Necessity of routinely performing foraminoplasty during percutaneous endoscopic transforaminal discectomy in treating lumbar disc herniation / 中华骨科杂志

ABSTRACT

Objective@#To analyze the necessity of routinely performing foraminoplasty during percutaneous transforaminal endoscopic discectomy (PETD).@*Methods@#A total of 412 patients including 231 males and 181 females with an average age of 39.1±13 (20-80) years were enrolled in the present study. All patients were preoperatively diagnosed with single-segment lumbar disc herniation and underwent PETD by the same surgical group. The affected segments were at L3-4 in 32 cases, L4-5 in 289 cases, and L5S1 in 91 cases. Among them, 306 cases had no prolapse, 89 had mild up/down prolapse, and 17 had severe prolapse. MRI sagittal imaging was used to measure the height and width of the intervertebral foramen of L3, 4, L4, 5 and L5S1 segments, the distance between the lower edge of vertebral pedicle and the upper edge of the lower vertebral pedicle and the distance between the point 3 mm to the ventral side of the intervertebral space to the superior articular process. The necessity of performing foraminoplasty was evaluated by measuring the change of intervertebral foramen width using dynamic X-ray and verified during operation.@*Results@#The height of the intervertebral foramen of L3,4, L4,5 and L5S1 segments were 1.99±0.25, 1.89±0.15 and 1.52±0.26 cm, respectively. The width of the intervertebral foramen was 0.78±0.14, 0.75±0.13 and 0.64±0.13 cm, respectively. The distance between the lower edge of vertebral pedicle and the upper edge of the lower vertebral pedicle were 1.14±0.17, 1.05±0.16, and 0.98±0.19 cm, respectively. The distance between the point 3 mm to the ventral side of the intervertebral space to the superior articular process were 1.11±0.31, 1.17±0.20, and 0.95±0.14 cm, respectively. The width of the intervertebral foramen of the L3, 4 and L4,5 segments was significantly greater at the over-flexion position than at the over-extension position (P<0.05). Intraoperative verification showed that 347 cases (group A) did not need foraminoplasty. However, the other 65 patients (group B) needed foraminoplasty, including 31 at L4, 5 segment and 34 at L5S1 segment. One patient in group A and one in group B underwent revision operation due to residual intervertebral disc. At 2 years of follow-up, recurrence occurred in 4 patients in group A and 2 patients in group B. The ODI score and JOA score in group A and B were 18%±9%, 24.2±1.3 and 16%±7%, 23.9±1.3, respectively. There were not significantly different between patients in group A and B (t=1.70, P=0.090; t=1.71, P=0.088). The VAS score of lumbar pain of patients in group A was better than that of patients in group B (P<0.05).@*Conclusion@#Most of PETD of L3-S1 segments can reach the therapeutic target without performing foraminoplasty with half-half technique combined with far lateral access technique. Due to the special anatomical position of L5-S1 segment, the probability of performing foraminoplasty during operation is much higher. Performing foraminoplasty or not depends on the preoperative measurement of foramina and verification during the operation.