal radial fracture. The SANE score is thus a reliable indicator of outcome for patients who undergo surgical treatment for a radial fracture. Cite this article: Bone Joint J 2020;102-B(6):744–748.
Transepiphyseal resection for osteosarcoma in patients with open physes using MRI assessment
Authors: Kim Yongsung , Jang Woo Young , Park Jong Woong , Park Yeong Kyoon , Cho Hwan Seong , Han Ilkyu , Kim Han-Soo
Published: May 2020

Aims

For paediatric and adolescent patients with growth potential, preservation of the physiological joint by transepiphyseal resection (TER) of the femur confers definite advantages over arthroplasty procedures. We hypothesized that the extent of the tumour and changes in its extent after neoadjuvant chemotherapy are essential factors in the selection of this procedure, and can be assessed with MRI. The oncological and functional outcomes of the procedure were reviewed to confirm its safety and efficacy.

Methods

We retrospectively reviewed 16 patients (seven male and nine female, mean age 12.2 years (7 to 16)) with osteosarcoma of the knee who had been treated by TER. We evaluated the MRI scans before and after neoadjuvant chemotherapy for all patients to assess the extent of the disease and the response to treatment.

Results

The mean follow-up period was 64.3 months (25 to 148) after surgery and no patients were lost to follow-up. On MRI evaluation, 13 tumours were near but not in contact with the physes and three tumours were partially in contact with the physes before neoadjuvant chemotherapy. Bone oedema in the epiphysis was observed in eight patients. After neoadjuvant chemotherapy, bone oedema in the epiphysis disappeared in all patients. In total, 11 tumours were not in contact and five tumours were in partial contact with the physes. The postoperative pathological margin was negative in all patients. At the last follow-up, 12 patients were continuously disease-free and three had no evidence of disease. One patient died due to the disease. Functionally, the patients with retained allograft or recycled autograft had a mean knee range of flexion of 126° (90° to 150°). The mean Musculoskeletal Tumor Society functional score was 27.6 (23 to 30).

Conclusion

TER is an effective limb-salvage technique for treating malignant metaphyseal bone tumours in paediatric and young osteosarcoma patients with open physes when a good response to chemotherapy and no progression of the tumour to the epiphysis have been confirmed by MRI. Cite this article: Bone Joint J 2020;102-B(6):772–778.
The correlation between shape of the sigmoid notch of the distal radius and the risk of triangular fibrocartilage complex foveal tear
Authors: Jung Hyoung-Seok , Park Min J. , Won Yoo-Sun , Lee Guen Y. , Kim Sujin , Lee Jae S.
Published: May 2020

Aims

The aim of this study was to analyze the association between the shape of the distal radius sigmoid notch and triangular fibrocartilage complex (TFCC) foveal tear.

Methods

Between 2013 and 2018, patients were retrospectively recruited in two different groups. The patient group comprised individuals who underwent arthroscopic transosseous TFCC foveal repair for foveal tear of the wrist. The control group comprised individuals presenting with various diseases around wrist not affecting the TFCC. The study recruited 176 patients (58 patients, 118 controls). The sigmoid notch shape was classified into four types (flat-face, C-, S-, and ski-slope types) and three radiological parameters related to the sigmoid notch (namely, the radius curvature, depth, and version angle) were measured. The association of radiological parameters and sigmoid notch types with the TFCC foveal tear was investigated in univariate and multivariate analyses. Receiver operating characteristic curves were used to estimate a cut-off for any statistically significant variables.

Results

Univariate analysis showed that the flat-face type was more prevalent in the patients than in the control group (43% vs 21%; p = 0.002), while the C-type was lower in the patients than in the control group (3% vs 17%; p = 0.011). The depth and version angle of sigmoid notch showed a negative association with the TFCC foveal tear in the multivariate analysis (depth: odds ratio (OR) 0.380; p = 0.037; version angle: OR 0.896; p = 0.033). Estimated cut-off values were 1.34 mm for the depth (area under the curve (AUC) = 0.725) and 10.45° for the version angle (AUC = 0.726).

