两种前交叉韧带重建MRI测量移植物位置比较

[目的]探讨磁共振成像(MRI)测量前内侧入路(anteromedial, AM)法和经胫骨隧道(transtibial, TT)法建立股骨隧道重建前交叉韧带(anterior cruciate ligament, ACL)移植物位置的差异。[方法]回顾性分析2017年1月—2018年12月本院收治的62例患者,其中32例采用AM法,30例采用TT法。行MRI检查,测量冠状面移植物股骨止点与12点位的夹角(α角)、矢状面移植物轴线与Blumensaat线夹角(β角)、矢状面股骨隧道后壁厚度(AB),以及矢状面移植物与胫骨平台面夹角(θ角)、矢状面胫骨止点位置(CE/CD)、冠状面移植物与胫骨平台面夹角(γ角)和冠状面胫骨止点位置(GF/GH)。[结果]股骨侧,两组在α角、β角和AB的差异均无统计学意义(P0.05);末次检查时两组的α角、β角和AB与首次检查的差异均无统计学意义(P0.05)。胫骨侧,AM组θ角显著小于TT组(P0.05);但两组间在γ角、CE/CD和GF/GH的差异均无统计学意义(P0.05);末次检查时两组的θ角均较首次检查显著减小(P0.05),而γ角、CE/CD及GF/GH的差异无统计学意义(P0.05)。[结论]本研究表明在矢状面上,TT法移植物较AM法更为垂直;随着术后时间延长,两种术式移植物的矢状面角度会减小。     

国人正常股骨CT测量与假体设计的相关研究

目的：本文报告１１０例国人正常股骨ＣＴ测量与假体设计的相关研究。方法：双下肢取中立位，行股骨横断面和全长ＣＴ扫描。由ＣＴ软件测量股骨长度，股骨头直径，头位置，头心－干轴梗距，颈干角，转子部髓腔最大冠、矢状径１６项参数。结果：所得数据行统计学处理，得出各参数分布规律和其间的相关性，并与白种人相应参数比较。各髓腔径小于白种人的参数值，髓腔冠状径、头心－干轴距、股骨头位置与白种人的参数比较，差异有非常显     

OrthoPilot计算机红外线导航系统在膝内翻畸形全膝关节置换术中的应用

目的探讨OrthoPilot计算机红外线导航系统在合并膝内翻畸形膝关节骨性关节炎全膝关节置换术中应用的效果。方法纳入自2018-01—2019-01行单侧全膝关节置换术治疗的40例合并膝内翻畸形的膝关节骨性关节炎,20例采用OrthoPilot计算机红外线导航系统辅助手术(导航组),20例采用常规髓内定位技术(常规组)。结果 40例均获得随访,随访时间平均24(12～36)个月。导航组手术时间较常规组短,术中出血量较常规组少,术后12个月膝关节遗忘程度评分高于常规组,差异有统计学意义(P0.05)。术后1个月摄X线片测量髋-膝-踝角、冠状面股骨组件角、冠状面胫骨组件角、矢状面股骨组件角、矢状面胫骨组件角,与理想状态下各角度的偏移值均4°,且导航组上述参数偏移值小于常规组,差异有统计学意义(P0.05)。结论计算机红外线导航系统辅助全膝关节置换术治疗合并膝内翻畸形膝关节骨性关节炎的短期临床疗效可靠,患者下肢力线矫正更满意,假体组件安装的位置更加精确,膝关节功能恢复良好。     

