经皮短节段内固定治疗Magerl A3伴低骨密度的胸腰椎骨折

Efficacy of percutaneous short segment fixation in the treatment of Magerl A3 thoracolumbar fractures with low bone mineral density:a retrospective study

目的:探讨经皮椎弓根钉短节段内固定加或不加中间螺钉治疗伴有低骨密度的Magerl A3胸腰椎骨折的临床疗效。方法:对2017年1月至2020年7月接受经皮椎弓根钉短节段内固定术的Magerl A3型胸腰椎骨折的患者进行回顾性分析,符合诊断和纳入标准的93例,按排除标准排除9例,余84例获得完整影像学随访资料。男38例,女46例;年龄56~73(64.78±7.12)岁;骨密度0.61~0.89(0.73±0.14)g/cm^(3);随访时间11~25(17.58±6.12)个月。其中加中间螺钉(A组)45例,不加中间螺钉(B组)39例。记录手术时间和术中出血量,采用Oswestry功能障碍指数(Oswestry Disability Index,ODI)和视觉模拟评分法(visual analogue scale,VAS)进行临床评估。根据术后X线片测量Cobb角,椎体楔角(vertebral wedge angle,VWA)和椎体前部高度(anterior vertebral body height,AVBH)进行影像学随访,并计算上述参数的矫正丢失度。结果:84例患者中有5例螺钉松动(A组2例,B组3例,P>0.05);两组在手术时间和术中出血量上差异有统计学意义(P<0.01);两组临床疗效良好,VAS和ODI明显改善,两组在所有随访时间(术后3 d、1个月、末次随访)的VAS和ODI差异均无统计学意义(P>0.05);术后3 d影像学评价(Cobb角、VWA和AVBH)均较术前改善明显(P<0.05),但在术后1个月和末次随访时,两组均可观察到明显的复位丢失(P<0.05)。末次随访时,Cobb角、VWA、AVBH丢失度(差值)A组分别是(5.26±4.18)°,(4.63±3.80)°,(9.54±8.71)%;B组分别是(6.01±4.34)°,(6.55±6.21)°,(11.67±9.95)%;但两组之间的复位丢失比较差异无统计学意义(P>0.05)。结论:增加中间伤椎置钉并不能增加其稳定性,两组经皮短节段内固定均不能抵抗Magerl A3胸腰椎骨折骨折合并低骨密度的复位丢失。由于伤椎螺钉增加了手术时间及术中出血量,因此对低骨密度的老年Magerl A3胸腰椎骨折使用中间螺钉意义不大。

Objective:To explore the clinical efficacy of percutaneous pedicle screw short segment internal fixation with or without the intermediate screw in the treatment of Magerl A3 thoracolumbar fractures with low bone mineral density.Methods:Patients with Magerl A3 thoracolumbar fracture underwent percutaneous pedicle screw short segment internal fixation from January 2017 to July 2020 were retrospectively analyzed,93 cases met the diagnosis and inclusion criteria,9 cases were excluded according to the exclusion criteria,and the remaining 84 cases obtained complete imaging follow-up data.There were 38 males and 46 females,the age ranged from 56 to 73 years old with an average of(64.78±7.12)years old,bone mineral density(BMD)ranged from 0.61 to 0.89 g/cm^(3) with an average of(0.73±0.14)g/cm^(3),the follow-up time was 11 to 25 months with an average of(17.58±6.12)months.There were 45 cases in group A with intermediate screw and 39 cases in group B without intermediate screw.The operation time and intraoperative blood loss were recorded,Oswestry Disability Index(ODI)and visual analogue scale(VAS)were used for clinical evaluation.The Cobb angle,vertebral wedge angle(VWA)and anterior vertebral body height(AVBH)were measured by X-ray after the operation.The corrected loss of the above parameters was calculated.Results:There were 5 cases of screw loosening in 84 patients(2 cases in group A and 3 cases in group B,P>0.05).There were significant differences in operation time and intraoperative blood loss between two groups(P<0.01).Clinical effects of two groups were good,postoperative VAS and ODI after operation obviously improved,there was no significant difference between two groups during all follow-up periods(3 days,1 month after operation and the final follow-up)(P>0.05).Three days after the operation,the image evaluations(Cobb angle,VWA and AVBH)were significantly improved(P<0.05),but significant reduction loss was observed in both groups at 1 month after the operation and at the final follow-up(P<0.05).At the final follow-up,the loss of Cobb angle,VWA and AVBH in group A were(5.26±4.18)°,(4.63±3.80)°and(9.54±8.71)%,respectively;group B was(6.01±4.34)°,(6.55±6.21)°and(11.67±9.95)%,respectively;however,there was no significant difference in reduction loss between the two groups(P>0.05).Conclusion:Although the curative effect of the patients is satisfactory,the stability of the patients can not be improved by increasing the middle injured vertebra screw placement,the two groups of percutaneous short segment internal fixation can not resist the reduction loss of Magerl-A3 thoracolumbar fracture with low bone mineral density.Because the injured vertebra screw increases the operation time and intraoperative blood loss,it is not significant to use the intermediate screw for the elderly Magerl A3 thoracolumbar fractures with low bone mineral density.