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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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目的:分析比较"F"形空心钉与传统倒三角3枚平行螺钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折的临床疗效。方法:2017年1月至2020年1月收治Pauwels Ⅲ型股骨颈骨折患者38例,根据置入钉方式的不同将其分为两组,其中A组18例,采用"F"形空心钉固定,男12例,女6例,年龄37~55岁,受伤至手术时间1~3 d。B组20例,采用传统倒三角3枚平行拉力螺钉固定,男12例,女8例,年龄35~55岁,受伤至手术时间为1~3 d。比较两组患者骨折不愈合,股骨头坏死,股骨颈短缩,空心螺钉退出情况,髋关节功能Harris评分,疼痛视觉模拟评分(visual analogue scale,VAS)。结果:所有患者获得随访,时间为15~31个月。两组患者在骨折不愈合,股骨颈短缩,股骨头坏死方面差异无统计学意义(P>0.05);两组患者在螺钉退出方面差异有统计学意义(P<0.05)。两组患者术后12个月时髋关节Harris评分及VAS评分差异均无统计学差异(P>0.05)。结论:"F"形与传统倒三角3枚平行空心钉内固定治疗青壮年Pauwels Ⅲ型股骨颈骨折中短期疗效相似,但"F"形空心钉退钉率较低。  相似文献   
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PurposeOptical coherence tomography angiography (OCTA) was utilized to examine changes in ocular surface squamous neoplasia (OSSN) vascular patterns over time in individuals treated with topical medical therapy.MethodsTen individuals with OSSN diagnosed by clinical examination and high resolution (HR)-optical coherence tomography (OCT) were recruited. All individuals received topical immuno- or chemotherapy. OCTA images were obtained and analyzed at three points: presentation, mid-treatment and tumor resolution. Tumor metrics including tumor area (TA), tumor volume (TV), tumor depth (TD), and total tumor density (TTD) were calculated. Vessel area density (VAD) was also quantified within the OSSN, the subepithelium under and adjacent to the OSSN and the subepithelium of the uninvolved, contralateral eye. Vascular network changes were also subjectively evaluated.ResultsTA, TV, TD and TTD all significantly decreased with time (p < 0.001). The mean VAD within the OSSN significantly decreased (p < 0.001) between visits (presentation: 26.52 ± 6.8%, mid-treatment: 7.19 ± 5.88%, tumor resolution: 0.11 ± 0.34%). The mean subepithelial VAD under the OSSN also decreased with time (23.22 ± 11.03%, 20.99 ± 5.99% and 19.58 ± 7.08%), and after resolution the sub-tumor VAD (19.58 ± 7.08%) was comparable to the subepithelial VAD in the contralateral eye (15.47 ± 4.37%, p > 0.05). The mean VAD in the subepithelium adjacent to the OSSN increased with treatment, then decreased significantly between mid-treatment and resolution (23.26 ± 4.54, 28.30 ± 7.43% and 21.68 ± 6.10%, p = 0.009). Qualitatively, the tumor subepithelial vascular network was complex and dense but with tumor resolution appeared less tortuous and similar to the uninvolved eye.ConclusionOCTA provided insight into the pathophysiology of tumor angiogenesis, showing decreased vascular density and normalization of vascular networks associated with tumor resolution.  相似文献   
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AIM: To explore the changes in lens thickness and density with age. METHODS: A Chinese population-based retrospective study was performed. A total of 497 individuals (490 right eyes and 495 left eyes), ranging from 3 to 69 years old were included. Lens images obtained from IOL Master 700 were used to measure lens thickness and density. Piecewise regression model was chosen to illustrate the relationship of lens thickness and density with age. RESULTS: The proportion of people aged 3-18, 19-40, over 40 was 38.6%, 50.9% and 10.5% respectively. The whole lens thickness decreased with age during the first 7 years of life, kept stable from 8 to 16 years old, and then increased at the rate of about 27 µm per year. The thickness of the lens cortex and nucleus tended to decrease first and then increase with age, which was dependent on age stages. The whole lens density also decreased with age until 7 years old. The increasing rate of lens density was different in different age groups. The whole lens density increased rapidly from 7 to 22 years old and slowed down after 22 years old. Similarly, the changing tendency of lens cortical and nuclear density differed in different age phases. CONCLUSION: Both lens thickness and density are significantly associated with age, whereas they do not change linearly with age. Moreover, it is necessary to increase the population over 40 years old and conduct further research.  相似文献   
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AimsOligometastatic disease (OMD) represents a spectrum of clinical scenarios and various classification systems have been proposed. Bone-only OMD can occur in patients with advanced prostate cancer and validated decision-making tools are needed to assist patient selection for metastasis-directed therapy. The aim of the present study was to determine the prognostic utility of a classification system for OMD.Materials and methodsA retrospective review was conducted of all patients with bone-only oligometastatic prostate cancer treated with stereotactic body radiotherapy (SBRT) since November 2011. SBRT was delivered using CyberKnife® and gantry-based linear accelerator platforms. All patients were classified into oligometastatic states based on the European Society for Radiotherapy and Oncology/European Organisation for Research and Treatment of Cancer (ESTRO/EORTC) classification system. Kaplan–Meier and Cox regression analyses were carried out to determine the prognostic utility of this classification system.ResultsIn total, 105 patients with 145 osseous metastases were treated over 119 sessions. The median follow-up after SBRT was 23 months (interquartile range 10–39.8). Twelve patients had died after a median time of 31 months. The 3-year metastatic progression-free survival was 23% (95% confidence interval 13–32) and the 3-year overall survival was 88% (95% confidence interval 80–96). Patients in a metachronous oligometastatic state were 4.50 (95% confidence interval 1.19–17.10, P = 0.03) times more likely to experience metastatic progression compared with those with synchronous oligometastases, and 6.69 (95% confidence interval 1.05–42.50, P = 0.04) times more likely to experience any failure. Hazard ratio magnitudes increased for patients in a repeat oligometastatic state. The multivariate model for both metastatic progression-free survival and failure-free survival found prostate-specific antigen doubling time <4 months (P = 0.002; P = 0.05) to independently predict for progression.ConclusionThe ESTRO/EORTC classification of OMD predicts for progression in patients treated with SBRT for bone-only oligometastatic prostate cancer at our institution. Further validation in prospective series over multiple tumour sites is needed. These characterisation factors should be assessed in patients considered for metastasis-directed therapy together with established prognostic features.  相似文献   
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