初次全髋关节置换术中后外侧入路与直接前方入路对解剖柄位置的影响

目的探究初次全髋关节置换术中后外侧入路与直接前方入路对解剖柄位置的影响及对股骨前倾角影响因素的分析。方法纳入自2015年6月至2020年6月在我院由同一名医师使用解剖柄进行初次全髋关节置换的108例共114个髋关节。患髋屈曲活动范围60°,下肢需延长2 cm,身体质量指数(body mass index,BMI)30 kg/m~2,患者要求后外侧入路(posterolateral approach,PLA)者采用PLA手术入路,其余采用前方入路(direct anterior approach,DAA)。DAA组共44髋,男性24髋,女性20髋;平均年龄(60.1±12.1)岁;PLA组共70髋,男性38髋,女性32髋;平均年龄(59.8±11.4)岁。患者仰卧位,CT扫描患侧(髂前上棘至胫骨结节),重建股骨三维图形,测量股骨假体柄在矢状面、冠状面及水平面的位置、前倾角,距小转子截骨距离及股骨头前后距离。结果术前DAA组股骨前倾角(23.2±10.4)°,PLA组股骨前倾角(27.7±10.9)°,两组比较差异有统计学意义(P=0.003)。术后两组股骨前倾角分别为(28.5±11.5)°、(30.7±9.2)°,差异无统计学意义(P=0.141)。术后两组前倾角变化比较,差异有统计学意义(P=0.043);两组假体柄矢状面夹角和矢状面夹角变化比较,差异均有统计学意义(P=0.008,P=0.003)。术前前倾角与术后前倾角相关,差异有统计学意义(P=0.001);DAA入路屈曲植入假体柄个数与PLA入路组相比,差异有统计学意义(P=0.043);股骨头前后距离变化在两种入路中比较差异无统计学意义(P=0.882)。结论术前股骨前倾角是影响术后前倾角变化的因素,手术入路不影响术后前倾角及股骨头前后距离的变化,而手术入路对假体柄在矢状面的位置有影响。     

术者利手侧别对初次人工全膝关节置换术中假体位置影响的研究

目的探讨术者利手侧别对初次人工全膝关节置换术(total knee arthroplasty,TKA)中假体放置位置的影响。方法将2016年12月—2018年12月由同一右利手术者完成的86例(100膝)初次TKA患者纳入研究,单膝72例、双膝14例。根据术者术中操作位置不同分为优势组(右侧)及非优势组(左侧),两组各50膝。两组患者性别、年龄、体质量指数、病程、临床诊断及术前美国特种外科医院(HSS)评分等一般资料比较,差异均无统计学意义(P0.05),具有可比性。记录两组手术时间及并发症发生情况,采用HSS评分评价膝关节功能;于术前及术后2周下肢全长X线片测量髋-膝-踝角(hip-knee-ankle angle,HKA)、股骨远端外侧角(mechanical lateral distal femoral angle,mLDFA)、胫骨近端内侧角(mechanical medial proximal tibial angle,mMPTA),评价假体冠状位位置;于术后3个月膝关节侧位X线片测量股骨远端后方角(posterior distal femoral angle,PDFA)、胫骨近端后方角(posterior proximal tibial angle,PPTA),评价矢状位假体位置。结果两组手术时间差异无统计学意义(t=-1.128,P=0.262)。优势组1例术后出现胫后动脉血栓形成,优势组和非优势组各1例出现切口愈合不良,其余患者无并发症发生。两组患者均获随访,随访时间12～34个月,平均22.0个月。末次随访时,优势组HSS评分为(87.2±4.3)分,非优势组为(86.8±5.0)分,组间比较差异无统计学意义(t=0.471,P=0.639)。X线片复查示,两组随访期间均未发生假体周围感染、无菌性松动、假体周围骨折等并发症。手术前后两组HKA、mLDFA、mMPTA差异均无统计学意义(P0.05)。术后3个月两组PDFA及矢状位股骨假体位置不良发生率比较,差异有统计学意义(P0.05);但PPTA、股骨假体力线达中立位比例以及股骨假体过屈、股骨前方切迹发生率比较,差异均无统计学意义(P0.05)。结论术者利手侧别是影响初次TKA时股骨假体矢状位位置因素之一,非优势侧手术时矢状位股骨假体位置不良发生率增高。     

