Nerve Pinched From Fusion Broken Hardware
Eur Spine J. 2013 May; 22(Suppl iii): 461–465.
L5 spinal nerve injury acquired by misplacement of outwardly-inserted S1 pedicle screws
Masahiro Inoue, Gen Inoue, 
Tomoyuki Ozawa, Masayuki Miyagi, Hiroto Kamoda, Tetsuhiro Ishikawa, Miyako Suzuki, Yoshihiro Sakuma, Yasuhiro Oikawa, Kazuyo Yamauchi, Sumihisa Orita, Masashi Takaso, Tomoaki Toyone, Kazuhisa Takahashi, and Seiji Ohtori
Masahiro Inoue
Department of Orthopaedic Surgery, Graduate Schoolhouse of Medicine, Chiba University, Chiba, Japan
Gen Inoue
Section of Orthopaedic Surgery, Kitasato University, Schoolhouse of Medicine, one-15-1, Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0374 Japan
Tomoyuki Ozawa
Department of Orthopaedic Surgery, Teikyo University Chiba Medical Center, Ichihara, Japan
Masayuki Miyagi
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba Academy, Chiba, Japan
Hiroto Kamoda
Section of Orthopaedic Surgery, Graduate Schoolhouse of Medicine, Chiba University, Chiba, Nippon
Tetsuhiro Ishikawa
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Nippon
Miyako Suzuki
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba Academy, Chiba, Nihon
Yoshihiro Sakuma
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan
Yasuhiro Oikawa
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan
Kazuyo Yamauchi
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba Academy, Chiba, Japan
Sumihisa Orita
Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan
Masashi Takaso
Department of Orthopaedic Surgery, Kitasato Academy, School of Medicine, i-xv-one, Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0374 Nihon
Tomoaki Toyone
Section of Orthopaedic Surgery, Teikyo Academy Chiba Medical Center, Ichihara, Japan
Kazuhisa Takahashi
Section of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Nihon
Seiji Ohtori
Section of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Nihon
Received 2012 Aug 26; Revised 2012 Dec 5; Accepted 2012 Dec 16.
Abstract
Purpose
To evaluate L5 nerve root injuries caused by outwardly misplaced S1 pedicle screws.
Summary of Background Data
Pedicle screws remain the criterion standard for fixation of L5–S1 to correct lumbosacral instability. When inserting S1 pedicle screws, it is possible to injure the L5 nervus root if screws are inserted outwardly and the tip of the screw perforates the inductive cortex of the sacrum. Despite this risk, to our knowledge this type of injury has never been reported equally a case series.
Methods
We experienced 2 cases of L5 nerve root injury caused past outwardly-inserted S1 pedicle screws. In both cases, bilateral S1 pedicle screws were inserted outwardly using a gratuitous-mitt technique, and on one side, screws induced severe pain past impinging on an L5 root. Computed tomography after the selective rootgraphy of the injured nervus showed the nerve compressed laterally by spiral threads in Example 1 and crushed between the spiral threads and the sacral body in Example ii.
Results
In both cases, leg pain disappeared immediately afterwards the infiltration of the nerve with lidocaine, only symptoms recurred within a few days in Case 1 and inside an hr in Example two. Conservative treatment of 3 spinal nervus infiltrations was effective in Example 1, simply reinsertion of the rogue screw was necessary in Case 2.
Conclusions
Surgeons should recognize that lateral inclination of S1 pedicle screws tin cause L5 nerve root injury, which may crave reinsertion of the spiral, especially in cases where insertion is difficult because of overlapping surrounding muscle or bony tissue.
Keywords: Nervus injury, Pedicle screw, Lumbosacral fixation
Introduction
Pedicle screws are widely used in spinal surgery. Numerous articles have reported the effectiveness of pedicle screws [1–six]. Even so, pedicle screws that perforate the pedicle cortex may increase the adventure of neurovascular complications [vii–9]. In a systematic review, the accuracy with which pedicle screws were inserted using a gratuitous-mitt technique was reported every bit from 69 to 100 %, which is lower than the accuracy obtained with fluoroscopic assist or Computed tomography (CT) navigation [10, 11].