Conclusion

The proportion of flat-face sigmoid notch type was greater in the patient group than in the control group. The depth and version angle of sigmoid notch were negatively associated with TFCC foveal injury. Cite this article: Bone Joint J 2020;102-B(6):749–754.
Surgical and oncological outcomes after hindquarter amputation for pelvic sarcoma
Authors: Kiiski Juha , Parry Michael C. , Le Nail Luis-Romee , Sumathi Vaiyapuri , Stevenson Jonathan D. , Kaartinen Ilkka S. , Jeys Lee M. , Laitinen Minna K.
Published: May 2020

Aims

Survival rates and local control after resection of a sarcoma of the pelvis compare poorly to those of the limbs and have a high incidence of complications. The outcome for patients who need a hindquarter amputation (HQA) to treat a pelvic sarcoma is poor. Our aim was to evaluate the patient, tumour, and reconstructive factors that affect the survival of the patients who undergo HQA for primary or recurrent pelvic sarcoma.

Methods

We carried out a retrospective review of all sarcoma patients who had undergone a HQA in a supraregional sarcoma unit between 1996 and 2018. Outcomes included oncological, surgical, and survival characteristics.

Results

A total of 136 patients, with a mean age of 51 (12 to 83) underwent HQA, 91 for a bone sarcoma and 45 for a soft tissue sarcoma. The overall survival (OS) after primary HQA for a bone sarcoma was 90.7 months (95% confidence interval (CI) 64.1 to 117.2). In patients undergoing a secondary salvage HQA it was 90.3 months (95% CI 58.1 to 122.5) (p = 0.727). For those treated for a soft tissue sarcoma (STS), the mean OS was 59.3 months (95% CI 31.1 to 88.6) for patients with a primary HQA, and 12.5 months (95% CI 9.4 to 15.5) for those undergoing a secondary salvage HQA (p = 0.038). On multivariate analysis, high histological grade (hazard ratio (HR) 2.033, 95% CI 1.127 to 3.676; p = 0.018) and a diagnosis of STS (HR 1.653, 95% CI 1.027 to 2.660; p = 0.039) were associated with a poor prognosis. The 30-day mortality for patients with curative intent was 0.8% (1/128). For those in whom surgery was carried out with palliative intent it was 33.3% (2/6) (p = 0.001). In total, 53.7% (n = 73) of patients had at least one complication with 23.5% (n = 32) requiring at least one further operation. Direct closure was inferior to flap reconstruction in terms of complete primary wound healing (60.0% (3/5) vs 82.0% (82/100); p = 0.023).

Conclusion

In carefully selected patients HQA is associated with satisfactory overall survival, with a low risk of perioperative mortality, but considerable morbidity. However, caution must be exercised when considering the procedure for palliation due to the high incidence of early postoperative mortality. Cite this article: Bone Joint J 2020;102-B(6):788–794.
2020 Chitranjan S. Ranawat Award: Perioperative essential amino acid supplementation suppresses rectus femoris muscle atrophy and accelerates early functional recovery following total knee arthroplasty
Authors: Ueyama Hideki , Kanemoto Narihiro , Minoda Yukihide , Taniguchi Yoshiki , Nakamura Hiroaki
Published: May 2020

Aims

The aim of this study was to assess the effectiveness of perioperative essential amino acid (EAA) supplementation to prevent rectus femoris muscle atrophy and facilitate early recovery of function after total knee arthroplasty (TKA).

Methods

The study involved 60 patients who underwent unilateral TKA for primary knee osteo-arthritis (OA). This was a double-blind, placebo-controlled, randomized control trial with patients randomly allocated to two groups, 30 patients each: the essential amino acid supplementation (9 g daily) and placebo (lactose powder, 9 g daily) groups. Supplementation and placebo were provided from one week before to two weeks after surgery. The area of the rectus femoris muscle were measured by ultrasound imaging one month before surgery and one, two, three, and four weeks postoperatively. The serum albumin level, a visual analogue knee pain score, and mobility were also measured at each time point. The time to recovery of activities of daily living (ADLs) was recorded. Postoperative nutrition and physiotherapy were identical in both groups.

