Effect Of Iliac Crest Height On Percutaneous Endoscopic Transforaminal Discectomy For The Treatment Of L5/S1 Disc Herniation

Objective: To investigate the effect of iliac crest height on the treatment of L5 / S1 disc herniation by percutaneous endoscopic transforaminal discectomy.Methods: Clinical data about 172 L5 / S1 disc herniation patients who underwent PETD in our hospital from October 2014 to October 2015 were retrospectively analyzed.According to the positional relationship between the highest point of the iliac crest and the L4 and L5 pedicle of the lumbar lateral radiograph, the study was divided into 3 groups: Group I is that the highest point of the iliac crest is below the upper margin of the L5 pedicle. Group II is the point between the lower margin of the L4 pedicle and the upper margin of the L5 pedicle. Group III is the point above the lower margin of the L4 pedicle.Operation time, fluoroscopy time, and complication between the three groups were compared. Clinical outcomes were assessed by the Visual Analogue Scale(VAS), the Oswestry Disability Index (ODI), and the modified MacNab criteria.Resules: The operations were completed in all the patients.The operation time was prolonged in group ?-? with (50.6 ± 7.0) min, (61.9 ± 9.6) min and (73.1 ± 8.0)min,resprctively,showing significant difference(P <0.05) ; The fluoroscopy time was prolonged in group ?-? with (4.7 ± 2.2) s, (7.4 ± 3.1) s,(10.3 ± 2.5)s,resprctively,showing significant difference(P <0.05) ;The VAS and ODI scores of each group were statistically different from those before operation (P <0.05). There was no significant difference in VAS score and ODI score between groups at the same time point (P> 0.05). According to the improved MacNab scoring system, the excellent and good rate of three months after operation were 89.7%, 89.6% and 87.5% respectively.Conclusion: In the treatment of L5/S1 disc herniation with PETD, when the iliac crest is below the upper margin of the L5 pedicle, the operation is generally complete; when the iliac crest is between the lower margin of the L4 pedicle and the upper margin of the L5 pedicle, the experienced surgeon can complete; when the iliac crest is above the lower margin of the L4 pedicle, it is recommended to use other surgical approach.