Pedicle screws are all the same generally used to fuse L5–S1 in lumbosacral fixation for correction of lumbosacral instability [12–fourteen]. Various methods for the insertion of sacral pedicle screws accept been reported. Bicortical or tricortical methods that penetrate the anterior sacral cortex or cranial S1 endplate are manifestly more than stable than monocortical methods that penetrate the posterior cortex solitary. However, these methods carry a adventure of nerve or vascular injury in forepart of the sacrum when sacral pedicle screws are inserted inwardly [15–24]. Conversely, on the anterolateral side of the S1 sacral bone, L5 nerve roots are arranged from the center cranially to laterally and can be injured if an S1 pedicle spiral is inserted outwardly and perforates the anterior cortex. Despite this take a chance of injury, to our knowledge there has been no previously published report of any L5 nerve root injury acquired by an outwardly-inserted S1 pedicle screw perforating the anterior cortex of sacrum. Ii cases in which the L5 spinal nerve was injured after insertion of S1 pedicle screws are currently reported, for which reinsertion was required in one case only not in the other.
Example 1
A 68-year-old human was diagnosed with spondylolisthesis and referred to our university hospital later a iv-calendar month history of lower dorsum pain and left unilateral L5 nerve harm. His symptoms were astringent, and L5 nervus root infiltration was ineffective and temporary. Preoperative radiographic evaluation indicated L4–five canal stenosis and L5–S1 foraminal stenosis, and thus, L4–L5 posterolateral fusion and L5–S1 transforaminal lumbar interbody fusion (TLIF) were performed using a left total facetectomy with pedicle screws. All pedicle screws were inserted using a gratis-manus technique. Postoperative anteroposterior X-ray imaging showed bilateral S1 screws that were inserted outwardly. Afterwards surgery, preoperative symptoms had disappeared, merely contralateral numbness and hurting in the L5 area appeared on the day of surgery. An L5 nerve rootgraphy was performed using ane.0 ml of the dissimilarity medium iotorolan (Schering). Both rootgraphy and the following computed tomography (CT) revealed that the correct S1 pedicle screw passed diagonally against the pedicle medullary canal toward the far lateral side at an outward bending of fifteen° and penetrated 9.0 mm afar from the anterior cortex of the sacrum. The L5 nerve root was compressed laterally by the perforating S1 screw (Figs.1, 2a, b). Radicular hurting disappeared immediately later infiltration of the L5 spinal nervus with lidocaine (1.v ml of 1 % solution), simply the effectiveness of this treatment was temporary and radicular pain gradually recurred within a few days. Symptoms were transiently improved in a conservative manner by three-time L5 spinal nerve infiltrations and daily oral medication with 180 mg of Loxoprofen. Symptoms remitted within 2 months and had not relapsed at the final follow-up, 1 year after surgery.
Right L5 selective rootgraphy. The outwardly-inserted pedicle spiral laterally compresses the L5 nervus root
Computed tomography (CT) after the right L5 rootgraphy. a In the axial section, the right L5 nervus root is compressed laterally past the perforating S1 screw (white arrow heads). The right s1 pedicle screw passes diagonally confronting the pedicle medullary canal toward the far lateral side, at an outward angle of xv° and penetrates 9.0 mm distant from the anterior cortex of the sacrum. b In the coronal section, the L5 nerve root is compressed laterally by the perforating S1 spiral (white pointer heads)
Case 2
A 62-year-old man was diagnosed with spondylolytic spondylolisthesis and referred to our academy hospital after a 4-month history of lower dorsum hurting and left unilateral L5 nervus harm. His symptoms had gradually increased. Preoperative images indicated a left L5–S1 foraminal stenosis, and L5–S1 TLIF was performed using a left total facetectomy with free mitt-inserted pedicle screws. Immediately after surgery, contralateral lower leg hurting and motor weakness appeared. Postoperative plain X-ray images showed bilateral L5 pedicle screws inserted outwardly. A right L5 selective rootgraphy using one.0 ml of iotorolan indicated that the nerve root was pushed inwardly past a misplaced S1 spiral (Fig.3), and CT later on the right L5 rootgraphy indicated bilateral screws were non inserted through the pedicle and abutted the outer cortex of the vertebral torso (Fig.4a). The right S1 spiral was inserted 17° outwardly and penetrated 8.6 mm afar from the anterior cortex of the sacrum. The right L5 nerve root was encroached upon by the pedicle spiral and the lateral side of the S1 endplate, without any remaining free infinite, effectively crushing the nerve between the screw threads and the sacral body. Postoperative symptoms disappeared temporarily after infiltrating the L5 nerve root with lidocaine (1.v ml of 1 % solution), just completely recurred within an hr. The L5 radicular pain was uncontrollable, even with continuous oral or intravenous injection of opioids. We, therefore, reinserted the misplaced S1 pedicle spiral ane calendar month after initial surgery. Symptoms improved immediately after reinsertion, and there was no relapse during a two-year follow-up (Fig.fourb).
