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L5 spinal nerve function after L5-S1 high-grade spondylolisthesis reduction: Two case reports
Journal of the Neurological Sciences 375 (2017) 321–323
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Letter to the Editor L5 spinal nerve function after L5-S1 high-grade spondylolisthesis reduction: Two case reports☆,☆☆ Keywords: High-grade spondylolisthesis L5 nerve palsy Radiculopathy Sagittal balance
High-grade spondylolisthesis at the lumbosacral junction (L5-S1) presents unique treatment challenges [1]. The traditional surgical treatment predicates in-situ fusion, either postero-lateral [2] (between the transverse process of L5 and the sacral ala) or transsacral transdiscal [3]. Recently, awareness of spinopelvic sagittal alignment importance [4,5] has prompted the need for spondylolisthesis reduction before the fusion [6–8]. However, the major perceived risk with surgical reduction is the L5 spinal nerve palsy, due to stretching of this nerve over the L5 vertebral body [9,10]. We report two cases of high-grade spondylolisthesis who underwent complete reduction and L5-S1 instrumented fusion and experienced no neurological deficit at 3 months.
Case reports The first patient is a 42-year-old female with many years history of low back pain radiating into both lower extremities down to the feet. The neurological examination was normal. The imaging showed a Meyerding grade 3 spondylolisthesis at L5-S1 (60%). The pelvic tilt (PT) was 19°, the pelvic incidence (PI) was 79°, and the lumbar lordosis (LL) was 71°, for a PI-LL = 8. After informed consent was obtained, the patient underwent a bilateral L5 laminectomy and facetectomy, followed by decompression of the L5 spinal nerves and dorsal root ganglia, instrumented reduction and fixation, and interbody cage and graft insertion. The L5 pedicle screws had bicortical purchase, in order to maximize pullout strength. The reduction was performed by locking the rods on the S1 pedicle screws, and then slowly bringing the L5 pedicle screw heads to the rods, using the reduction towers, thus realigning the L5 and S1 vertebral bodies. The patient tolerated the procedure well and there were no postoperative deficits. The radicular pain resolved immediately after surgery and the axial back pain resolved by the 3-month postoperative follow-up visit. A lumbar CT showed good placement of
☆ The article has not been previously published or submitted for publication. ☆☆ The authors have no conflicts of interest.
http://dx.doi.org/10.1016/j.jns.2017.02.035 0022-510X/© 2017 Elsevier B.V. All rights reserved.
the instrumentation and complete reduction of the spondylolisthesis (grade 0, 0%) (Fig. 1). The second patient is a 22-year-old female with a 2-year history of low back pain radiating in the left lower extremity in L5 distribution. The neurological examination revealed mild (Asia grade 4+/5) extensor hallucis longus and foot dorsiflexion weakness. The imaging showed a Meyerding grade 4 spondylolisthesis at L5-S1 (82%). The PT was 36°, the PI was 82°, and the LL was 47°, for a PI-LL = 35. After informed consent was obtained, the patient underwent an initial instrumented reduction and fixation (as described in the previous case), followed by unilateral left-sided laminectomy, facetectomy, discectomy, and interbody cage and graft insertion. The motor deficit persisted in the immediate postoperative period, but resolved by the 3-month follow-up visit. The pain also completely subsided at the 3-month visit. A postoperative lumbar CT showed the complete spondylolisthesis reduction (grade 0, 0%) (Fig. 2).
Discussion The L5 palsy is the most feared complication following reduction of high-grade L5-S1 spondylolisthesis [9,10]. However, the reduction allows for restoration of spinopelvic sagittal alignment [4,5] and provides a large interbody fusion surface, two advantages that increase longterm success [6–8]. To prevent nerve damage during the reduction, some authors advocated keeping the patients in a hip- and knee-flexed position postoperatively, and then gradually straighten the legs over several days [9]. In our two cases, we had the patients prone in neutral position, since we did not want to fuse the L5-S1 segment in kyphosis. However, we did perform the instrumented reduction very slowly, with 3-minute breaks after each 2 mm reduced. Another common perception is that the L5 spinal nerves need to be decompressed prior to spondylolisthesis reduction. However, the posterior decompression has no significance, since the nerves are stretched over the anterior vertebral body. The only potential benefit of exposing the L5 spinal nerves is the release of any adhesions between the nerve and the vertebral body, thus allowing the nerve to “glide” over the vertebral body during the reduction. However, we have not observed such adhesions in any of the high-grade spondylolisthesis cases performed. Therefore, we did not expose the nerves in the second case presented, and yet no deficit occurred, which suggests that exposure and decompression may not be needed in every case. Finally, most authors recommend multilevel fixation in order to achieve adequate reduction [5–7,9]. Our cases demonstrate that a simple L5-S1 construct is sufficient to completely reduce high-grade spondylolistheses, albeit the L5 screws should be bicortical, in order to maximize pullout strength. In conclusion, our case reports show that patients with high-grade L5-S1 spondylolisthesis can be treated by a single-level instrumented reduction and fusion, without incurring an L5 radicular deficit.