青少年特发性脊柱侧凸后路矫形后远端交界区变化

目的:探讨青少年特发性脊柱侧凸(AIS)患者后路矫形术后远端交界区(LIV+2)在冠状面、矢状面和轴位上的变化。方法:2005年6月～2007年6月手术治疗AIS患者32例,男6例,女26例,年龄10～19岁,平均14.4岁。按PUMC分型,Ⅰc1例,Ⅱa4例,Ⅱb19例,Ⅱb21例,Ⅱc11例,Ⅱc35例,Ⅱd15例,Ⅲa5例,Ⅲb1例。均采用后路全节段椎弓根螺钉系统矫形固定,其中远端融合椎(LIV)与稳定椎(SV)为同一椎体(A组)15例,LIV与SV非同一椎体(B组)17例。术前和末次随访时摄站立位全脊柱正侧位X线片,测量冠状面上躯干偏移(TS),LIV的倾斜度(LIVT),LIV尾侧椎间盘开角(LIVA),冠状面和矢状面上远端交界区的Cobb角和椎体的旋转度(LIV+1VR和LIV+2VR)。结果:随访24～36个月,平均29个月。两组末次随访时的TS与术前比较均无显著性差异(P0.05)。A组LIVT由术前20.2°±5.9°下降到末次随访时的4.7°±3.8°(P0.001),B组由17.2°±5.5°下降到4.4°±2.7°(P0.001);A组术前和末次随访时LIVA分别为7.5°±4.7°和3.9°±3.1°(P=0.056);B组分别为4.5°±3.4°和5.4°±3.2°(P=0.492);Pearson′s相关分析显示两组远端融合椎倾斜度变化和其尾侧椎间盘开角变化之间相关性不显著(A组r=-0.067,P=0.813;B组r=0.362,P=0.154)。A组远端交界区(LIV+2)冠状面上Cobb角由术前20.5°±9.6°矫正至末次随访时9.4°±7.3°(P0.001);B组由13.8°±6.7°矫正至8.1°±4.7°(P=0.013);A、B组末次随访时远端交界区矢状面上Cobb角与术前比较均无显著性差异(分别为P=0.464,P=0.598);Pearson′s相关分析显示A组末次随访时矢状面Cobb角和术前矢状面Cobb角之间相关性不显著(r=0.076,P=0.788),B组的相关性显著(r=0.803,P0.001)。两组末次随访时LIV+1VR和LIV+2VR与术前比较均无显著性差异(P0.05)。结论:AIS患者应用后路全节段椎弓根螺钉系统矫正后远端交界区在冠状面上矫形明显,矢状面和轴位上矫形不明显,且远端融合椎倾斜度减小。     

成人正常股骨解剖测量及其在膝关节置换的临床意义

[目的]为膝关节置换准确截骨和获得良好的下肢力线，对中原地区成人股骨干进行相关测量。[方法]（1）选取47根成人正常股骨标本，拍摄正、侧位数码照片，进行定点、划线、测量五角。（2）实体上确定股骨髓内定位杆进针点的位置：[结果]（1）各角度值反映了股骨远端在冠状位和矢状位的解剖形态。（2）进针点与股骨滑车中心水平距离平均为6．21mm，与后交叉韧带止点前缘距离平均为6．70mm。[结论]（1）股骨远端1／3段与股骨近端1／3段向外侧、前侧成角，且前倾角度大于外翻角度。所以股骨远端在决定股骨髓内定位杆的位置时，冠状面上的力线对位和矢状面上的对位均很重要。（2）全膝关节置换术中确定进针点可参考股骨滑车中心和股骨髁后交叉韧带止点的位置。     

Ⅰ类和Ⅱ类矢状骨面型成年男性舌骨位置差异的研究

目的:比较Ⅰ类和Ⅱ类矢状骨面型成年男性舌骨位置的差异,探讨舌骨位置与矢状向骨面型的关系。方法:选择垂直向均角型的Ⅰ类和Ⅱ类矢状骨面型成年男性各30例,拍摄头颅侧位定位片,对其舌骨位置相关指标进行测量分析。结果:Ⅱ类矢状骨面型成年男性舌骨水平向测量指标除AH-Or外均小于Ⅰ类矢状骨面组,差异有统计学意义(P0.05),但舌骨垂直向各测量值两组差异均无统计学意义(P0.05)。结论:垂直向均角型的Ⅰ类和Ⅱ类矢状骨面型成年男性舌骨位置存在差异,Ⅱ类矢状骨面型成年男性舌骨位置比较居后位。     