Results

The mean relative change from baseline was as follows for the amino acid group: 116% in rectus femoris muscle area (71% to 206%); 95% in serum albumin (80% to 115%) and 39% in VAS pain (0% to 100%) at four weeks after surgery. These values in the placebo group were: 97% in muscle area (68 to 155); 89% in serum albumin (71% to 100%) and 56% in VAS pain four weeks after surgery (0% to 100%). All changes were statistically significant (p < 0.05). The mean time to recovery of ADLs was shorter in the amino acid group compared with the placebo group (p = 0.005).

Conclusion

Perioperative essential amino acid supplementation prevents rectus femoris muscle atrophy and accelerates early functional recovery after TKA. Cite this article: Bone Joint J 2020;102-B(6 Supple A):10–18.
Health-related quality of life after paediatric supracondylar humeral fractures
Authors: Liebs Thoralf R. , Burgard Marie , Kaiser Nadine , Slongo Theddy , Berger Steffen , Ryser Basil , Ziebarth Kai
Published: May 2020

Aims

We aimed to evaluate the health-related quality of life (HRQoL) in children with supracondylar humeral fractures (SCHFs), who were treated following the recommendations of the Paediatric Comprehensive AO Classification, and to assess if HRQoL was associated with AO fracture classification, or fixation with a lateral external fixator compared with closed reduction and percutaneous pinning (CRPP).

Methods

We were able to follow-up on 775 patients (395 girls, 380 boys) who sustained a SCHF from 2004 to 2017. Patients completed questionnaires including the Quick Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH; primary outcome), and the Pediatric Quality of Life Inventory (PedsQL).

Results

An AO type I SCHF was most frequent (327 children; type II: 143; type III: 150; type IV: 155 children). All children with type I fractures were treated nonoperatively. Two children with a type II fracture, 136 with a type III fracture, and 141 children with a type IV fracture underwent CRPP. In the remaining 27 children with type III or IV fractures, a lateral external fixator was necessary for closed reduction. There were no open reductions. After a mean follow-up of 6.3 years (SD 3.7), patients with a type I fracture had a mean QuickDASH of 2.0 (SD 5.2), at a scale of 0 to 100, with lower values representing better HRQoL (type II: 2.8 (SD 10.7); type III: 3.3 (SD 8.0); type IV: 1.8 (SD 4.6)). The mean function score of the PedsQL ranged from 97.4 (SD 8.0) for type I to 96.1 (SD 9.1) for type III fractures, at a scale of 0 to 100, with higher values representing better HRQoL.

Conclusion

In this cohort of 775 patients in whom nonoperative treatment was chosen for AO type I and II fractures and CRPP or a lateral external fixator was used in AO type III and IV fractures, there was equally excellent mid- and long-term HRQoL when assessed by the QuickDASH and PedsQL. These results indicate that the treatment protocol followed in this study is unambiguous, avoids open reductions, and is associated with excellent treatment outcomes. Cite this article: Bone Joint J 2020;102-B(6):755–765.
What is the impact of patellofemoral joint degeneration and malalignment on patient-reported outcomes after lateral unicompartmental knee arthroplasty?
Authors: Burger Joost A. , Dooley Matthew S. , Kleeblad Laura J. , Zuiderbaan Hendrik A. , Pearle Andrew D.
Published: May 2020

Aims

It remains controversial whether patellofemoral joint pathology is a contraindication to lateral unicompartmental knee arthroplasty (UKA). This study aimed to evaluate the effect of preoperative radiological degenerative changes and alignment on patient-reported outcome scores (PROMs) after lateral UKA. Secondarily, the influence of lateral UKA on the alignment of the patellofemoral joint was studied.

Methods

A consecutive series of patients who underwent robotic arm-assisted fixed-bearing lateral UKA with at least two-year follow-up were retrospectively reviewed. Radiological evaluation was conducted to obtain a Kellgren Lawrence (KL) grade, an Altman score, and alignment measurements for each knee. Postoperative PROMs were assessed using the Kujala (Anterior Knee Pain Scale) score, Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS JR), and satisfaction levels.

