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91.
Bone Health     
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92.
BACKGROUNDIn press-fit total hip arthroplasty (THA) ceramic-on-ceramic (CoC) bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene (CoPE) bearings, and can lead to wear-induced osteolysis, resulting in loosening of the implant. However, CoC bearings show disadvantages as well, such as squeaking sounds and being more fragile, which can cause ceramic head or liner fracture. Because comparative long-term studies are limited, the objective of this study was to determine the long-term difference in wear, identify potential predictive factors for wear, investigate radiological findings such as osteolysis, and evaluate clinical functioning and complications between these bearings.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up includes a documented series of elective THAs. Primary outcome was wear measured by anteroposterior (AP) radiographs. Secondary outcomes were potential predictive factors for wear, complications during follow-up, Harris hip score (HHS), and radiological findings such as presence of radiolucency, osteolysis, atrophy, and hypertrophy around the cup. Due to the absence of wear in the CoC group, stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis. HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis, adjusted for potential confounders.RESULTSA total of 17 CoPE (63.0%) and 25 CoC (73.5%) cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year (range 0.010; 0.350) and 0.000 mm/year (range 0.000; 0.005), which was significant (P < 0.001) between both groups. Wear always occurred in the cranial direction. Cup inclination was the only predictive factor for polyethylene (PE) wear. No dislocations, ceramic head, or liner fractures were seen. The HHS showed a mean change from baseline of 37.1 points (SD 18.5) in the CoPE group and 43.9 (SD 17.0) in the CoC group. This crude difference of 6.8 (range -5.2; 18.7) in favor of the CoC group was not significant (P = 0.26) and was not significant when adjusted for age, gender, and diagnosis either (P = 0.99). No significant differences in complications and radiological findings were seen between groups. CONCLUSIONCoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications, HHS, and radiological findings.  相似文献   
93.
BackgroundAcetabular fractures in the elderly frequently involve segmental quadrilateral plate injury, yet no consensus exists on how to best control the femoral head medial displacement. Quadrilateral surface plates (QSP) were developed to help buttress these challenging fractures. The study aims to 1) Determine the prevalence of segmental quadrilateral plate fractures (SQPF) in elderly patients; and 2) Assess if utilization of a QSP is associated with improved acetabulum fracture reduction and outcome.MethodsThis was a retrospective study conducted at a level-1 trauma centre. . All patients over 60-years that sustained an acetabular fracture between 2007 and 2019 were reviewed. Pre-operative pelvic radiographs and CT imaging were reviewed for 96 patients, to assess for SQPF. From the 96 patients reviewed, over one third of patients (n = 40, 41.6%) sustained a SQPF. Patients that had an acute-THA (n = 7) were excluded as were patients that underwent an ORIF but did not have a QSP or an anterior column buttress plate (n = 3). The remaining 30 formed the study’s cohort. We assessed the ability to achieve and maintain reduction in this elderly population, and compared outcomes using traditional anterior column buttress plates (ilioingual or intra-pelvic approach) versus an intra-pelvic pre-contoured buttress suprapectineal plate (QSP). Outcome measures included: fracture reduction using the Matta classification (desirable: anatomical/imperfect and poor), re-operations, conversion to THA and Oxford Hip Score (OHS) (for the preserved hips).ResultsTen patients had an ORIF with utilization of a QSP (QSP-group), and 20 had an ORIF but did not have the QSP (non-QSP-group). There was no difference in patient demographics between groups. Fracture patterns were also similar (p = 0.6). Postoperative fracture reduction was desirable (anatomical/imperfect) in 17 patients and poor in 13. Improved ability to achieve a desirable reduction was seen in the QSP-group (p = 0.02). Conversion to THA was significantly lower in patients that had a desirable fracture reduction (appropriate: 3/17; poor: 7/13). No patients in the QSP-group have required a THA to-date, compared to 10/20 patients in the non-QSP-group (p = 0.01). The mean time to THA was 1.6 ± 2.1 year. There was no difference in OHS between the two groups (34.4 ± 10.3).ConclusionElderly acetabulum fractures have a high incidence (approaching 40%) of segmental QPF. Desirable (anatomical/imperfect) fracture reduction was associated with improved outcome. The use of a QSP was associated with improved ability to achieve an appropriate reduction. A QSP should be considered as they are both reliable and reproducible with a significantly improved fracture reduction and lower conversion to THA.  相似文献   
94.