中国人髋臼下部螺钉三维位置研究

目的本研究针对中国人骨盆三维形态进行髋臼下部螺钉的位置研究。方法选择2013—2018年香港大学深圳医院因非骨盆疾病需要进行骨盆CT扫描的研究对象,其中男性22例(44髋),平均年龄(33.5±5.1)岁;女性33例(66髋),平均年龄(35.1±5.6)岁。将CT图像进行3D重建,标记髋臼下部骨皮质及髓腔,自动生成最贴合髓腔的圆柱体,此圆柱体代表髋臼下部螺钉需通过的最狭窄处,延长圆柱体,穿出骨盆入口处皮质,圆柱体的轴与骨盆皮质交点代表钉道入口,此交点用于测量钉道入口位置,圆柱体的轴用于测量钉道角度和钉道长度。标记骨盆入口平面和骨盆冠状面、矢状面。测量钉道在骨内的长度。测量髂前上棘到耻骨联合的距离A,耻骨联合到钉道入口的距离B,计算A/B。测量骨盆入口平面上钉道与矢状面的夹角,矢状面上钉道与骨盆入口平面的夹角,冠状面上钉道与矢状面的夹角,矢状面上钉道与冠状面的夹角。比较男性与女性钉道位置的差异,以P0.05为差异有统计学意义。结果 27%的男性研究对象不存在钉道,36%的女性研究对象不存在钉道。其余男性的钉道长度为(89.0±10.1)mm,女性为(83.6±8.7)mm,两者比较差异有统计学意义(P0.05)。男性的钉道直径(4.3±1.0)mm,女性为(3.4±0.8)mm,两者比较差异有统计学意义(P0.05)。男性骨盆入口平面上钉道与矢状面的夹角为(5.1±2.1)°,女性为(18.0±7.6)°,两者比较差异有统计学意义(P0.05)。男性矢状面上钉道与骨盆入口平面的夹角为(75.5±12.5)°,女性为(70.6±11.5)°,两者比较差异无统计学意义(P0.05)。男性冠状面上钉道与矢状面的夹角为(11.0±6.1)°,女性为(18.1±10.1)°,两者比较差异有统计学意义(P0.05)。男性矢状面上钉道与冠状面的夹角为(60.0±13.8)°,女性为(57.1±12.9)°,两者比较差异无统计学意义(P0.05)。男性A/B为(2.5±0.3),女性为(2.6±0.3),两者比较差异无统计学意义(P0.05)。结论男性更有可能存在髋臼下部螺钉的钉道,男性钉道长度和直径大于女性;男性骨盆入口平面上和冠状面上钉道与矢状面的夹角均小于女性,提示男性钉道更加平行于矢状面。与西方人相比,中国人存在钉道的人群占比较小,钉道的直径更小而长度更长。中国人钉道入口更加靠近耻骨联合,而西方人钉道更加平行于矢状面。     

退行性脊柱侧凸患者冠状面和矢状面影像学参数分析

目的 :分析退行性脊柱侧凸(DS)患者的影像学特征,探讨与DS患者冠状面影像学参数与矢状面平衡之间的关系。方法:回顾性分析99例DS患者的人口统计学资料和影像学资料,包括年龄、性别、冠状位Cobb角、顶椎椎体/椎间盘的位置、侧凸的方向、顶椎旋转度、侧凸节段、胸椎后凸角(TK)、腰椎前凸角(LL)、胸腰椎后凸角(TL)、骶骨角(SS)、骨盆倾斜角(PT)、骨盆入射角(PI)、矢状位垂直轴(SVA)和PI-LL。根据矢状面平衡情况将患者分为两组:失平衡组(A组),SVA5cm;平衡组(B组),SVA≤5cm,比较两组患者的人口学和影像学参数。结果:99例患者中女83例,男16例;年龄41~92岁(中位数为67岁);冠状位Cobb角10°~75°(中位数为23°);侧凸长度3~7个椎体(中位数为5个椎体)。顶椎最常见的位置在L2/3(81%),顶椎椎体旋转程度的中位数为Ⅱ度(Ⅰ~Ⅲ度)。冠状位Cobb角和侧凸节段相关(r=0.23,P0.005),和顶椎旋转亦相关(r=0.53,P0.005)。A组33例,B组66例;两组间年龄、LL、PT、冠状位Cobb角、顶椎旋转度和PI-LL均有显著性差异(P0.05),两组间性别、TK、TL、SS和PI无显著性差异(P0.05)。结论:DS患者冠状位Cobb角与侧凸节段和顶椎旋转间有相关关系;矢状位平衡和失衡患者的年龄、冠状位Cobb角、LL、PT和PI-LL均不同。     

