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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   
2.
The impact of vaccination and new SARS-CoV-2 variants on peri-operative outcomes is unclear. We aimed to update previously published consensus recommendations on timing of elective surgery after SARS-CoV-2 infection to assist policymakers, administrative staff, clinicians and patients. The guidance remains that patients should avoid elective surgery within 7 weeks of infection, unless the benefits of doing so exceed the risk of waiting. We recommend individualised multidisciplinary risk assessment for patients requiring elective surgery within 7 weeks of SARS-CoV-2 infection. This should include baseline mortality risk calculation and assessment of risk modifiers (patient factors; SARS-CoV-2 infection; surgical factors). Asymptomatic SARS-CoV-2 infection with previous variants increased peri-operative mortality risk three-fold throughout the 6 weeks after infection, and assumptions that asymptomatic or mildly symptomatic omicron SARS-CoV-2 infection does not add risk are currently unfounded. Patients with persistent symptoms and those with moderate-to-severe COVID-19 may require a longer delay than 7 weeks. Elective surgery should not take place within 10 days of diagnosis of SARS-CoV-2 infection, predominantly because the patient may be infectious, which is a risk to surgical pathways, staff and other patients. We now emphasise that timing of surgery should include the assessment of baseline and increased risk, optimising vaccination and functional status, and shared decision-making. While these recommendations focus on the omicron variant and current evidence, the principles may also be of relevance to future variants. As further data emerge, these recommendations may be revised.  相似文献   
3.
《Clinical breast cancer》2020,20(5):390-394
BackgroundBreast cancer patients with triple-negative or human epidermal growth factor receptor 2 (HER2)-overexpressing phenotypes are recommended to receive chemotherapy for primary tumors greater than 1 cm regardless of nodal status. Neoadjuvant chemotherapy may eradicate subclinical nodal metastases and reduce the extent of axillary surgery performed.Patients and MethodsA query of the National Cancer Database Participant User File was performed for new cases of female breast cancer from 2012 to 2015. Inclusion criteria were clinical N0 status, receipt of chemotherapy, and receipt of axillary surgery. Exclusions included hormone-positive/HER2-negative tumors and/or distant metastatic disease. Subjects were divided into groups by receipt of neoadjuvant or adjuvant chemotherapy. The primary end point was the extent of axillary surgery, defined as sentinel lymph node biopsy alone or axillary lymph node dissection (ALND). Subgroup analyses were performed on the basis of tumor phenotype and surgery of the primary site.ResultsA total of 66,771 female patients were included, 15,967 of whom underwent neoadjuvant chemotherapy. ALND rates were higher in patients who received adjuvant chemotherapy (30.6% vs. 28.8%, P < .001). Among tumor phenotypes, the extent of axillary surgery was reduced most significantly for hormone-negative, HER2-positive disease (30.0% vs. 25.8%, P < .001). ALND rates were more substantially reduced for patients who underwent mastectomy (41.3% vs. 36.1%, P < .001) compared to partial mastectomy (21.8% vs. 20.1%, P = .002). Adjuvant chemotherapy was an independent predictor of ALND (odds ratio, 1.26; 95% confidence interval, 1.19-1.33).ConclusionNeoadjuvant chemotherapy reduces the extent of axillary surgery in clinically node-negative, nonluminal breast cancers.  相似文献   
4.
新型冠状病毒肺炎是感受新型冠状病毒所致,属于中医学“疫病”的范畴,其病因为吴又可提出的“异气”,与六淫不同,具有生物学属性;侵袭人体主要造成气阴损伤,气化失常,湿饮停聚;治疗当以“逐邪为第一要义”,恢复机体平衡状态。  相似文献   
5.
《中国现代医生》2020,58(30):61-64
目的探讨不同时期颅骨修补术对颅脑损伤患者术后神经功能的影响。方法 选取我院在2013 年1 月~2020 年1 月收治的60 例颅脑损伤患者为研究对象,随机分为早期组(n=30)与晚期组(n=30),分别予以早期、晚期颅骨修补术;比较两组患者的治疗效果、神经功能、日常生活活动能力及并发症发生情况。结果 (1)早期组优良率为86.67%,明显高于晚期组的60.00%(P<0.05)。(2)早期组与晚期组术前NIHSS 评分比较,差异无统计学意义(P>0.05),两组术后NIHSS 评分均明显低于术前,且早期组明显低于晚期组(P<0.05)。(3)早期组与晚期组术前Barthel 指数比较,差异无统计学意义(P>0.05),两组术后Barthel 指数均明显高于术前,且早期组明显高于晚期组(P<0.05)。(4)早期组并发症总发生率为10.00%,明显低于晚期组的23.33%(P<0.05)。结论 对颅脑损伤患者早期予以颅骨修补术治疗可获得更好的治疗效果,能够明显改善患者神经功能,提高日常生活活动能力,减少并发症的发生。  相似文献   
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目的:测定南方红豆杉不同组织器官紫杉烷类物质的含量,优选出最佳采收部位,为其开发利用提供依据。方法:分别采集南方红豆杉植株主干树皮、侧皮、根皮、须根、茎、叶六个组织器官材料,运用HPLC法检测紫杉烷类物质含量,确定其最佳利用组织器官。结果:南方红豆杉四种紫杉烷类在组织中的分布明显地受组织分化的影响,其中10-脱乙酰巴卡亭Ⅲ在叶中最多,7-表-10-去乙酰基紫杉醇在侧皮中最多,紫杉醇、三尖杉宁碱则在根中最多。结论:叶是合成紫杉醇前体物质的主要器官,而皮与根则是合成及积累紫杉醇的主要组织器官。  相似文献   
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