Results

A total of 140 knees (130 patients) were identified for analysis. At mean 4.1 years (2.0 to 8.5) follow-up, good to excellent Kujala scores were reported. The presence of mild to moderate preoperative patellofemoral joint osteoarthritis had no impact on these scores (KL grade 0 vs 1 to 3, p = 0.203; grade 0 to 1 vs 2 to 3, p = 0.674). Comparable scores were reported by patients with osteoarthritis (Altman score of ≥ 2) evident on either the medial or lateral patellofemoral joint facet (medial, p = 0.600 and lateral, p = 0.950). Patients with abnormal patellar congruence and tilt angles (≥ 17° and ≥ 14°, respectively) reported good to excellent Kujala scores. Furthermore, lateral UKA resulted in improvements to patellofemoral alignment.

Conclusion

This is the first study demonstrating that mild to moderate preoperative radiological degenerative changes and malalignment of the patellofemoral joint are not associated with poor patient-reported outcomes at mid-term follow-up after lateral fixed-bearing UKA. Our data suggest that this may be explained by realignment of the patella and thereby redistribution of loads across the patellofemoral joint. Cite this article: Bone Joint J 2020;102-B(6):727–735.
Treatment of displaced intracapsular fractures of the femoral neck with total hip arthroplasty or hemiarthroplasty
Authors: Viswanath Aparna , Malik Anum , Chan Warwick , Klasan Antonio , Walton Neil P.
Published: May 2020

Aims

Despite few good-quality studies on the subject, total hip arthroplasty (THA) is increasingly being performed for displaced intracapsular fractures of the neck of femur. We compared outcomes of all patients with displacement of these fractures treated surgically over a ten-year period in one institution.

Methods

A total of 2,721 patients with intracapsular fractures of the femoral neck treated with either a cemented hemiarthroplasty or a THA at a single centre were retrospectively reviewed. The primary outcomes analyzed were readmission for any reason and revision surgery. We secondarily looked at mortality rates.

Results

We found no difference in the overall revision rate or rate of infection. However, the rates of readmission due to dislocation, pain, and trochanteric bursitis were significantly higher in the THA group (p = 0.001, p < 0.001, p < 0.001, and p = 0.001, respectively).

Conclusion

Our study, comparing the outcomes of neck of femur fractures treated with a cemented hemiarthroplasty and THA, revealed the perceived superiority of THA was not borne out by our results. This should be carefully considered before any radical change in practice regarding the use of THA for displaced intracapsular fractures of the femoral neck. Cite this article: Bone Joint J 2020;102-B(6):693–698.
Obesity and hypoalbuminaemia are independent risk factors for readmission and reoperation following primary total knee arthroplasty
Authors: Sloan Matthew , Sheth Neil P. , Nelson Charles L.
Published: May 2020

Aims

Rates of readmission and reoperation following primary total knee arthroplasty (TKA) are under scrutiny due to new payment models, which penalize these negative outcomes. Some risk factors are more modifiable than others, and some conditions considered modifiable such as obesity may not be as modifiable in the setting of advanced arthritis as many propose. We sought to determine whether controlling for hypoalbuminaemia would mitigate the effect that prior authors had identified in patients with obesity.

Methods

We reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for the period of January 2008 to December 2016 to evaluate the rates of reoperation and readmission within 30 days following primary TKA. Multivariate logistic regression modelling controlled for preoperative albumin, age, sex, and comorbidity status.

Results

Readmission rates only differed significantly between patients with Normal Weight and Obesity Class II, with a decreased rate of readmission in this group (odds ratio (OR) 0.82; 95% confidence interval (CI) 0.71 to 0.96; p = 0.010). The only group demonstrating association with increased risk of reoperation within 30 days was the Obesity Class III group (OR 1.38; 95% CI 1.05 to 1.82; p = 0.022). Hypoalbuminaemia (preoperative albumin < 35 g/L) was significantly associated with readmission (OR 1.62; 95% CI 1.41 to 1.86; p < 0.001) and reoperation (OR 1.52; 95% CI 1.18 to 1.96; p = 0.001) within 30 days.