Definition of a Novel Proximal Femur Classification in the Sagittal Plane According to the Femur Morphometric Analysis

BackgroundStudies on prosthesis positioning and implant design in total hip arthroplasty (THA) have generally focused on the anatomy of the proximal femur in the coronal plane. The aim of this study was to investigate the proximal femur morphology in the sagittal plane to provide better positioning of the femoral component in THA and contribute to the determination of proximal femur morphology through possible outcomes that can be shown also by considering the sagittal plane in the selection and design of the femoral component.MethodsComputerized tomography scans were obtained from 270 femoral bones belonging to adult skeletons, followed by 3D reconstruction using Leonardo Dr/Dsa Va30a software (Siemens, Erlangen, Germany) and measurements. Canal widths were measured in the coronal and sagittal planes at the lesser trochanter (LT) level, at 20 millimeters proximal to the LT(LT+20) and at various levels distal to the lesser trochanter in 25 mm jumps up to 200 mm from the lesser trochanter.ResultsThe average width was wider at the level of the lesser trochanter and all points distal to it in the sagittal plane compared to the coronal plane except LT?200 mm. At each levels from LT?25 to LT?175, the differences were statistically significant (P < .05). The ratio of the femoral width at the lesser trochanter level to the width 50 mm distal to the LT was stated as the most prevalent one, and a novel classification in the sagittal plane was developed in accordance with these findings.ConclusionA novel and simple classification in the sagittal plane was developed based on the findings of this study, and this classification may improve the accuracy, validity, and reliability of femoral stem fixation in total hip arthroplasty.     

Proximal Femur Geometry To Detect and Distinguish Femoral Neck Fractures from Trochanteric Fractures in Postmenopausal Women

Some proximal femur geometry (PFG) parameters, measured by dual-energy X-ray absorptiometry (DXA), have been reported to discriminate subjects with hip fracture. Relatively few studies have tested their ability to discriminate femoral neck fractures from those of the trochanter. To this end we performed a cross-sectional study in a population of 547 menopausal women over 69 years of age with femoral neck fractures (n= 88), trochanteric fractures (n= 93) or controls (n= 366). Hip axis length (HAL), neck–shaft angle (NSA), femoral neck diameter (FND) and femoral shaft diameter (FSD) were measured by DXA, as well as the bone mineral density (BMD) of the nonfractured hip at the femoral neck, trochanter and Ward’s triangle. In fractured subjects, BMD was lower at each measurement site. HAL was longer and NSA wider in those with femoral neck fractures. With logistic regression the age-adjusted odds ratio (OR) for a 1 standard deviation (SD) decrease in BMD was significantly associated at each measurement site with femoral neck fracture (femoral neck BMD: OR 1.9, 95% confidence interval (95% CI): 1.4–2.5; trochanter BMD: OR 1.6, 95% CI 1.2–2.0; Ward’s triangle BMD: OR 1.7, 95% CI 1.3–2.2) and trochanteric fracture (femoral neck BMD: OR 2.6, 95% CI 1.9–3.6; trochanter BMD: OR 3.0, 95% CI 2.2–4.1; Ward’s triangle BMD: OR 1.8, 95% CI 1.4–2.3). Age-adjusted OR for 1 SD increases in NSA (OR 2.2, 95% CI 1.7–2.8) and HAL (OR 1.3, 95% CI 1.1–1.6) was significantly associated with the fracture risk only for femoral neck fracture. In the best predictive model the strongest predictors were site-matched BMD for both fracture types and NSA for neck fracture. Trochanteric BMD had the greatest area (0.78, standard error (SE) 0.02) under the receiver operating characteristic curve in trochanteric fractures, whereas for NSA (0.72, SE 0.03) this area was greatest in femoral neck fractures. These results confirm the association of BMD with proximal femur fracture and support the evidence that PFG plays a significant role only in neck fracture prediction, since NSA is the best predictive parameter among those tested. Received: 24 April 2001 / Accepted: 1 August 2001     