Right L5 selective rootgraphy using 1.0 ml of iotorolan shows that the nervus root is pushed inward by a misplaced S1 spiral
a CT afterwards the right L5 rootgraphy shows that bilateral screws were not inserted through the pedicle and abutted the outer cortex of the vertebral body. The right S1 screw was inserted 17° outwardly and penetrated 8.6 mm distant from the anterior cortex of the sacrum. The correct L5 nerve root is crushed betwixt the pedicle spiral and the lateral side of the S1 endplate, without whatever space to move. b CT subsequently reinsertion indicates that the right spiral was reinserted with four° medial inclination and anchored in the vertebral body
Discussion
Pedicle screw fixation remains the standard method for correction of L5–S1 lumbosacral instability [12–fourteen]. Bicortical or tricortical methods that penetrate the anterior sacral cortex or cranial S1 endplate are reported to provide stronger stability than monocortical methods that merely penetrate the posterior cortex [15–18]. It is generally agreed that medially oriented placement of S1 pedicle screws provides greater stability than either centrally or laterally oriented positions because the hateful bone mineral density in the central region of the sacrum is approximately thirty to sixty % higher than that in the alar region [25, 26]. By contrast, several authors have recommended that placement of S1 pedicle screws in a central position should exist avoided because of the risk this placement carries of harm to the iliac vessels, the sympathetic concatenation, and the lumbosacral torso, which are all close to the sacrum [19–24]. Therefore, from both biomechanical and anatomical points of view, it is recommended that S1 pedicle screws should be inserted inwardly with an acceptable angle reported as about 30° to xl°, near the same equally that of the S1 facet angle [27–31]. However, in general, S1 pedicle screws are inserted from a medial entry point with an outward bending, considering of the prominent dorsal overhang of the posterior iliac crest and paravertebral muscle mass [30, 32–35]. If screws are inserted outwardly, they chance causing an L5 spinal nerve injury, and thus, keen intendance should be taken. The L5 nerve roots are arranged from centrally more cranially to laterally more posteriorly, so damage is anatomically possible. Moreover, Waikakul et al. [36] have reported that nigh one-third of the L4 nervus roots bring together the L5 nerve roots at the level higher up the most anterior role of the sacroiliac articulation, suggesting that an S1 pedicle spiral could injure not only L5, but also L4 nerve roots. Nonetheless, plainly no previously published article has reported L5 or conjoined L4 and L5 nervus root injury induced by an S1 pedicle screw.
To diagnose an L5 nervus injury caused past an S1 pedicle spiral, selective nervus rootgraphy and infiltration of a minimum book of lidocaine were effective. Symptoms were improved past conservative therapy in case ane and neither case relapsed during the follow-upward, and so nosotros believe that reinsertion is not always necessary. We plant a difference in the morphology during L5 rootgraphy. In instance 1, the L5 nerve root coursed outside of the S1 pedicle spiral and there was space lateral to the screw. By contrast, in case 2 the L5 nervus root coursed within of the S1 pedicle screw, crushed betwixt the screw threads and the sacral torso and was restrained from moving considering no space was available. The difference in these findings may be one of the reasons for which the prognosis was different. In the 2 electric current cases, preoperative X-ray imaging did not reveal any severe degenerative scoliosis or rotation of vertebra; therefore, no radiological assist (e.g., fluoroscopy, computed tomography, or navigation) was used. Surgeons should exist alerted to the misplacement of S1 pedicle screws to avert involvement non but inductive to the anteromedial neurovascular tissue, but as well anterolateral to the arrangement of the L5 nerve root. If insertion proves difficult because of overlapping of surrounding muscle or bony tissue, confirmation of an accurate spiral position with some radiological assistance should be made without hesitation to avoid neurovascular complications.
Conflict of interest
None.