Conclusion

In this study, hypoalbuminaemia appears to be a more significant risk factor for readmission and reoperation than even the highest obesity categories. Future studies may assess whether preoperative albumin restoration or weight loss may improve outcomes for patients with hypoalbuminaemia. The implications of this study may allow surgeons to discuss risk of surgery with obese patients planning to undergo primary TKA procedures if other comorbidities are adequately controlled. Cite this article: Bone Joint J 2020;102-B(6 Supple A):31–35.
Outcomes of a technique combining diaphyseal impaction grafting and metaphyseal cones for severe bone loss in revision total knee arthroplasty
Authors: Bedard Nicholas A. , Cates Robert A. , Lewallen David G. , Sierra Rafael J. , Hanssen Arlen D. , Berry Daniel J. , Abdel Matthew P.
Published: May 2020

Aims

Metaphyseal cones with cemented stems are frequently used in revision total knee arthroplasty (TKA). However, if the diaphysis has been previously violated, the resultant sclerotic canal can impair cemented stem fixation, which is vital for bone ingrowth into the cone, and long-term fixation. We report the outcomes of our solution to this problem, in which impaction grafting and a cemented stem in the diaphysis is combined with an uncemented metaphyseal cone, for revision TKA in patients with severely compromised bone.

Methods

A metaphyseal cone was combined with diaphyseal impaction grafting and cemented stems for 35 revision TKAs. There were two patients with follow-up of less than two years who were excluded, leaving 33 procedures in 32 patients in the study. The mean age of the patients at the time of revision TKA was 67 years (32 to 87); 20 (60%) were male. Patients had undergone a mean of four (1 to 13) previous knee arthroplasty procedures. The indications for revision were aseptic loosening (80%) and two-stage reimplantation for prosthetic joint infection (PJI; 20%). The mean follow-up was four years (2 to 11).

Results

Survival free from revision of the cone/impaction grafting construct due to aseptic loosening was 100% at five years. Survival free from any revision of the construct and free from any reoperation were 92% and 73% at five years, respectively. A total of six patients (six TKAs, 17%) required a further revision, four for infection or wound issues, and two for periprosthetic fracture. Radiologically, one unrevised TKA had evidence of loosening which was asymptomatic. In all unrevised TKAs the impacted diaphyseal bone graft appeared to be incorporated radiologically.

Conclusion

When presented with a sclerotic diaphysis and substantial metaphyseal bone loss, this technique combining diaphyseal impaction grafting with a metaphyseal cone provided near universal success in relation to implant fixation. Moreover, radiographs revealed incorporation of the bone graft and biological fixation of the cone. While long-term follow-up will be important, this technique provides an excellent option for the management of complex revision TKAs. Cite this article: Bone Joint J 2020;102-B(6 Supple A):116–122.
Excessive flexed position of the femoral component was associated with poor new Knee Society Score after total knee arthroplasty with the Bi-Surface knee prosthesis
Authors: Nishitani Kohei , Kuriyama Shinichi , Nakamura Shinichiro , Umatani Naoki , Ito Hiromu , Matsuda Shuichi
Published: May 2020

Aims

This study aimed to evaluate the association between the sagittal alignment of the femoral component in total knee arthroplasty (TKA) and new Knee Society Score (2011KSS), under the hypothesis that outliers such as the excessive extended or flexed femoral component were related to worse clinical outcomes.

Methods

A group of 156 knees (134 F:22 M) in 133 patients with a mean age 75.8 years (SD 6.4) who underwent TKA with the cruciate-substituting Bi-Surface Knee prosthesis were retrospectively enrolled. On lateral radiographs, γ angle (the angle between the distal femoral axis and the line perpendicular to the distal rear surface of the femoral component) was measured, and the patients were divided into four groups according to the γ angle. The 2011KSSs among groups were compared using the Kruskal-Wallis test. A secondary regression analysis was used to investigate the association between the 2011KSS and γ angle.

Results

According to the mean and SD of γ angle (γ, 4.0 SD 3.0°), four groups (Extended or minor flexed group, −0.5° ≤ γ < 2.5° (n = 54)), Mild flexed group (2.5° ≤ γ < 5.5° (n = 63)), Moderate flexed group (5.5° ≤ γ < 8.5° (n = 26)), and Excessive flexed group (8.5° ≤ γ (n = 13)) were defined. The Excessive flexed group showed worse 2011KSSs in all subdomains (Symptoms, Satisfaction, Expectations, and Functional activities) than the Mild flexed group. Secondary regression showed a convex upward function, and the scores were highest at γ = 3.0°, 4.0°, and 3.0° in Satisfaction, Expectations, and Functional activities, respectively.