曾建伟  曹飞  陈鑫  李程 《西部医学》2021,33(8):1194-1198
目的 比较经直接前方入路(DAA)切开复位与闭合复位经皮空心螺钉内固定治疗股骨颈骨折的临床疗效。方法 回顾性分析2015年12月~2018年12月因股骨颈骨折在我院分别行切开复位(n=46)和闭合复位空心螺钉内固定(n=46)治疗的患者,统计患者基本资料,骨折Garden类型,从受伤到手术治疗时间,手术时间,术中出血量,术后Garden复位指数,术后1 d、术后3、6、12及24月患髋Harris功能评分,并统计术后骨折不愈合率及股骨头缺血坏死发生率;采用Spearman相关分析及Logistic多元回归分析,研究影响股骨颈骨折术后股骨头缺血坏死的因素。结果 切开复位组术中出血量、手术时间大于闭合复位组,但术后Garden复位指数优于闭合复位组(均P<0.05);术后6、12月切开复位组患髋Harris功能评分优于闭合复位组(P<0.05);术后24月内切开复位组患者股骨头缺血坏死率显著低于闭合复位组(P=0.01);两组骨折不愈合率无统计学差异(P=0.06)。Spearman相关分析发现,股骨颈骨折Garden分型与股骨颈骨折术后股骨头缺血坏死发生率呈显著正相关(R=0.521,P<0.001),但Logistic多元回归分析未能发现影响股骨颈骨折术后股骨头坏死发生率的相关因素。结论 DAA入路切开复位空心螺钉内固定治疗股骨颈骨折比闭合复位经皮空心螺钉内固定质量更佳,术后12月内患髋功能更好,术后24月内股骨头缺血坏死发生率更低。  相似文献   
95.
Total Hip Arthroplasty (THA) is a well-accepted treatment for established hip arthritis following acetabular fractures. If a conservatively managed or operated case progresses to non-union/mal-union failing to restore the joint integrity, it may eventually develop secondary arthritis warranting a total hip arthroplasty. Also, in recent years, acute total hip arthroplasty is gaining importance in conditions where the fracture presents with pre-existing hip arthritis, is not amenable to salvage by open reduction and internal fixation, or, a poor prognosis is anticipated following fixation.There are several surgical challenges in performing total hip arthroplasty for acetabular fractures whether acute or delayed. As a separate entity elderly patients pose a distinct challenge due to osteoporosis and need stable fixation for early weight bearing alleviating the risk of any thromboembolic event, pulmonary complications and decubitus ulcer. The aim of surgery is to restore the columns for acetabular component implantation rather than anatomic fixation. Meticulous preoperative planning with radiographs and Computed Tomography (CT) scans, adequate exposure to delineate the fracture pattern, and, availability of an array of all instruments and possible implants as backup are the key points for success. Previous implants if any should be removed only if they are in the way of cup implantation or infected. Press fit uncemented modern porous metal acetabular component with multiple screw options is the preferred implant for majority of cases. However, complex fractures may require major reconstruction with revision THA implants especially when a pelvic discontinuity is present.  相似文献   
96.
PurposeInjuries of both pelvic ring and acetabulum as rare very few articles are available in literature. There are no set protocols in defining the injury let alone defining early and definitive management strategies. This article is an attempt to encompass all available data to give us guidelines in managing these injuries.MethodsAn extensive literature review was carried out on PubMed/Medline, google scholar and Embase databases was done with the eligibility criteria of 1) Case series with a minimum of 20 cases. 2) The patient’s outcome reported. 3) Full article available. 4) Article in English. 5) Minimum Jadad score of 3. As per PRISMA guidelines the search was done and gradually filtered down to relevant articles which were 8 in number.ResultsThe incidence of these injuries range from 5 to 16%. The transverse acetabular fracture pattern is the commonest followed by associated both column fractures. There is equal propensity of Anteroposterior compression and lateral compression injuries. The injury mechanism appears to transmitted lateral force from the greater trochanter inwards with an implosion injury causing acetabular and pelvic injury as a continuum. The initial management is similar to managing pelvic ring injuries with focus on patient resuscitation, hemodynamic stabilization and temporary stabilization. The injury severity score and the mortality rates are comparable to isolated unstable pelvic ring injuries. Definitive management focuses on fixing the posterior pelvic ring first followed by the acetabular fracture and then the anterior pelvic ring. The displacement rates and outcome is worse than isolated acetabular injuries or pelvic injuries.ConclusionCombined Pelvic and acetabular injuries are complex injuries which need to be managed initially as we manage pelvic injury and later as we fix as an acetabular fracture meticulously.  相似文献   
97.