322
Letter to the Editor
Fig. 1. Patient 1. Upper left, Preoperative lateral X-ray showing the grade 3 spondylolisthesis. Upper middle and right, Intraoperative lateral fluoroscopic images showing the L5-S1 segment before and after instrumented reduction. Lower left and middle, Intraoperative lateral and AP fluoroscopic images showing the final construct, after bilateral cage insertion. Lower right, Postoperative computed-tomography sagittal reconstruction showing the L5-S1 realignment.
Fig. 2. Patient 2. Upper left, Preoperative sagittal T2 magnetic resonance imaging showing the grade 4 spondylolisthesis. Upper middle and right, Intraoperative lateral fluoroscopic images showing the L5-S1 segment before and after instrumented reduction, before cage insertion. Lower left and middle, Postoperative computed-tomography sagittal reconstruction showing the L5-S1 realignment. Lower right, Postoperative AP X-ray showing the final construct.
Letter to the Editor
References [1] P.G. Passias, C.E. Poorman, S. Yang, et al., Surgical treatment strategies for high-grade spondylolisthesis: a systematic review, Int. J. Spine Surg. 9 (2015) 50. [2] P.D. Pizzutillo, W. Mirenda, G.D. MacEwen, Posterolateral fusion for spondylolisthesis in adolescence, J. Pediatr. Orthop. 6 (1986) 311–316. [3] M.D. Smith, H.H. Bohlman, Spondylolisthesis treated by a single-stage operation combining decompression with in situ posterolateral and anterior fusion. An analysis of eleven patients who had long-term follow-up, J. Bone Joint Surg. Am. 72 (1990) 415–421. [4] H. Labelle, J.M. Mac-Thiong, P. Roussouly, Spino-pelvic sagittal balance of spondylolisthesis: a review and classification, Eur. Spine J. 20 (Suppl. 5) (2011) 641–646. [5] A. Harroud, H. Labelle, J. Joncas, J.M. Mac-Thiong, Global sagittal alignment and health-related quality of life in lumbosacral spondylolisthesis, Eur. Spine J. 22 (2013) 849–856. [6] H.L. Shufflebarger, M.J. Geck, High-grade isthmic dysplastic spondylolisthesis: monosegmental surgical treatment, Spine 30 (2005) S42–S48. [7] F. Omidi-Kashani, A. Hootkani, L. Jarahi, M. Rezvan, A. Moayedpour, Radiologic and clinical outcomes of surgery in high grade spondylolisthesis treated with temporary distraction rod, Clin. Orthop. Surg. 7 (2015) 85–90. [8] W. Tian, X.G. Han, B. Liu, et al., Posterior reduction and monosegmental fusion with intraoperative three-dimensional navigation system in the treatment of high-grade developmental spondylolisthesis, Chin. Med. J. 128 (2015) 865–870. [9] C. Karampalis, M. Grevitt, M. Shafafy, J. Webb, High-grade spondylolisthesis: gradual reduction using Magerl's external fixator followed by circumferential fusion technique and long-term results, Eur. Spine J. 21 (Suppl. 2) (2012) S200–S206.
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[10] M.K. Kasliwal, J.S. Smith, C.I. Shaffrey, et al., Short-term complications associated with surgery for high-grade spondylolisthesis in adults and pediatric patients: a report from the scoliosis research society morbidity and mortality database, Neurosurgery 71 (2012) 109–116.