新型个体化三维矫形胸腰骶气囊支具的有限元研究

目的 运用计算机技术,建立青少年特发性脊柱侧凸（adolescent idiopathic scoliosis,AIS）三维有限元模型,探讨新型个体化气囊支具的矫形效果.方法 建立AIS三维有限元模型,验证模型的有效性.构建支具有限元模型,分别记录在在冠状面、矢状面和两者组合施力情况下的参数,比较矫形效果.结果 顺利完成了AIS和个性化支具的有限元模型,验证模型有效.在冠状面、矢状面、两者结合分别施力,获取最佳胸弯矫正率分别为66%、37%、52%,腰凸矫正率分别为65%、34%、53%;后2种施力方式可以获得较高顶锥旋转度矫正率和更好的矢状面平衡.结论新型支具可以获得良好的冠状面矫正率以及旋转矫正率、并且有助于改善脊柱矢状面曲度,对脊柱侧凸的治疗具有重要意义.     

Association between bone mineral densities and serum lipid profiles of pre- and post-menopausal rural women in South Korea

The objectives of this population-based study were to investigate the potential association between bone mineral density (BMD) and serum lipid profiles and to compare the effects of serum lipids on BMD at various skeletal sites in pre- and post-menopausal women. In July and August of 2004, BMD was measured at a variety of skeletal sites [lumbar spine (L_1–4), femoral neck, trochanter, Wards triangle, shaft and proximal total hip] using the GE/Bravo Lunar DPX dual-energy X-ray absorptiometer in a South Korean population-based sample of 375 pre-menopausal and 355 post-menopausal rural women aged 19–80 years. The levels of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were inversely associated with BMD in both pre- and post-menopausal women. In the pre-menopausal women, correlations were shown only for lumbar 1–4 (TC: r =–0.12, P <0.05; LDL-C: r =–0.12, P <0.05), whereas in the post-menopausal women, no correlation was evident for the lumbar sites. In the post-menopausal subjects, the TC levels showed significant correlations with the BMD values at the trochanter ( r =–0.15, P <0.01), shaft ( r =–0.16, P <0.001) and proximal total hip ( r =–0.15, P <0.01) sites, while the LDL-C levels showed significant correlations with the BMD values at the neck ( r =–0.13, P <0.05), trochanter ( r =–0.21, P <0.001), shaft ( r =–0.20, P <0.001) and proximal total hip ( r =–0.20, P <0.001) sites. The levels of triglyceride (TG) were shown to have a significant positive correlation with BMD values at the trochanter site ( r =0.11, P =0.05) in the post-menopausal women; by contrast, subjects in a higher quartile of TG levels show lower lumbar BMD values in the pre-menopausal women. The levels of high-density lipoprotein cholesterol (HDL-C) were not associated with BMD values at any of the sites in the pre- and post-menopausal subjects. Our data indicate a relationship between BMD values and serum lipid levels and suggest differences between pre- and post-menopausal women in terms of the effects of serum lipids on BMD at various skeletal sites.     

Positive Correlation Between the Femur Neck Shaft and Anteversion Angles: A Retrospective Computed Tomography Analysis in Patients With Developmental Dysplasia of the Hip

