Schanz钉结合顶棒技术在外展嵌插型股骨颈骨折中的应用

Reduction of valgus-impacted femoral neck fractures by Schanz screw combined with rod stick technique

目的探讨Schanz钉结合顶棒技术复位后股骨颈动力交叉钉系统(femoral neck system,FNS)固定治疗外展嵌插型股骨颈骨折的临床疗效。方法回顾性分析2019年12月至2021年11月采用股骨颈动力交叉钉系统治疗的外展嵌插型股骨颈骨折患者66例。辅助组(采用Schanz钉结合顶棒技术复位)32例,男9例、女23例,年龄(52.7±12.0)岁(范围28~77岁),左侧14例、右侧18例,体质指数(23.1±2.6)kg/m2;手法组(采用传统Flynn闭合复位)34例,男18例、女16例,年龄(52.1±12.7)岁(范围26~75岁),左侧18例、右侧16例,体质指数(23.4±2.3)kg/m2。记录并比较两组患者手术时间、术中出血量及并发症、末次随访时Harris髋关节评分,分别在髋关节正侧位X线片测量手术前后外展角、后倾角以及末次随访时股骨颈短缩程度。采用Pearson相关性分析对手术前后的外展角、后倾角及末次随访股骨颈短缩程度与Harris髋关节评分的相关性进行分析。结果辅助组与手法组性别、年龄、损伤侧别、身高、体重、体质指数等基线资料及手术时间、术中出血量的差异均无统计学意义(P>0.05)。66例随访时间平均20.4个月(范围12~29个月),辅助组骨折愈合时间(5.0±0.9)周,手法组(4.9±0.8)周,差异无统计学意义(t=-0.41,P>0.05)。61例(92%)合并股骨头后倾,其中30例(46%)后倾角>10°;辅助组术前外展角、后倾角与手法组的差异均无统计学意义(P>0.05);辅助组术后外展角、后倾角(1.8°±3.1°、1.2°±3.0°)均低于手法复位组(13.7°±6.5°、6.8°±4.1°),差异有统计学意义(t=-9.55,P<0.001;t=-7.42,P<0.001)。辅助组末次随访短缩程度(1.4±2.1)mm及术后股骨颈中度、重度短缩发生率(0、3.1%)均低于手法组[(8.1±4.8)mm、38.2%、32.4%],差异有统计学意义(P<0.05)。辅助组末次随访Harris评分(91.1±4.5)分高于手法组(85.5±5.4)分,差异有统计学意义(t=4.54,P<0.001)。术后外展角、股骨颈短缩程度与Harris评分均具有负相关(r=-0.55,P<0.001;r=-0.74,P<0.001)。辅助组1例术中临时固定克氏针断裂,2例Schanz钉复位过程中松动、退钉。术后3例(辅助组1例、手法组2例)分别为术后18、18、24个月发生股骨头坏死,均行人工全髋关节置换。结论采用Schanz钉结合顶棒技术复位股骨颈动力交叉钉系统固定治疗外展嵌插型股骨颈骨折可有效矫正术前外展角、后倾角,降低术后股骨颈短缩程度等特点,早中期疗效满意。

Objective To investigate the clinical efficacy of the femoral neck system(FNS)after the reduction of the Schanz screw combined with the rod stick technique in the treatment of valgus-impacted femoral neck fracture.MethodsA retrospective analysis of clinical data from 66 patients with valgus-impacted femoral neck fractures from December 2019 to November 2021 has been performed.All patients were treated with the Femoral Neck System.Auxiliary reduction group(using the Schanz screw and rod stick technique),including 32 cases,9 males and 23 females with an average age of 52.7±12.0 years(range,28-77 years);14 patients on the left side and 18 patients on the right side;body mass index 23.1±2.6 kg/m2.Manual reduction group(using the traditional Flynn closed reduction technique),including 34 cases,18 males and 16 females with an average age of 52.1±12.7 years(range,26-75 years);18 patients on the left side and 16 patients on the right side;body mass index 23.4±2.3 kg/m2.The surgery time,intraoperative blood loss,complications,and Harris hip score at the last follow-up were collected and compared between the two groups.Preoperative and postoperative abduction angle and posterior tilt angle were measured in the anterior-posterior and lateral positions of the hip,as well as the length of the femoral neck shortening at the last follow-up.Pearson analysis was used to evaluate the correlation between preoperative and postoperative abduction angle and posterior tilt angle,the length of femoral neck shortening,and Harris hip score.ResultsThere were no significant differences in baseline data such as gender,age,side of injury,height,weight,and body mass index,and the surgery time and intraoperative blood loss between auxiliary reduction group and manual reduction group(P>0.05).All 66 cases with a mean follow-up of 20.4 months(ranges 12-29 mouths).The fracture healing time was 5.0±0.9 weeks in the auxiliary reduction group and 4.9±0.8 weeks in the manual reduction group(t=-0.41,P>0.05).There were no significant statistical difference in the preoperative abduction angle and preoperative posterior tilt angle between the auxiliary reduction group and the manual reduction group(P>0.05).The postoperative abduction angle and posterior tilt angle of the auxiliary reduction group(1.8°±3.1°,1.2°±3.0°)were significantly lower than those of the manual reduction group(13.7°±6.5°,6.8°±4.1°,t=-9.55,P<0.001;t=-7.42,P<0.001).Preoperatively,61 cases(92%)were associated with a posterior tilt of the femoral head,and 30(46%)of them had a posterior tilt angle of more than 10°.The length of femoral neck shortening at the last follow-up and the moderate and severe femoral neck shortening rate postoperatively in the auxiliary reduction group(1.4±2.1 mm,0,and 3%)were significantly lower than those in the manual reduction group(8.1±4.8 mm,38%,and 32%,P<0.05).Harris hip score at the last follow-up in the auxiliary reduction group 91.1±4.5 was significantly higher than those in the manual reduction group 85.5±5.4(t=4.54,P<0.001).The postoperative abduction angle and length of femoral neck shortening showed correlations with the Harris hip score respectively(r=-0.551,-0.743;P<0.001).In the auxiliary reduction group,1 case of broken temporary fixed Kirschner wire was removed by nucleus pulposus forceps,and the fracture site healed after surgery.In 2 cases,the Schanz screw loosened and pulled out during the reduction process,and the successful reduction was achieved after increasing the depth of the Schanz screw insertion,and no peri-Schanz screw fracture occurred.After surgery,3 cases(1 case in the auxiliary reduction group and 2 cases in the manual reduction group)developed avascular necrosis of the femoral head(18 months,18 months,and 2 years after surgery,respectively),femoral head collapse and severe shortening of the femoral neck,all of which underwent total hip arthroplasty.ConclusionFNS after the reduction of the Schanz screw combined with the rod stick technique in the treatment of valgus-impacted femoral neck fracture has the advantages of effectively correcting preoperative abduction angle and posterior tilt angle and reducing the length of femoral neck shortening,and it can obtain satisfactory short and medium-term clinical efficacy.