Conclusion

The groups with a sagittal alignment of the femoral component > 8.5° showed inferior clinical outcomes in 2011KSSs. Secondary regression analyses showed that mild flexion of the femoral component was associated with the highest score. When implanting the Bi-Surface Knee prosthesis surgeons should pay careful attention to avoiding flexing the femoral component extensively during TKA. Our findings may be applicable to other implant designs. Cite this article: Bone Joint J 2020;102-B(6 Supple A):36–42.
Tibial tray rotation and posterior slope increase risk for outliers in coronal alignment
Authors: D’Lima Dominique P. , Huang Philip , Suryanarayan Pichai , Rosen Adam , D’Lima Darryl D.
Published: May 2020

Aims

The extensive variation in axial rotation of tibial components can lead to coronal plane malalignment. We analyzed the change in coronal alignment induced by tray malrotation.

Methods

We constructed a computer model of knee arthroplasty and used a virtual cutting guide to cut the tibia at 90° to the coronal plane. The virtual guide was rotated axially (15° medial to 15° lateral) and with posterior slopes (0° to 7°). To assess the effect of axial malrotation, we measured the coronal plane alignment of a tibial tray that was axially rotated (25° internal to 15° external), as viewed on a standard anteroposterior (AP) radiograph.

Results

Axial rotation of the cutting guide induced a varus-valgus malalignment up to 1.8° (for 15° of axial rotation combined with 7° of posterior slope). Axial malrotation of tibial tray induced a substantially higher risk of coronal plane malalignment ranging from 1.9° valgus with 15° external rotation, to over 3° varus with 25° of internal rotation. Coronal alignment of the tibial cut changed by 0.07° per degree of axial rotation and 0.22° per degree of posterior slope (linear regression, R2> 0.99).

Conclusion

While the effect of axial malalignment has been studied, the impact on coronal alignment is not known. Our results indicate that the direction of the cutting guide and malalignment in axial rotation alter coronal plane alignment and can increase the incidence of outliers. Cite this article: Bone Joint J 2020;102-B(6 Supple A):43–48.
Excellent two-year survivorship of 3D-printed metaphyseal cones in revision total knee arthroplasty
Authors: Tetreault Matthew W. , Perry Kevin I. , Pagnano Mark W. , Hanssen Arlen D. , Abdel Matthew P.
Published: May 2020

Aims

Metaphyseal fixation during revision total knee arthroplasty (TKA) is important, but potentially difficult when using historical designs of cone. Material and manufacturing innovations have improved the size and shape of the cones which are available, and simplified the required bone preparation. In a large series, we assessed the implant survivorship, radiological results, and clinical outcomes of new porous 3D-printed titanium metaphyseal cones featuring a reamer-based system.

Methods

We reviewed 142 revision TKAs in 139 patients using 202 cones (134 tibial, 68 femoral) which were undertaken between 2015 and 2016. A total of 60 involved tibial and femoral cones. Most cones (149 of 202; 74%) were used for Type 2B or 3 bone loss. The mean age of the patients was 66 years (44 to 88), and 76 (55 %) were female. The mean body mass index (BMI) was 34 kg/m2(18 to 60). The patients had a mean of 2.4 (1 to 8) previous operations on the knee, and 68 (48%) had a history of prosthetic infection. The mean follow-up was 2.4 years (2 to 3.6).

Results

Survivorship free of cone revision for aseptic loosening was 100% and survivorship free of any cone revision was 98%. Survivorships free of any revision and any reoperation were 90% and 83%, respectively. Five cones were revised: three for infection, one for periprosthetic fracture, and one for aseptic tibial loosening. Radiologically, three unrevised femoral cones appeared loose in the presence of hinged implants, while the remaining cones appeared stable. All cases of cone loosening occurred in patients with Type 2B or 3 defects. The mean Knee Society score (KSS) improved significantly from 50 (0 to 94) preoperatively to 87 (72 to 94) (p < 0.001). Three intraoperative fractures with cone impaction (two femoral, one tibial) healed uneventfully.

