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1.
BackgroundIn shoulder arthroplasty, bone resorption around the stem can lead to stem loosening and makes surgery difficult at the time of revision. Proximal bone resorption after reverse shoulder arthroplasty can cause instability because of a decrease of deltoid wrapping effect. As factors of the stem itself, such as stem coating, shape, length, and use of bone cement, may also affect bone resorption, a single-stem model should be used to compare bone resorptions between different pathologies and surgical procedures. However, to date, a few reports have compared these differences in detail using a single-stem model. Therefore, we investigated the prevalence and location of humeral bone resorption in a single-stem model.MethodsThe study included 100 shoulders that underwent anatomical total shoulder arthroplasty (TSA) or humeral head replacement (HHR) with a single uncemented humeral stem from 2008 to 2018. The patients were 31 men and 69 women. The mean age at surgery was 72.9 years (range, 41-86 years). The patients were divided into three groups: especially, 25, 61, and 14 shoulders received TSA for primary osteoarthritis without rotator cuff tears (TSA group), HHR using an anatomical head with rotator cuff repair for cuff tear arthropathy (CTA) (HHR group), and HHR using a CTA head without rotator cuff repair (CTA group), respectively. Patients were monitored for a mean of 56 months (range, 12-98 months). The location of bone resorption was divided into seven zones as follows: zone 1, greater tuberosity; zone 2, lateral diaphysis; zone 3, lateral diaphysis beyond the deltoid tuberosity; zone 4, tip of the stem; zone 5, medial diaphysis beyond the deltoid tuberosity; zone 6, medial diaphysis; and zone 7, calcar region. The degree of bone resorption was classified from grade 0 to 4.ResultsBone resorption of grade 3 or higher was significantly more frequent at the greater tuberosity in the HHR and CTA groups (P < .001 and P < .001, respectively) than that in the TSA group. Grade 4 bone resorption was significantly more frequent in the CTA than that in the TSA and HHR groups in zone 1 (P = .016 and P = .041, respectively).ConclusionThe state of attachment of the rotator cuff to the greater tuberosity might affect bone resorption at the greater tuberosity, such as the greater tuberosity after shoulder arthroplasty. In cases of shoulder arthroplasty for arthropathy with rotator cuff tear, performing rotator cuff repair might prevent bone resorption.Level of evidenceLevel IV; Prognosis Study  相似文献   
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Zumel-Marne  Angela  Kundi  Michael  Castaño-Vinyals  Gemma  Alguacil  Juan  Petridou  Eleni Th  Georgakis  Marios K.  Morales-Suárez-Varela  Maria  Sadetzki  Siegal  Piro  Sara  Nagrani  Rajini  Filippini  Graziella  Hutter  Hans-Peter  Dikshit  Rajesh  Woehrer  Adelheid  Maule  Milena  Weinmann  Tobias  Krewski  Daniel  ′t Mannetje  Andrea  Momoli  Franco  Lacour  Brigitte  Mattioli  Stefano  Spinelli  John J.  Ritvo  Paul  Remen  Thomas  Kojimahara  Noriko  Eng  Amanda  Thurston  Angela  Lim  Hyungryul  Ha  Mina  Yamaguchi  Naohito  Mohipp  Charmaine  Bouka  Evdoxia  Eastman  Chelsea  Vermeulen  Roel  Kromhout  Hans  Cardis  Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in...  相似文献   
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BACKGROUND CONTEXT

It is widely recognized that sagittal spinal alignment changes with age. However, there are presently no clear benchmarks for such values or those for the cervical spine in the general population. Quality epidemiological studies are needed to establish standards for spinal alignment deviation.

OBJECTIVES

In this study of an aged Japanese population, we employed random sampling from the basic resident registry of a rural town for subject selection to determine reference values of sagittal spinal alignment including the cervical spine.

STUDY DESIGN

Japanese resident cohort study based on a municipal registry.

PATIENT SAMPLE

A total of 413 aged people randomly sampled from the resident registry of a rural Japanese town.

OUTCOME MEASURES

All subjects underwent a whole spine lateral radiograph for measurement of sagittal spinal alignment parameters.

METHODS

Registered citizens of 50 to 89 years old were targeted for this survey. We established eight groups based on age (50s, 60s, 70s, and 80s) and gender (male and female) after random sampling from the resident registry of Obuse town in 2014. A total of 413 people (203 males and 210 females) were enrolled. Radiographic parameters of sagittal spinal alignment of the cohort were measured and analyzed. Funding for this study was provided by the Japan Orthopaedics and Traumatology Research Foundation (10,000 USD), the Japanese Orthopaedic Association (5,000 USD), the Japanese Society for Musculoskeletal Medicine (40,000 USD), and the Nakatomi Foundation (15,000 USD).

RESULTS

Global spinal alignments became more misaligned with age for both genders. Sagittal vertical axis (SVA) forward shift was significantly more frequent in 80s males and 70s females, and SVA in 80s females was a mean of 66 mm forward of that of 50s females. Cervical protrusion was markedly greater in 60s males onwards. In women, lumbar lordosis and posterior pelvic inclination were noticeable from a younger age than in men. The amount of pelvic tilt misalignment in female subjects was approximately 10 years earlier than their male counterparts.

