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61.
ObjectivesTo compare the biomechanical performance of proximal femoral nail anti‐rotation (PFNA), the “upside‐down” less invasive plating system (LISS), and proximal femoral locking plate (PFLP) in fixing different fracture models of subtrochanteric fractures.MethodsThirty composite femurs were divided into three equal groups (PFNA, PFLP, and reverse LISS). The implant‐femur constructs were tested under axial compression load (0–1400 N) from models I to IV, which represented the Seinsheimer type I subtrochanteric fracture, type IIIa subtrochanteric fracture with the posteromedial fragment reduced; type IIIa subtrochanteric fracture with the posteromedial fragment lost; and type IV subtrochanteric fracture, respectively. Axial stiffness was analyzed for each group. Each group was then divided into two subgroups, one of which underwent torsional and axial compression failure testing, while the other subgroup underwent axial compression fatigue testing. The torsional stiffness, failure load, and cycles to failure were analyzed.ResultsPFNA had the highest axial stiffness (F = 761.265, p < 0.0001) and failure load (F = 48.801, p < 0.0001) in model IV. The axial stiffness and failure load of the PFLP were significantly higher than those of the LISS (p < 0.0001, p = 0.001). However, no significant difference in axial stiffness was found between models I to III (model I: F = 2.439, p = 0.106; model II: F = 2.745, p = 0.082; model III: F = 0.852, p = 0.438) or torsional stiffness in model IV (F = 1.784, p = 0.187). In fatigue testing, PFNA did not suffer from construct failure after 90,000 cycles of axial compression. PFLP and LISS were damaged within 14,000 cycles, although LISS withstood more cycles than PFLP (t = 3.328, p = 0.01).ConclusionThe axial stiffness of the three implants was similar in models I to III. The biomechanical properties of PFNA were the best of the three implants in terms of axial stiffness, failure load, and fatigue testing cycles in model IV. The axial stiffness and failure load of the PFLP were better than those of the reverse LISS, but PFLP had fewer cycles in the fatigue tests than the reverse LISS.  相似文献   
62.
ObjectivesIn geriatric acetabular fractures, the quadrilateral surface (QLS) was frequently involved in acetabular fracture patterns and accompanied by medial displacement. It was important to buttress the medial displaced QLS and reconstruct the congruity of the affected acetabulum. To evaluate the clinical effectiveness of the novel infra‐pectineal quadrilateral surface buttress plates for the treatment of geriatric acetabular fractures.MethodsTwenty‐three geriatric patients who were treated for acetabular fractures involving QLS with the novel infra‐pectineal buttress plates (NIBP) through a single supra‐ilioinguinal approach between January 2015 and June 2019 were retrospectively analyzed; all patients received at least 1 year''s follow‐up. All patients were aged ≥60 years old and including 18 males and five females. Radiologic and clinical outcomes of patients involved in the study were collated and analyzed according to the Matta scoring system and the Merle D''Aubigné–Postel scoring system. The functional recovery scoring was compared using q‐test.ResultsAll 23 consecutive patients had relatively satisfactory clinical treatment effectiveness. Average ages, length of incision, operation time, and intraoperative blood loss were 69.8 ± 6.1 years, 12.1 ± 2.6 cm, 166.5 ± 43.5 min, and 500 (500,700) ml, respectively. According to the Matta scoring system, 14 cases of reduction were graded as excellent, five as good, and four as fair. At the last follow‐up, the clinical outcome evaluation was excellent in 13 cases, good in seven cases, and poor in three cases with the use of the Merle D''Aubigné–Postel scoring system. The difference of modified Merle D''Aubigne‐Postel score at 3 months, 6 months and last follow up was statistically significant (F = 21.56, p < 0.05). Postoperative lateral femoral cutaneous nerve injury occurred in three patients and heterotopic ossification occurred in one patient.ConclusionsFor the treatment of geriatric acetabular fractures, the NIBP could provide stable and effective fixation to the QLS involved acetabular fractures, and related satisfactory clinical results with few complications were noted.  相似文献   
63.
