The clinical outcome of the treatment of isthmic spondylolysis with Smiley face rod fixation system / 中国脊柱脊髓杂志

ABSTRACT

Objectives:To investigate the clinical outcome of Smiley face rod fixation system for lumbar isthmic spondylolysis.Methods:From January 2016 to June 2017,18 patients with isthmic spondylolysis were treated with smiley face screw-rod fixation system.There were 13 males and 5 females,with an average age of 28.2±3.2(25-32) years old.The average disease duration was 16.3±5.7(7-24) months.L5 isthmic spondylolysis was involved in all cases.All patients had been followed up at 3 months and 1 year after surgery.The preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) were compared.The X-ray and CT scan were evaluated to analyze the change of range of motion in the lumber spine and the bony fusion rate.Results:The mean operation time was 90.0±24.1 minutes.The average blood loss was 140±15ml.The average follow-up was 18.5±5.0 (12-24) months.The VAS at 3 months after operation was 3.0±1.2,and the ODI was (17.2±4.5)％ respectively,which showed significant differences compared with the preoperative ones[7.3±2.5 and (67.0±15.1)％](P＜0.05).The VAS and ODI at 1 year after operation were 1.0± 0.6 and (9.1±5.3)％,which showed significant differences compared with 3 months postoperation(P＜0.05).The range of motion between L5 and S1 was 13.1°±2.1° and the incidence of lumbar instability was 83.3％(15/18) preoperatively;it was 9.3°±1.6° and 11.1％(2/18) postoperatively,and there was statistic difference(P＜0.05).All patients achieved bone fusion in the isthmic defect 1 year after operation.Conclusions:The Smiley face rod fixation is a reliable treatment for lumbar spondylolysis with the advantage of minimal invasive,less nerve interference,and to restore normal anatomical structure,maintain the lumbar spine stability.