Objective: To investigate the clinical efficacy of oblique lumbar interbody fusion(OLIF) combined with posterior percutaneous internal fixation in patients with lumbar spinal stenosis with or without redundant nerve roots(RNRs).
Methods: A retrospective analysis of 92 patients with lumbar spinal stenosis treated by oblique lateral lumbar interbody fusion combined with posterior percutaneous internal fixation from June 2019 to June 2022 was performed. There were 32 males and 60 females, aged from 44 to 82 years old with an average of (63.67±9.93) years old. All patients were divided into RNRs positive group and RNRs negative group according to redundancy or not before operation. There were 38 patients in RNRs positive group, including 15 males and 23 females. The age ranged from 45 to 82 years old with an average of (65.45±10.37) years old. The disease duration was 24.00(12.00, 72.00) months. There were 54 patients in RNRs negative group, including 17 males and 37 females. The age ranged from 44 to 77 years old with an average of (62.42±9.51) years old. The disease duration was 13.50(9.00, 36.00) months. The general data of patients were recorded, including operation time, intraoperative blood loss and complications. The imaging parameters before and after operation were observed, including the number of stenosis segments, intervertebral space height, lumbar lordosis angle and dural sac area. The visual analogue scale (VAS) was used to evaluate the back and lower extremity pain, and the Oswestry disability index (ODI) was used to evaluate the activities of daily living.
Results: All patients were followed up for 8 to 18 months with an average of (11.04±3.61) months, and no complications were found during the follow-up period.The number of stenosis segments in RNRs positive group (1.71±0.46) was more than that in RNRs negative group(1.17±0.38). In RNRs positive group, intervertebral space height, dural sac area, low back pain VAS, lower extremity pain VAS, ODI score were (1.11±0.19) cm, (0.46±0.17) cm2, (5.39±1.00) scores, (5.05±1.01) points, (55.74±4.05) points, respectively. RNRs negative groups respectively (0.97±0.23) cm, (0.69±0.26) cm2, (4.50±0.77) scores, (4.00±0.58) scores, (47.33±3.43) %. In RNRs positive group, intervertebral space height, dural sac area, low back pain VAS, leg pain VAS, ODI score were (1.60±0.19) cm, (0.74±0.36) cm2, (3.39±0.72) scores, (3.05±1.01) scores, (46.74±4.82) scores, respectively. RNRs negative groups respectively (1.48±0.25) cm, (1.12±0.35) cm2, (3.00±0.82) scores, (3.00±0.82) scores, (37.67±3.58) %. The postoperative intervertebral space height, dural sac area, low back pain VAS score, lower extremity pain VAS and ODI score of the patients in the RNRs positive group and the negative group were significantly improved compared with those before operation, and the differences were statistically significant (P<0.05). There were statistically significant differences in the number of stenosed segments, preoperative intervertebral space height, dural sac area, low back pain VAS, lower extremity pain VAS, and ODI between the two groups(P<0.05). There were significant differences in postoperative intervertebral space height and postoperative ODI between the two groups(P<0.05), but there was no significant difference in intervertebral space height before and after operation and ODI score before and after operation(P>0.05). There were significant differences in operation time, intraoperative blood loss, postoperative dural sac area, difference of dural sac area before and after operation, postoperative low back pain VAS, difference of low back pain VAS score before and after operation, difference of lower extremity pain VAS before and after operation between the two groups(P<0.05).
Conclusion: OLIF combined with posterior percutaneous internal fixation has a good effect on patients with or without RNRs. Multi-segmental lumbar spinal stenosis and decreased dural sac area may lead to the occurrence of RNRs, and LSS patients with RNRs have more severe symptoms. LSS patients with RNRs have worse surgical outcomes than those without RNRs.
Keywords: Lumbar spinal stenosis; Oblique lateral lumbar interbody fusion; Posterior percutaneous internal fixation; Redundant nerve roots.