BackgroundThis study aimed to explore the anatomical correlation between the femoral neck shaft angle (NSA) and femoral anteversion angle (AA) in patients with developmental dysplasia of the hip based on the Crowe classification and provide a novel method to estimate the femoral AA on anteroposterior pelvic radiographs.MethodsA total of 208 patients with dysplastic hips who underwent total hip arthroplasty at our institution were retrospectively included. Preoperative physiological AA and NSA were determined via 3-dimensional computed tomography. Linear regressions and Pearson’s coefficients were calculated to assess the correlation between the femoral NSA and femoral AA.ResultsA total of 416 hips were divided into 5 subgroups: 99 normal, 143 type I, 71 type II, 63 type III, and 40 type IV hips following the Crowe classification. Dysplastic femurs had significantly higher AAs than normal hips (25.2° vs 31.4° vs 33.3° vs 35.5° vs 41.7°). Significant positive correlations between the AA and NSA were observed in normal (r = 0.635), type I (r = 0.700), type II (r = 0.612), and type III (r = 0.638) hips (P < .001); however, no meaningful correlation was observed in type IV hips (r = 0.218, P = .176).ConclusionThe NSA and AA correlated positively and significantly in the normal and dysplastic Crowe type I-III hips. The relationship between the NSA and AA indicates torsion of the proximal femur and offers an opportunity for straightforward estimation of AA based on NSA.     

Comparison of standard versus reconstruction proximal interlocking screw configurations for antegrade intramedullary nail fixation of femoral shaft fractures

BackgroundThe standard proximal interlocking screw (SS) configuration for antegrade intramedullary nail (IMN) fixation of femoral shaft fractures is lateral to medial or from the greater to less trochanter. Some authors argue for the routine use of the reconstruction screw (RS) configuration (oriented up the femoral neck) instead to prevent femoral neck complications. The purpose of this study was to compare a matched cohort of patients receiving these screw configurations and subsequent complications.MethodsA retrospective review of two urban level-one trauma centers identified adults with isolated femoral shaft fractures undergoing antegrade IMN. Patients with RS and SS configurations were matched 1:1 by age, sex, fracture location, and AO classification in order to compare complications.Results130 patients with femoral shaft fractures were identified. SS and RS configurations were used in 83 (64%) and 47 (36%) patients. 30 patients from each group were able to be matched for analysis. The RS and SS group did not differ in age, fracture location, AO classification, operative time, or number of distal interlocking screws. The RS group had fewer open fractures and were more likely to have two proximal screws. There were 7 complications, including 5 nonunions and 2 delayed unions, with no detectable difference between RS vs. SS groups (10% vs 13%, Proportional difference −3%, 95% confidence interval (CI) −30 to 14%, p = 0.1). There were no femoral neck complications in the entire cohort of 130 patients. On multivariate analysis none of the variables analyzed were independently associated with the development of complications.ConclusionsIn this matched cohort of patients with femoral shaft fractures undergoing antegrade IMN fixation, RS and SS configurations were associated with a similar number of complications and no femoral neck complications. The SS configuration remains the standard for antegrade IMN femoral shaft fixation.Level of evidenceLevel III, Retrospective cohort study.     

Computer-assisted three-dimensional correlation between the femoral neck-shaft angle and the optimal entry point for antegrade nailing

Optimal entry point for antegrade femoral intramedullary nailing (IMN) remains controversial in the current medical literature. The definition of an ideal entry point for femoral IMN would implicate a tenseless introduction of the implant into the canal with anatomical alignment of the bone fragments. This study was undertaken in order to investigate possible existing relationships between the true 3D geometric parameters of the femur and the location of the optimum entry point. A sample population of 22 cadaveric femurs was used (mean age = 51.09 ± 14.82 years). Computed-tomography sections every 0.5 mm for the entire length of femurs were produced. These sections were subsequently reconstructed to generate solid computer models of the external anatomy and medullary canal of each femur. Solid models of all femurs were subjected to a series of geometrical manipulations and computations using standard computer-aided-design tools. In the sagittal plane, the optimum entry point always lied a few millimeters behind the femoral neck axis (mean = 3.5 ± 1.5 mm). In the coronal plane the optimum entry point lied at a location dependent on the femoral neck-shaft angle. Linear regression on the data showed that the optimal entry point is clearly correlated to the true 3D femoral neck-shaft angle (R² = 0.7310) and the projected femoral neck-shaft angle (R² = 0.6289). Anatomical parameters of the proximal femur, such as the varus-valgus angulation, are key factors in the determination of optimal entry point for nailing. The clinical relevance of the results is that in varus hips (neck-shaft angle ≤120°) the correct entry point should be positioned over the trochanter tip and the use stiff nails is advised. In cases of hips with neck-shaft angle between 120° and 130°, the optimal entry point lies just medially to the trochanter tip (at the piriformis fossa) and the use of stiff implants is safe. In hips with neck-shaft angle over 130° the anatomical axis of the canal is medially to the base of the neck, in a “restricted area”. In these cases the entry point should be located at the insertion of the piriformis muscle and the application of more malleable implants that could easily follow the medullary canal should be considered.     

