单椎体压缩骨折PKP术后原椎体引起背痛复发因素的探讨

An analysis of recurrent back pain induced by primary single vertebral compression fracture after percutaneous kyphoplasty

目的探讨骨质疏松性单节段椎体骨折经皮椎体后凸成形术（percutoneous kyphoplasty,PKP）后,责任椎体引起背部疼痛复发的原因,为预防和临床治疗提供参考。方法笔者所在单位同一组医生自2006年1月至2009年12月共收治因骨质疏松引起单节段椎体压缩骨折而行PKP的患者共52例,其中28例术后随访〉12个月,其中男11例,女17例;年龄68~86岁,平均（74.13±4.18）岁。随访时间12~34个月,平均（18.50±7.26）个月。按照是否复发背部疼痛分为A、B组：术后未复发背部疼痛为A组（n=20）,术后复发背部疼痛为B组（n=8）。所有患者均记录年龄、性别、症状出现的时间,采用相同手术方法 （PKP）,记录骨水泥注入量（filling PMMP volume,FPV）。手术前、后及复查时均采用视觉模拟评分（visual analogue scale,VAS）评估疼痛程度;通过骨密度（bone mineral density,BMD）比较手术前后及随访时BMD的T评分;通过X线、MRI检查比较手术前后及随访时骨折椎体的压缩率（compression rate,CR）、压缩的恢复率或丢失率,比较手术前后及随访时骨折椎体的后凸角度（kyphotic angle,KA）和后凸角度恢复率或丢失率;比较术后及随访时骨水泥（甲基丙烯酸甲酯）与椎体上下终板间距离（postoperation PMMP to endplate distance,PPED）的改变。对所有数据进行统计学分析。结果背部疼痛复发患者原手术椎体均有不同程度的再骨折或塌陷。A、B组FPV有差异,但无统计学意义。A、B组CR术后均明显增加,两组差异无统计学意义;末次随访时B组CR恢复率为（17.4±9.3）%,A组为（24.1±11.1）%,两组间差异有统计学意义（P〈0.05）;KA呈现同样的改变。A、B两组手术前VAS评分分别为（8.8±0.6）分、（8.6±0.5）分;术后分别为（2.1±0.6）分、（2.2±0.8）分,与术前比较差异有统计学意义（P〈0.05）;B组末次随访时VAS评分为（7.5±1.2）分,与B组术后及A组末次随访（3.1±0.7）分比较,差异有统计学意义（P〈0.05）。A组骨水泥上缘至上终板距离术后与末次随访比较,差异无统计学意义（P〉0.05）;术后A组骨水泥下缘至下终板距离平均为（2.5±0.6）mm,末次随访时为（2.4±0.7）mm,与术后比较差异无统计学意义（P〉0.05）;术后B组骨水泥上缘至上终板距离平均为（3.5±0.4）mm,末次随访时为（2.7±0.9）mm,与术后比较差异有统计学意义（P〈0.05）,术后B组骨水泥下缘至下终板距离平均为（4.5±0.6）mm;末次随访时（3.3±0.4）mm,与术后比较差异有统计学意义（P〈0.05）。结论手术椎体再骨折或塌陷是引起单椎体压缩骨折PKP术后背痛复发的重要原因,适量的FPV可能有利于减少手术椎体再骨折或塌陷。适时监测CR、KA、T评分、PPED的变化可以为预防复发背部疼痛提供参考。

Objective To explore the reasons of recurrent back pain induced by the osteoporosis single vertebral compression fracture after percutaneous kyphoplasty（ PKP） surgery and to provide clinical and preventable guiding. Methods In the authors＇ hospital, 52 patients experienced PKP executed by the same group of doctors from January 2006 to December 2009 due to osteoporosis single vertebral compression fracture. In the 52 patients, 28 patients（ male, 11; female, 12; age 68 to 86 years, averaged 74.13 ± 4.18 years） were followed up for more than 12 months. The duration of the follow-up was from 12 to 34 months（ averaged 18.50 ± 7.26 months）. The patients were divided into 2 groups depending on the recurrent back pain（ Group A： recurrent pain, n = 20; Group B： no pain, n = 8）. Age, gender, and the duration of symptoms were recorded. Patients underwent PKP and the filing PMMP volume（ FPV） was recorded. Preoperatively, postpostoperatively and in the follow-up, visual analogue scale（ VAS） was employed to evaluate the pain. T score was applied to compare the bone mineral density（ BMD）. Compression rate（ CR）, recovery rate of the compression or lost rate of the recovery of the fracture were compared on plain films and MRI images. Kyphosis angle（ KA）, recovery or lost rate of the kyphosis angle were compared on plain films and MRI images. The distance from PMMP to end-plate was compared on plain films. The data were analyzed statistically. Results The primary surgical vertebrae presented refracture or collapse in patients with recurrent back pain. There were differences between Group A and B in FPV but not on statistics. CR increased both in Group A and B without statistical differences postoperatively, but the recovery rate in Group B was（ 17.4 ± 9.3） % compared with that（ 24.1 ± 11.1） % in Group A with statistical differences（ P〈0.05）, and the same trend was seen on KA. The preoperative VAS score were（ 8.8 ± 0.6）,（ 8.6 ± 0.5） in Group A and B respectively comparing those were（ 2.1 ± 0.6）,（ 2.2 ± 0.8） postoperatively with statistical differences（ P〈0.05）. The VAS was（ 7.5 ± 1.2） at the final follow-up in Group B compared with that in Group B postoperatively and that in Group A at the final follow-up（ 3.1 ± 0.7） with statistical significances（ P〈0.05）. In Group A, the distance from the upper end-plate to PMMP were（ 2.2 ± 0.8） mm postoperatively and（ 2.1 ± 0.7） mm at the final follow-up without statistical differences（ P〉0.05）. The distance from the lower end-plate to PMMP were（ 2.5 ± 0.6） mm postoperatively and（ 2.4 ± 0.7） mm at the final follow-up without statistical differences（ P〉0.05）. In Group B, the distance from the upper end-plate to PMMP were（ 3.5 ± 0.4） mm postoperatively and（ 2.7 ± 0.9） mm at the final follow-up with statistical differences（ P〈0.05）. The distance from the lower end-plate to PMMP were（ 4.5 ± 0.6） mm postoperatively and（ 3.3 ± 0.4） mm at the final follow-up with statistical differences（ P〈0.05）. Conclusions The surgical vertebrae refracture or collapse are important reasons for recurrent back pain after PKP for single vertebral compression fracture. Detection of the changes of CR, KA, T-score and PPED can provide guiding for the prevention of recurrent back pain.