Gabriel Tender Department of Neurosurgery, Louisiana State University, 2020 Gravier Street, Suite 744, New Orleans, LA, USA Corresponding author. E-mail address: [email protected]. Daniel Serban Niki Calina Mihaela Florea “Bagdasar-Arseni” Hospital, 10-12 Berceni, Bucharest, Romania E-mail addresses: [email protected] (D. Serban), [email protected] (N. Calina), fl[email protected] (M. Florea). 12 November 2016
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Letter to the Editor L5 spinal nerve function after L5-S1 high-grade spondylolisthesis reduction: Two case reports☆,☆☆ Keywords: High-grade spondylolisthesis L5 nerve palsy Radiculopathy Sagittal balance
High-grade spondylolisthesis at the lumbosacral junction (L5-S1) presents unique treatment challenges [1]. The traditional surgical treatment predicates in-situ fusion, either postero-lateral [2] (between the transverse process of L5 and the sacral ala) or transsacral transdiscal [3]. Recently, awareness of spinopelvic sagittal alignment importance [4,5] has prompted the need for spondylolisthesis reduction before the fusion [6–8]. However, the major perceived risk with surgical reduction is the L5 spinal nerve palsy, due to stretching of this nerve over the L5 vertebral body [9,10]. We report two cases of high-grade spondylolisthesis who underwent complete reduction and L5-S1 instrumented fusion and experienced no neurological deficit at 3 months.
Case reports The first patient is a 42-year-old female with many years history of low back pain radiating into both lower extremities down to the feet. The neurological examination was normal. The imaging showed a Meyerding grade 3 spondylolisthesis at L5-S1 (60%). The pelvic tilt (PT) was 19°, the pelvic incidence (PI) was 79°, and the lumbar lordosis (LL) was 71°, for a PI-LL = 8. After informed consent was obtained, the patient underwent a bilateral L5 laminectomy and facetectomy, followed by decompression of the L5 spinal nerves and dorsal root ganglia, instrumented reduction and fixation, and interbody cage and graft insertion. The L5 pedicle screws had bicortical purchase, in order to maximize pullout strength. The reduction was performed by locking the rods on the S1 pedicle screws, and then slowly bringing the L5 pedicle screw heads to the rods, using the reduction towers, thus realigning the L5 and S1 vertebral bodies. The patient tolerated the procedure well and there were no postoperative deficits. The radicular pain resolved immediately after surgery and the axial back pain resolved by the 3-month postoperative follow-up visit. A lumbar CT showed good placement of
☆ The article has not been previously published or submitted for publication. ☆☆ The authors have no conflicts of interest.
http://dx.doi.org/10.1016/j.jns.2017.02.035 0022-510X/© 2017 Elsevier B.V. All rights reserved.
the instrumentation and complete reduction of the spondylolisthesis (grade 0, 0%) (Fig. 1). The second patient is a 22-year-old female with a 2-year history of low back pain radiating in the left lower extremity in L5 distribution. The neurological examination revealed mild (Asia grade 4+/5) extensor hallucis longus and foot dorsiflexion weakness. The imaging showed a Meyerding grade 4 spondylolisthesis at L5-S1 (82%). The PT was 36°, the PI was 82°, and the LL was 47°, for a PI-LL = 35. After informed consent was obtained, the patient underwent an initial instrumented reduction and fixation (as described in the previous case), followed by unilateral left-sided laminectomy, facetectomy, discectomy, and interbody cage and graft insertion. The motor deficit persisted in the immediate postoperative period, but resolved by the 3-month follow-up visit. The pain also completely subsided at the 3-month visit. A postoperative lumbar CT showed the complete spondylolisthesis reduction (grade 0, 0%) (Fig. 2).
Discussion The L5 palsy is the most feared complication following reduction of high-grade L5-S1 spondylolisthesis [9,10]. However, the reduction allows for restoration of spinopelvic sagittal alignment [4,5] and provides a large interbody fusion surface, two advantages that increase longterm success [6–8]. To prevent nerve damage during the reduction, some authors advocated keeping the patients in a hip- and knee-flexed position postoperatively, and then gradually straighten the legs over several days [9]. In our two cases, we had the patients prone in neutral position, since we did not want to fuse the L5-S1 segment in kyphosis. However, we did perform the instrumented reduction very slowly, with 3-minute breaks after each 2 mm reduced. Another common perception is that the L5 spinal nerves need to be decompressed prior to spondylolisthesis reduction. However, the posterior decompression has no significance, since the nerves are stretched over the anterior vertebral body. The only potential benefit of exposing the L5 spinal nerves is the release of any adhesions between the nerve and the vertebral body, thus allowing the nerve to “glide” over the vertebral body during the reduction. However, we have not observed such adhesions in any of the high-grade spondylolisthesis cases performed. Therefore, we did not expose the nerves in the second case presented, and yet no deficit occurred, which suggests that exposure and decompression may not be needed in every case. Finally, most authors recommend multilevel fixation in order to achieve adequate reduction [5–7,9]. Our cases demonstrate that a simple L5-S1 construct is sufficient to completely reduce high-grade spondylolistheses, albeit the L5 screws should be bicortical, in order to maximize pullout strength. In conclusion, our case reports show that patients with high-grade L5-S1 spondylolisthesis can be treated by a single-level instrumented reduction and fusion, without incurring an L5 radicular deficit.