Is retrograde nailing superior to lateral locked plating for complete articular distal femur fractures?

IntroductionNonunion rates for distal femur fractures treated with lateral locked plating (LLP) remains as high as 18–22% despite significant advances with implant design and construct modulation. However, whether treatment of distal femur fractures with rIMN has improved outcomes compared to LLP has not been well characterized. The purpose of this study was to compare outcomes of complete articular distal femur fractures (AO/OTA 33-C) treated with either LLP or rIMN.Methods106 distal femur fractures in 106 patients between January 2014 and January 2018 were identified. Medical records were reviewed to collect patient age, gender, body mass index, sagittal and coronal plane alignment on immediate postoperative radiographs, time to union, incidence of nonunion, and incidence of secondary operative procedures for repair of a nonunion.ResultsOf 106 patients, 50 underwent rIMN and 56 underwent LLP. The mean age at the time of injury was 51 years (21 to 86 years) and there were 55 males. Average coronal alignment of 83.7° of anatomic lateral distal femoral angle (aLDFA) and sagittal alignment of <1° of apex anterior angulation in the rIMN group. In the LLP group there was an average of 87.9° of aLDFA and 1.9° of apex anterior angulation (p = .005 and p = .36). Average time to union in the rIMN group was 6 months and 6.6 months in the LLP group (p = .52). Incidence of nonunion in the rIMN group was 11.8% and 27.5% in the LLP group (p = .008). There were 8 secondary procedures for nonunion in the rIMN group and 18 in the LLP group (p = .43).ConclusionsOur results demonstrated a higher nonunion rate and coronal plane malalignment with LLP compared to rIMN. While prospective data is required, rIMN does appear to be an appropriate treatment for complete articular distal femur fractures with a potentially decreased rate of nonunion .     

Evaluating Alternate Registration Planes for Imageless,Computer-Assisted Navigation During Total Hip Arthroplasty

BackgroundImageless computer navigation improves component placement accuracy in total hip arthroplasty (THA), but variations in the registration process are known to impact final accuracy measurements. We sought to evaluate the registration accuracy of an imageless navigation device during THA performed in the lateral decubitus position.MethodsA prospective, observational study of 94 patients undergoing a primary THA with imageless navigation assistance was conducted. Patient position was registered using 4 planes of reference: the patient’s coronal plane (standard method), the long axis of the surgical table (longitudinal plane), the lumbosacral spine (lumbosacral plane), and the plane intersecting the greater trochanter and glenoid fossa (hip-shoulder plane). Navigation measurements of cup position for each plane were compared to measurements from postoperative radiographs.ResultsMean inclination from radiographs (41.5° ± 5.6°) did not differ significantly from inclination using the coronal plane (40.9° ± 3.9°, P = .39), the hip-shoulder plane (42.4° ± 4.7°, P = .26), or the longitudinal plane (41.2° ± 4.3°, P = .66). Inclination measured using the lumbosacral plane (45.8° ± 4.3°) differed significantly from radiographic measurements (P < .0001). Anteversion measured from radiographs (mean: 26.1° ± 5.4°) did not differ significantly from the hip-shoulder plane (26.6° ± 5.2°, P = .50). All other planes differed significantly from radiographs: coronal (22.6° ± 6.8°, P = .001), lumbosacral (32.5° ± 6.4°, P < .0001), and longitudinal (23.7° ± 5.2°, P < .0001).ConclusionPatient registration using any plane approximating the long axis of the body provided a frame of reference that accurately measured intraoperative cup position. Registration using a plane approximating the hip-shoulder axis, however, provided the most accurate and consistent measurement of acetabular component position.