Conclusion

Novel 3D-printed titanium cones, with a reamer-based system, yielded excellent early survivorship and few complications in patients with severe bone loss undergoing difficult revision TKA. The diversity of cone options, relative ease of preparation, and outcomes rivalling those of previous designs of cone support their continued use. Cite this article: Bone Joint J 2020;102-B(6 Supple A):107–115.
Risk factors for manipulation under anaesthesia after total knee arthroplasty
Authors: Knapp Paul , Weishuhn Luke , Pizzimenti Natalie , Markel David C.
Published: May 2020

Aims

Postoperative range of movement (ROM) is an important measure of successful and satisfying total knee arthroplasty (TKA). Reduced postoperative ROM may be evident in up to 20% of all TKAs and negatively affects satisfaction. To improve ROM, manipulation under anaesthesia (MUA) may be performed. Historically, a limited ROM preoperatively was used as the key harbinger of the postoperative ROM. However, comorbidities may also be useful in predicting postoperative stiffness. The goal was to assess preoperative comorbidities in patients undergoing TKA relative to incidence of postoperative MUA. The hope is to forecast those who may be at increased risk and determine if MUA is an effective form of treatment.

Methods

Prospectively collected data of TKAs performed at our institution’s two hospitals from August 2014 to August 2018 were evaluated for incidence of MUA. Comorbid conditions, risk factors, implant component design and fixation method (cemented vs cementless), and discharge disposition were analyzed. Overall, 3,556 TKAs met the inclusion criteria. Of those, 164 underwent MUA.

Results

Patients with increased age and body mass index (BMI) had decreased likelihood of MUA. For every one-year increase in age, the likelihood of MUA decreased by 4%. Similarly, for every one-unit increase in BMI the likelihood of MUA decreased by 6%. There were no differences in incidence of MUA between component type/design or fixation method. Current or former smokers were more likely to have no MUA. Surprisingly, patients discharged to home health service or skilled nursing facility were approximately 40% and 70% less likely than those discharged home with outpatient therapy to be in the MUA group. MUA was effective, with a mean increased ROM of 32.81° (SD 19.85°; -15° to 90°).

Conclusion

Younger, thinner patients had highest incidence of MUA. Effect of discharge disposition on rate of MUA was an important finding and may influence surgeons’ decisions. Interestingly, use of cement and component design (constraint) did not impact incidence of MUA. Level of Evidence II: Prospective cohort study. Cite this article: Bone Joint J 2020;102-B(6 Supple A):66–72.
Addressing prosthetic joint infections via gentamicin-eluting UHMWPE spacer
Authors: Gil Dmitry , Atici Ali E. , Connolly Rachel L. , Hugard Shannon , Shuvaev Sergey , Wannomae Keith K. , Oral Ebru , Muratoglu Orhun K.
Published: May 2020

Aims

We propose a state-of-the-art temporary spacer, consisting of a cobalt-chrome (CoCr) femoral component and a gentamicin-eluting ultra-high molecular weight polyethylene (UHMWPE) tibial insert, which can provide therapeutic delivery of gentamicin, while retaining excellent mechanical properties. The proposed implant is designed to replace conventional spacers made from bone cement.

Methods

Gentamicin-loaded UHMWPE was prepared using phase-separated compression moulding, and its drug elution kinetics, antibacterial, mechanical, and wear properties were compared with those of conventional gentamicin-loaded bone cement.

Results

Gentamicin-loaded UHMWPE tibial components not only eradicated planktonic Staphylococcus aureus, but also prevented colonization of both femoral and tibial components. The proposed spacer possesses far superior mechanical and wear properties when compared with conventional bone cement spacers.

Conclusion

The proposed gentamicin-eluting UHMWPE spacer can provide antibacterial efficacy comparable with currently used bone cement spacers, while overcoming their drawbacks. The novel spacer proposed here has the potential to drastically reduce complications associated with currently used bone cement spacers and substantially improve patients’ quality of life during the treatment. Cite this article: Bone Joint J 2020;102-B(6 Supple A):151–157.