322
Letter to the Editor
Fig. 1. Patient 1. Upper left, Preoperative lateral X-ray showing the grade 3 spondylolisthesis. Upper middle and right, Intraoperative lateral fluoroscopic images showing the L5-S1 segment before and after instrumented reduction. Lower left and middle, Intraoperative lateral and AP fluoroscopic images showing the final construct, after bilateral cage insertion. Lower right, Postoperative computed-tomography sagittal reconstruction showing the L5-S1 realignment.
Fig. 2. Patient 2. Upper left, Preoperative sagittal T2 magnetic resonance imaging showing the grade 4 spondylolisthesis. Upper middle and right, Intraoperative lateral fluoroscopic images showing the L5-S1 segment before and after instrumented reduction, before cage insertion. Lower left and middle, Postoperative computed-tomography sagittal reconstruction showing the L5-S1 realignment. Lower right, Postoperative AP X-ray showing the final construct.
Letter to the Editor
References [1] P.G. Passias, C.E. Poorman, S. Yang, et al., Surgical treatment strategies for high-grade spondylolisthesis: a systematic review, Int. J. Spine Surg. 9 (2015) 50. [2] P.D. Pizzutillo, W. Mirenda, G.D. MacEwen, Posterolateral fusion for spondylolisthesis in adolescence, J. Pediatr. Orthop. 6 (1986) 311–316. [3] M.D. Smith, H.H. Bohlman, Spondylolisthesis treated by a single-stage operation combining decompression with in situ posterolateral and anterior fusion. An analysis of eleven patients who had long-term follow-up, J. Bone Joint Surg. Am. 72 (1990) 415–421. [4] H. Labelle, J.M. Mac-Thiong, P. Roussouly, Spino-pelvic sagittal balance of spondylolisthesis: a review and classification, Eur. Spine J. 20 (Suppl. 5) (2011) 641–646. [5] A. Harroud, H. Labelle, J. Joncas, J.M. Mac-Thiong, Global sagittal alignment and health-related quality of life in lumbosacral spondylolisthesis, Eur. Spine J. 22 (2013) 849–856. [6] H.L. Shufflebarger, M.J. Geck, High-grade isthmic dysplastic spondylolisthesis: monosegmental surgical treatment, Spine 30 (2005) S42–S48. [7] F. Omidi-Kashani, A. Hootkani, L. Jarahi, M. Rezvan, A. Moayedpour, Radiologic and clinical outcomes of surgery in high grade spondylolisthesis treated with temporary distraction rod, Clin. Orthop. Surg. 7 (2015) 85–90. [8] W. Tian, X.G. Han, B. Liu, et al., Posterior reduction and monosegmental fusion with intraoperative three-dimensional navigation system in the treatment of high-grade developmental spondylolisthesis, Chin. Med. J. 128 (2015) 865–870. [9] C. Karampalis, M. Grevitt, M. Shafafy, J. Webb, High-grade spondylolisthesis: gradual reduction using Magerl's external fixator followed by circumferential fusion technique and long-term results, Eur. Spine J. 21 (Suppl. 2) (2012) S200–S206.
323
[10] M.K. Kasliwal, J.S. Smith, C.I. Shaffrey, et al., Short-term complications associated with surgery for high-grade spondylolisthesis in adults and pediatric patients: a report from the scoliosis research society morbidity and mortality database, Neurosurgery 71 (2012) 109–116.
Gabriel Tender Department of Neurosurgery, Louisiana State University, 2020 Gravier Street, Suite 744, New Orleans, LA, USA Corresponding author. E-mail address: [email protected]. Daniel Serban Niki Calina Mihaela Florea “Bagdasar-Arseni” Hospital, 10-12 Berceni, Bucharest, Romania E-mail addresses: [email protected] (D. Serban), [email protected] (N. Calina), fl[email protected] (M. Florea). 12 November 2016