References
ane. Bridwell KH, Sedgewick TA, O'Brien MF, Lenke LG, Baldus C. The role of fusion and instrumentation in the handling of degenerative spondylolisthesis with spinal stenosis. J Spinal Disord. 1993;6:461–472. doi: 10.1097/00002517-199306060-00001. [PubMed] [CrossRef] [Google Scholar]
ii. Mardjetko SM, Connolly PJ, Shott S. Degenerative lumbar spondylolisthesis: a meta-analysis of literature 1970–1993. Spine. 1994;19(Suppl):2256–2265. doi: 10.1097/00007632-199410151-00002. [PubMed] [CrossRef] [Google Scholar]
3. Yuan HA, Garfin SR, Dickman CA, Mardjetko SM. A historical cohort report of pedicle screw fixation in thoracic, lumbar, and sacral spinal fusions. Spine. 1994;19(Suppl):2279–2296. doi: ten.1097/00007632-199410151-00005. [PubMed] [CrossRef] [Google Scholar]
iv. Christensen FB. Lumbar spinal fusion. Outcome in relation to surgical methods, pick of implant and postoperative rehabilitation. Acta Orthop Scand Suppl. 2004;75:2–43. doi: 10.1080/03008820410002057. [PubMed] [CrossRef] [Google Scholar]
five. Ledonio CG, Polly DW, Jr, Vitale MG, Wang Q, Richards BS. Pediatric pedicle screws: comparative effectiveness and safe: a systematic literature review from the Scoliosis Inquiry Society and the Pediatric Orthopaedic Society of North America job forcefulness. J Bone Joint Surg Am. 2011;93:1227–1234. doi: ten.2106/JBJS.J.00678. [PubMed] [CrossRef] [Google Scholar]
6. Robertson PA, Plank LD. Prospective accomplice assay of inability reduction with lumbar spinal fusion surgery in community do. J Spinal Disord Tech. 2008;21:235–240. doi: x.1097/BSD.0b013e3180ca712c. [PubMed] [CrossRef] [Google Scholar]
7. Lonstein JE, Denis F, Perra JH, Pinto MR, Smith Dr., Winter RB. Complications associated with pedicle screws. J Os Joint Surg Am. 1999;81:1519–1528. [PubMed] [Google Scholar]
8. Okuda S, Miyauchi A, Oda T, Haku T, Yamamoto T, Iwasaki M. Surgical complications of posterior lumbar interbody fusion with full facetectomy in 251 patients. J Neurosurg Spine. 2006;iv:304–309. doi: 10.3171/spi.2006.iv.4.304. [PubMed] [CrossRef] [Google Scholar]
nine. Rivet DJ, Jeck D, Brennan J, Epstein A, Lauryssen C. Clinical outcomes and complications associated with pedicle screw fixation-augmented lumbar interbody fusion. J Neurosurg Spine. 2004;one:261–266. doi: 10.3171/spi.2004.1.three.0261. [PubMed] [CrossRef] [Google Scholar]
10. Kosmopoulos 5, Schizas C. Pedicle screw placement accuracy: a meta-assay. Spine. 2007;32:E111–E120. doi: 10.1097/01.brs.0000254048.79024.8b. [PubMed] [CrossRef] [Google Scholar]
xi. Gelalis ID, Paschos NK, Pakos EE, Politis AN, Arnaoutoglou CM, Karageorgos Ac, Ploumis A, Xenakis TA. Accuracy of pedicle screw placement: a systematic review of prospective in vivo studies comparing complimentary hand, fluoroscopy guidance and navigation techniques. Eur Spine J. 2012;21:247–255. doi: 10.1007/s00586-011-2011-3. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
12. Jacobs WC, Vreeling A, De Kleuver M. Fusion for low-class adult isthmic spondylolisthesis: a systematic review of the literature. Eur Spine J. 2006;fifteen:391–402. doi: ten.1007/s00586-005-1021-iv. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
13. Zhou ZJ, Zhao FD, Fang XQ, Zhao X, Fan SW. Meta-analysis of instrumented posterior interbody fusion versus instrumented posterolateral fusion in the lumbar spine. J Neurosurg Spine. 2011;15:295–310. doi: 10.3171/2011.4.SPINE10330. [PubMed] [CrossRef] [Google Scholar]
xiv. Schwab FJ, Nazarian DG, Mahmud F, Michelsen CB. Effects of spinal instrumentation on fusion of the lumbosacral spine. Spine. 1995;xx:2023–2028. doi: 10.1097/00007632-199509150-00014. [PubMed] [CrossRef] [Google Scholar]