BackgroundTalus fractures are rare in children but can lead to severe outcomes if untreated. The Ilizarov external fixator has been used in the treatment of a variety of lower extremity pathologies. The purpose of this study was to investigate the clinical outcomes of talus body fractures treated with the Ilizarov external fixator.Case PresentationFour male pediatric patients (age range, 5–11 years) with talus body fractures who were treated by open reduction and internal fixation combined with Ilizarov external fixator between November 2015 and April 2016 were reviewed. Mean follow‐up period was 4 years (range, 4–5). Clinical outcome was evaluated using the clinical rating scale of the American Orthopaedic Foot and Ankle Society (AOFAS). All four patients achieved good to excellent results at the last follow‐up. None of the patients developed avascular necrosis. One patient developed automatic fusion of tibiotalar joint.ConclusionUse of the Ilizarov external fixator to gain early range of motion is a valuable option for treatment of talus body fractures in children.  相似文献   
64.
目的:探讨改良口外须颅颌固定治疗上颌骨骨折的临床效果。方法:对35例上颌骨Le FortⅡ、Ⅲ型骨折患者,先行闭合复位,恢复受伤前的咬合关系,再行改良口外须颅颌固定牵引3~4周。结果:35例Le FortⅡ、Ⅲ型骨折患者总有效率达94.2%。结论:改良口外须颅颌固定牵引治疗上颌骨骨折是一种简单易行、可靠的方法。  相似文献   
65.
股骨髁支持钢板治疗股骨远端C3型骨折   总被引:1,自引:1,他引:0  
2001~2005年,我院应用股骨髁支持钢板治疗25例C3型股骨远端骨折患者,取得了良好疗效。  相似文献   
66.
1996~2005年,笔者采用克氏针横形固定治疗小儿胫骨开放性斜形骨折20例,效果良好. 1 材料与方法 1.1 病例资料本组20例,男12例,女8例,年龄4~13岁.均为新鲜开放性胫腓骨骨折,但胫骨折端为斜形,内外移位骨折16例,前后移位骨折4例.  相似文献   
67.
锁骨骨折是临床较常见的骨折之一.近几年应用镍钛记忆合金环抱器治疗锁骨骨折的报道较多,但报道其优点较多,很少谈其缺点及不足.2005年1月~2007年1月,我科收治24例锁骨骨折患者,采用镍钛记忆合金环抱器治疗,笔者对其利弊进行分析如下.  相似文献   
68.
距骨颈骨折的手术治疗   总被引:4,自引:1,他引:3  
目的探讨距骨颈骨折的手术治疗及并发症防治。方法回顾2000年至2004年手术治疗的距骨颈骨折12例,总结其手术入路、内固定方法及术后处理。结果所有患者均在术后12~14d伤口拆线出院,无伤口感染、不愈合或皮肤坏死发生。12例患者中有10例获得随访,随访7个月至5年,平均3年4个月。按Hawkins标准优2例、良7例、中1例,创伤性骨关节炎4例,距骨无菌性坏死2例。结论对于复位不理想的距骨颈骨折应积极行切开复位内固定,强调骨折的解剖复位,避免术后过早负重,降低术后并发症的发生几率。  相似文献   
69.
目的分析普通钢板内固定治疗胫骨骨折术后骨不连的发生原因与治疗对策。方法自1998年7月~2005年12月共收治胫骨骨折患者182例。全部采用普通钢板内固定治疗。术后平均随访14个月(12~18个月)。结果182例中有175例达到临床愈合标准,并已拆除钢板,未发生骨髓炎、再骨折等并发症。经X线片检查,骨折均为骨性愈合,骨折临床愈合时间12~16周,平均14周。7例未达到临床愈合标准,发生率为3.85%。患者同时合并有腓骨骨折,主要并发症为术后骨不连。结论普通钢板内固定目前仍是基层医院治疗胫骨骨折的有效方法,只要严格掌握适应症,熟练掌握操作规程,可以减少并发症,提高疗效。  相似文献   
70.
对环境施磷增加田菁[Sesbania cannabina(Retz.)pers.]结瘤固氮的作用是有限度的,受环境供磷水平的制约。 在广州石牌地区花岗岩发育赤红壤中,田菁以磷增氮的土壤有效磷临界水平(ppm P)为25.6(0.1 N HCL法)。 在无氮培养液中,秋植和春植田菁以磷增氮的供磷临界水平(毫摩尔P)分别为0.78和0.48,植株体内含磷量的临界水平(P%)分别为0.213和0.157。该临界供磷水平与含磷量有受季节性影响的倾向。介质的高磷水平还会引起田菁固氮量的下降。 在低磷的介质中,增磷对田菁根瘤的形成,发育和固氮酶活性有明显的促进作用。在磷供应达到一定水平后,继续增磷的促进作用不显著。未发现高磷供应对田菁的根瘤数有不良影响,但对其根瘤干重、特别是固氮酶活性有抑制作用。  相似文献   
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