Background: Magnesium has been used as degradable fixation material for osteosynthesis, but it seems that mechanical strength is still a current issue in these fixations. The aim of this study was to evaluate the axial pull-out force of compression headless screws made of magnesium alloy during their resorption. Methods: The tests included screws made for osteosynthesis of the mandible head: 2.2 mm diameter magnesium alloy MgYREZr (42 screws) and 2.5 mm diameter polylactic-co-glycolic acid (PLGA) (42 pieces, control). The screws were resorbed in Sørensen’s buffer for 2, 4, 8, 12, and 16 weeks, and force was measured as the screw was pulled out from the polyurethane block. Results: The force needed to pull the screw out was significantly higher for MgYREZr screws than for PLGA ones (p < 0.01). Within eight weeks, the pull-out force for MgYREZr significantly decreased to one third of its initial value (p < 0.01). The dynamics of this decrease were greater than those of the pull-out force for PLGA screws (p < 0.05). After these eight weeks, the values for metal and polymer screws equalized. It seems that the described reduction of force requires taking into account when using magnesium screws. This will provide more stable resorbable metallic osteosynthesis.  相似文献   
98.
BackgroundThe coexistence of supracondylar humerus fracture and forearm fracture is a rare trauma (3–13%) and it is called floating elbow. The aim of this study is to clinically compare the treatment outcomes of the patients diagnosed with floating elbow who underwent surgical treatment and who were followed up forearm with immobilization with splint.Materials and MethodsWhen scanned retrospectively, 60 patients who were treated with the diagnosis of floating elbow due to traumatic causes and followed up for at least 1 year were included in our study. Surgical treatment was performed on 42 patients for forearm fracture. Eighteen patients followed up with immobilization with a long arm splint. The results were evaluated according to the criteria modified by Templeton and Graham, in comparison with the patient’s intact side.ResultsIn the patients whose forearms were followed up conservatively, the mean age was 5.67 ± 2.25 years, and the mean follow-up period was 62.17 ± 45.91 months. In the patients who underwent surgery for the forearm, the mean age was 8.79 ± 2.01 years, and the mean follow-up was 47.14 ± 34.25 months. Eighteen patients whose forearms followed up conservatively, 12 had excellent and good clinical results and 6 had poor and moderate clinical results. Excellent and good clinical results in 27 patients who underwent surgical treatment for their forearms, moderate and poor clinical results obtained in 15 of them. There was no significant difference between the two groups (p = 0.357).ConclusionsIn conclusion, satisfactory clinical and radiological outcomes can be obtained with immobilization of the forearm fracture with splint, if acceptable reduction can be provided for the forearm following fixation of the supracondylar humerus fracture with the K-wire for treatment of floating elbow injury.  相似文献   
99.
目的:探讨独活寄生汤对骨质疏松性椎体压缩骨折(OVCF)患者高迁移率族蛋白-1(HMGB-1)、C反应蛋白(CRP)、降钙素原(PCT)的影响。方法:选取2015年4月至2016年9月广州中医药大学第二附属医院收治的OVCF患者92例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组46例。2组均行经皮椎体后凸成形术治疗,对照组给予常规处理,观察组在此基础上加用独活寄生汤,2组均治疗2周。比较2组术后2周的骨折愈合情况、股骨颈骨密度及日本骨科协会腰痛评价表(JOA)评分,术前、术后3 d的炎性反应递质水平,术后1、3、7 d的疼痛视觉模拟评分(VAS)。结果:与术前比较,术后2周,2组伤椎前缘高度、股骨颈骨密度及JOA评分均升高,且观察组高于对照组,差异有统计学意义(P<0.05);2组伤椎楔变角及后凸Cobb角均降低,且观察组低于对照组,差异有统计学意义(P<0.05);术后3 d,2组血清TNF-α、CRP、PCT及HMGB-1水平均升高,且观察组低于对照组,差异有统计学意义(P<0.05)。与术后1 d比较,术后3、7 d,2组VAS评分均降低,且观察组低于对照组,差异有统计学意义(P<0.05)。结论:采用独活寄生汤治疗OVCF,可降低患者炎性反应递质水平,减轻疼痛,并可改善患者骨质疏松症状,促进骨折愈合,疗效显著。  相似文献   
100.
同型半胱氨酸(homocysteine,Hcy)是一种含硫氨基酸,以蛋氨酸为原料合成的,通过B族维生素,可以再循环生成蛋氨酸,或者通过转硫途径转化为半胱氨酸。通常同型半胱氨酸被认为是心脑血管的独立危险因素,现研究证实同型半胱氨酸也是骨质疏松的危险因素。目前Hcy引起骨质疏松甚至骨折的确切机制已研究出一小部分,仍有待于进一步研究。在机理上,同型半胱氨酸主要通过影响骨胶原的交联,刺激破骨细胞的形成和活性增加,及通过氧化应激产生活性氧促进成骨细胞的凋亡起作用。笔者将从同型半胱氨酸与骨密度及骨代谢指标、骨折的关系进行综述,通过提前干预Hcy的水平,预防骨折的发生,为骨质疏松症患者提供一种新的治疗方案。  相似文献   
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