CONCLUSIONS

This first resident cohort of Japanese individuals determined average spinal alignment parameters by age and gender. Spinal balance generally shifts forward as age increases. A forward shift in the upper cervical spine occurs first in men, whereas lumbopelvic alignment shift occurs first in women.  相似文献   
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Objective: Quadriceps dysfunction has been suggested as a complication after medial patellofemoral ligament (MPFL) reconstruction. The purpose of this study was to investigate changes in knee extensor strength before and after MPFL reconstruction.

Methods: Twenty patients who underwent MPFL reconstruction for unilateral recurrent patellar dislocation (18 females and 2 males; mean age 20.8 ± 7.6 years) were examined. The peak isometric torque at 60° and 90° of knee flexion and isokinetic knee extensor strength at speeds of 60°/s and 90°/s in operated and non-operated legs were measured using a dynamometer preoperatively and 6 months, 1 year, and 2 years postoperatively. The following parameters were evaluated: (1) body weight-adjusted muscle strength, (2) improvement index (post-/preoperative value × 100) (%), and (3) extensor strength ratio (operated/non-operated value × 100) (%).

Results: The mean knee extensor strength in both operated and non-operated legs significantly increased 2 years after surgery compared with that before surgery. At 2 years postoperatively, the improvement indexes of the isometric knee extensor strength at 60° and 90° and of the isokinetic knee extensor strength at 60°/s and 90°/s were 237%, 192%, 318%, and 186%, respectively, in the operated legs and 144%, 124%, 140%, and 140%, respectively, in the non-operated legs. At 2 years postoperatively, the mean isometric knee extensor strength ratios at 60° and 90° and the isokinetic knee extensor strength ratios at 60°/s and 180°/s were 81%, 84%, 81%, and 82%, respectively.

Conclusions: Knee extensor strength was improved in most patients after MPFL reconstruction, at least compared with that before surgery, although an approximately 20% deficit against the non-operated legs remained even 2 years after surgery.  相似文献   

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BackgroundMalnutrition measured by the geriatric nutritional risk index (GNRI) was reported to be associated with poor prognosis for patients with peripheral artery disease (PAD). However, the optimal cut-off value of preprocedural GNRI for critical limb ischemia (CLI) and intermittent claudication (IC) is unknown. We aimed to determine its optimal cut-off value for CLI or IC patients requiring endovascular revascularization.MethodsWe explored data of 2246 patients (CLI: n = 1061, IC: n = 1185) registered in the Tokyo-taMA peripheral vascular intervention research COmraDE (TOMA-CODE) registry, which prospectively enrolled consecutive PAD patients who underwent endovascular revascularization in 34 hospitals in Japan from August 2014 to August 2016. The optimal cut-off values of GNRI were assessed by the survival classification and regression tree (CART) analyses, and the survival curve analyses for major adverse cardiovascular and limb events (MACLEs) were performed for these cut-off values.ResultsIn addition to the first cut-off value of 96.2 in CLI and 85.6 in IC, the survival CART provided an additional cut-off value of 78.2 in CLI and 106.0 in IC for further risk stratification. The survival curve was significantly stratified by the GNRI-based malnutrition status in both CLI [high risk: 47.7% (51/107), moderate: 30.1% (118/392), and low: 10.2% (53/520), log–rank p < 0.001] and IC [high risk: 14.3% (7/49), moderate: 4.5% (29/646), and low: 0.5% (2/407), log–rank p < 0.001]. The multivariate Cox-proportional hazard analysis showed that a higher GNRI was significantly associated with a better outcome in both CLI [hazard ratio (HR) per 1-point increase: 0.97, 95% CI: 0.96–0.98, p < 0.001] and IC (HR: 0.94, 95% CI: 0.91–0.97, p < 0.001).ConclusionsPreprocedural nutritional status significantly stratified future events in patients with PAD. Given that the optimal cut-off value of GNRI in CLI was almost 10-points lower than that of IC, using a disease-specific cut-off value is important for risk stratification.  相似文献   
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This study aimed to establish the Japanese Cancer Genome Atlas (JCGA) using data from fresh frozen tumor tissues obtained from 5143 Japanese cancer patients, including those with colorectal cancer (31.6%), lung cancer (16.5%), gastric cancer (10.8%) and other cancers (41.1%). The results are part of a single‐center study called “High‐tech Omics‐based Patient Evaluation” or “Project HOPE” conducted at the Shizuoka Cancer Center, Japan. All DNA samples and most RNA samples were analyzed using whole‐exome sequencing, cancer gene panel sequencing, fusion gene panel sequencing and microarray gene expression profiling, and the results were annotated using an analysis pipeline termed “Shizuoka Multi‐omics Analysis Protocol” developed in‐house. Somatic driver alterations were identified in 72.2% of samples in 362 genes (average, 2.3 driver events per sample). Actionable information on drugs that is applicable in the current clinical setting was associated with 11.3% of samples. When including those drugs that are used for investigative purposes, actionable information was assigned to 55.0% of samples. Germline analysis revealed pathogenic mutations in hereditary cancer genes in 9.2% of samples, among which 12.2% were confirmed as pathogenic mutations by confirmatory test. Pathogenic mutations associated with non–cancerous hereditary diseases were detected in 0.4% of samples. Tumor mutation burden (TMB) analysis revealed 5.4% of samples as having the hypermutator phenotype (TMB ≥ 20). Clonal hematopoiesis was observed in 8.4% of samples. Thus, the JCGA dataset and the analytical procedures constitute a fundamental resource for genomic medicine for Japanese cancer patients.  相似文献   
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