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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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BackgroundThe clinical and radiographic effectiveness of 38% silver diamine fluoride (SDF) with and without potassium iodide (KI) was tested and compared with resin-modified glass ionomer cement (RMGIC) in indirect pulp capping of deep carious lesions in young permanent molars.MethodsOne hundred eight permanent first molars with deep occlusal cavitated carious lesions in 49 children aged 6 through 9 years were randomly allocated into 3 groups (n = 36 molars per group) and treated with SDF plus KI, SDF, and RMGIC. RMGIC was used as a base and a resin-based composite restoration followed. Clinical assessments for secondary caries (primary outcome), postoperative pain, tooth vitality, and restoration success and quality rates according to Modified US Public Health Service and Ryge Criteria for Direct Clinical Evaluation of Restorations were performed after 3, 6, and 12 months. Periapical radiographs were obtained at baseline, 6 months, and 12 months. Outcomes were assessed using mixed effects multilevel logistic and linear regression analyses.ResultsThere were no significant differences (P = .26) among the groups at all times for secondary caries, postoperative pain, tooth vitality, clinical abscess, radiographic signs of pulpal pathology, restorations’ marginal adaption, anatomic form, and surface roughness. There was a significant difference (P = .03) in restoration color, marginal staining, and luster. The RMGIC group outperformed the 2 SDF groups in color and luster.ConclusionsThe authors did not find differences among the groups in preventing secondary caries or pain or in maintaining pulpal health. The RMGIC group had better restoration color and luster than both SDF groups and better marginal staining than the SDF group.Practical ImplicationsThe results of this study can help guide treatment decision making regarding use of SDF and SDF plus KI as indirect pulp capping materials in deep cavitated lesions.This clinical trial was registered at ClinicalTrials.gov. The registration number is NCT04236830.  相似文献   
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BackgroundKnee osteoarthritis (KOA) is increasingly prevalent in North American society. The significant societal burden it represents makes it essential to promote and target new treatments in earlier phases of the disease. Among others, subchondroplasty is a newly documented technique using calcium phosphate injection targeting the osteochondral lesions preceding KOA, also known as Bone Marrow Lesions (BMLs). This article aimed to review the existing literature on clinical and radiological outcomes of subchondroplasty in the treatment of BMLs in KOA.MethodA systematic review was performed using PubMed, Embase, Medline and Cochrane Database of Systematic Reviews. Studies on calcium phosphate injections into BMLs for KOA and its clinical and radiological outcomes were screened and reviewed by independent evaluators.ResultsAfter screening, ten articles were included, totaling 540 patients. Follow-up ranged from 6 months to 7 years. Overall, the procedure showed significant functional and quality of life improvement, as well as pain relief, as shown by Patients-Reported Outcomes Measures (PROMs). There were very few complications reported, the most important being leakage of calcium phosphate outside the targeted site. Conversion rate to total knee arthroplasty (TKA) ranged from 14 % to 30 % at 2 years post-procedure. Long term radiological outcomes have been poorly documented.ConclusionsSubchondroplasty is a promising avenue for the treatment of KOA. However, quality evidence is still required before any real conclusions and practical management guidelines can be drawn. Prospective, randomized studies with a control group and a rigorous assessment of long-term clinical and radiological outcomes are recommended.  相似文献   
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ObjectivesOsteoclasts can sense the surface topography of materials. However, it is difficult to identify the structural factors that affect osteoclast formation and its function. Furthermore, we hypothesized that the type of osteoclast precursor cells also affects osteoclastogenesis in the materials. In this study, we investigated the effects of defined micro/nanoscale patterns on osteoclastogenesis from bone marrow cells (BMCs).MethodsVarious cyclo-olefin polymer (COP) patterns were prepared using nanoimprinting. The effects of shape, size, and height of the patterns, and the wettability of the patterned surfaces on osteoclastogenesis from BMCs were evaluated in vitro.ResultsOsteoclast formation was promoted on pillars (diameter, 1 μm or 500 nm; height, 500 nm). Notably, osteoclastogenesis from BMCs was better promoted on hydrophobic pillars than on hydrophilic pillars. In contrast, decreased osteoclast formation was observed on the nanopillars (diameter, 100 nm; height, 200 nm).ConclusionsWe demonstrated the promotion of osteoclast formation from BMCs on hydrophobic pillars with diameters of 1 μm and 500 nm. Some cellular behaviors in the patterns were dependent on the type of osteoclast precursor cells. The designed patterns are useful for designing the surface of dental implants or bone replacement materials with a controllable balance between osteoblast and osteoclast activities.  相似文献   
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目的 探讨IDEAL-IQ技术评估围绝经期女性腰椎椎体骨髓及椎旁肌脂肪含量定量分析价值。方法 选取2017年1月~2019年12月来福建医科大学附属泉州第一医院进行健康体检的围绝经期女性80例为研究对象,进行腰椎IDEAL-IQ扫描。根据绝经时间,将受检者分为未绝经、0年<绝经时间≤5年、5年<绝经时间≤10年、绝经时间>10年四组,每组各20人。采用单因素方差分析比较不同分组腰椎椎体脂肪百分比(FFv)及双侧椎旁肌脂肪百分比(FFLm、FFRm);年龄、绝经时间与FFv、FFLm、FFRm值分别进行Pearson相关分析。结果 不同围绝经期组患者FFv、FFLm、FFRm值比较,差异均有统计学差异(P<0.05)。年龄与腰椎FFv、FFLm、FFRm值均呈正相关(r=0.523、0.767、0.775;P均<0.001);绝经时间与腰椎FFv、FFLm、FFRm值均呈正相关(r=0.490、0.742、0.741;P均<0.001)。结论 IDEAL-IQ技术可定量评估围绝经期女性腰椎椎体骨髓及椎旁肌脂肪含量,对揭示绝经时间与椎体骨髓及椎旁肌脂肪含量的关系具有重要的指导价值。  相似文献   
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目的: 探讨采用大转子延长截骨钢丝固定加自体骨屑植骨进行全髋关节置换翻修的临床效果。方法: 自2010年12月至2018年12月,应用大转子延长截骨钢丝固定结合自体骨屑植骨,行全髋关节置换翻修术患者18例,其中男8例,女10例;年龄68~82(78.89±3.32)岁;初次置换术后至翻修时间9~22(16.33±2.93)年。术后定期随访记录患者截骨块愈合时间、完全负重活动时间、髋关节Harris评分及并发症等情况。结果: 纳入研究的18例患者均获得随访,时间16~38(25.78±6.65)个月。手术切口均Ⅰ期愈合。切口长度16~21(18.89±1.32) cm。手术时间105~128(115.44±6.59) min;出血量240~285(267.44±13.77) ml。截骨块愈合时间12~18(15.61±1.75)周;患者完全负重活动时间14~22(17.78±2.53)周。术前髋关节Harris评分(47.11±5.04)分,完全负重活动时髋关节Harris评分(76.39±3.85)分,末次随访时髋关节Harris评分(82.22±2.76)分,差异有统计学意义(P<0.05)。随访期间,患者均未发生患肢短缩、感染、切口愈合不良、假体松动及下沉、假体周围骨折等并发症。结论: 在全髋关节置换翻修术时,应用大转子延长截骨钢丝固定结合自体骨屑植骨,能够获得满意的临床治疗效果,但需要术者对翻修术前、术中及术后恢复等各个时期做好系统规划。  相似文献   
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目的: 观察以Bio-Oss骨粉bFGF支架联合大鼠骨髓间充质干细胞(BMSCs)植入大鼠拔牙窝后在牙槽窝愈合过程中对牙槽骨微结构的影响。方法: 取3周龄SD大鼠股骨全骨髓,自然贴壁分离BMSCs。选取36只6周龄SD大鼠,拔除上颌后牙,立即植入不同材料。按植入材料分为4组,即复合物组植入BMSCs联合Bio-Oss骨粉bFGF复合物、骨粉组植入Bio-Oss骨粉、干细胞组植入BMSCs和空白组直接对位缝合拔牙创。植入后4、12、24周,取上颌骨标本做micro-CT扫描。采用GraphPad Prism 6.0软件包对数据进行双因素方差分析。结果: 植入第4周,骨密度(BMD)、骨小梁分离度(Tb.Sp)、骨小梁厚度(Tb.Th)、各向异性值(DA)及骨小梁数(Tb.N),复合物组与骨粉组、干细胞组与空白对照组均无显著差异(P>0.05)。复合物组BMD在植入第12周显著高于骨粉组、干细胞组和空白对照组(P<0.05);植入第24周显著高于骨粉组和空白对照组(P<0.05)。复合物组Tb.Th在第12周和第24周显著高于骨粉组(P<0.05)。第4、12、24周,复合物组与骨粉组、干细胞组及空白对照组DA均无显著差异(P>0.05)。复合物组Tb.Sp在植入后第24周显著小于骨粉组、干细胞组和空白对照组,复合物组Tb.N在植入后第24周显著高于干细胞组和空白对照组(P<0.05)。结论: 大鼠同种异体BMSCs联合Bio-Oss骨粉-bFGF复合物对大鼠拔牙窝的愈合有促进作用。  相似文献   
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