15. McCord DH, Cunningham BW, Shono Y, Myers JJ, McAfee PC. Biomechanical analysis of lumbosacral fixation. Spine. 1992;17:S235–S243. doi: ten.1097/00007632-199208001-00004. [PubMed] [CrossRef] [Google Scholar]
16. von Strempel A, Trenkmann S, Krönauer I, Kirsch Fifty, Sukopp C. The stability of bone screws in the bone sacrum. Eur Spine J. 1998;seven:313–320. doi: 10.1007/s005860050081. [PMC costless commodity] [PubMed] [CrossRef] [Google Scholar]
17. Lehman RA, Jr, Kuklo TR, Belmont PJ, Jr, Andersen RC, Polly DW., Jr Advantage of pedicle screw fixation directed into the apex of the sacral promontory over bicortical fixation: a biomechanical assay. Spine. 2002;27:806–811. doi: 10.1097/00007632-200204150-00006. [PubMed] [CrossRef] [Google Scholar]
eighteen. Orita S, Ohtori South, Eguchi Y, Kamoda H, Arai G, Ishikawa T, Miyagi M, Inoue G, Ochiai N, Kishida S, Takaso M, Aoki Y, Takahashi K. Radiographic evaluation of monocortical versus tricortical buy approaches in lumbosacral fixation with sacral pedicle screws: a prospective study of ninety consecutive patients. Spine. 2010;35:E1230–E1237. doi: 10.1097/BRS.0b013e3181e5092c. [PubMed] [CrossRef] [Google Scholar]
19. Ergur I, Akcali O, Kiray A, Kosay C, Tayefi H. The role of fusion and instrumentation in the handling of degenerative spondylolisthesis with spinal stenosis. Eur Spine J. 2007;16:1519–1523. doi: ten.1007/s00586-007-0326-x. [PMC gratis commodity] [PubMed] [CrossRef] [Google Scholar]
20. Esses SI, Botsford DJ, Huler RJ, Rauschning W. Surgical anatomy of the sacrum: a guide for rational screw fixation. Spine. 1991;16:S283–S288. doi: x.1097/00007632-199106001-00021. [PubMed] [CrossRef] [Google Scholar]
21. Licht NJ, Rowe DE, Ross LM. Pitfalls of pedicle screw fixation in the sacrum. Spine. 1992;17:892–896. doi: ten.1097/00007632-199208000-00006. [PubMed] [CrossRef] [Google Scholar]
22. Mirkovic S, Abitbol JJ, Steinman J, Edwards CC, Schaffler 1000, Massie J, Garfin SR. Anatomic consideration for sacral screw placement. Spine. 1991;16:S289–S294. doi: x.1097/00007632-199106001-00022. [PubMed] [CrossRef] [Google Scholar]
23. Morse BJ, Ebraheim NA, Jackson WT. Preoperative CT conclusion of angles for sacral screw placement. Spine. 1994;19:604–607. doi: 10.1097/00007632-199403000-00017. [PubMed] [CrossRef] [Google Scholar]
24. Xu R, Ebraheim NA, Yeasting RA, Wong FY, Jackson WT. Morphometric evaluation of the showtime sacral vertebra and the projection of its pedicle on the posterior aspect of the sacrum. Spine. 1995;twenty:936–940. doi: 10.1097/00007632-199504150-00010. [PubMed] [CrossRef] [Google Scholar]
25. Smith SA, Abitbol JJ, Carlson GD, Anderson DR, Taggart KW, Garfin SR. The effects of depth of penetration, spiral orientation, and bone density on sacral screw fixation. Spine. 1993;18:1006–1010. doi: x.1097/00007632-199306150-00009. [PubMed] [CrossRef] [Google Scholar]
26. Zheng Y, Lu WW, Zhu Q, Qin Fifty, Zhong S, Leong JC. Variation in bone mineral density of the sacrum in young adults and its significance for sacral fixation. Spine. 2000;25:353–357. doi: 10.1097/00007632-200002010-00016. [PubMed] [CrossRef] [Google Scholar]
27. Arman C, Naderi Southward, Kiray A, Aksu FT, Yilmaz HS, Tetik S, Korman E. The human sacrum and rubber approaches for screw placement. J Clin Neurosci. 2009;16:1046–1049. doi: 10.1016/j.jocn.2008.07.081. [PubMed] [CrossRef] [Google Scholar]
28. Okutan O, Kaptanoglu E, Solaroglu I, Beskonakli E, Tekdemir I. Determination of the length of anteromedial screw trajectory by measuring interforaminal distance in the first sacral vertebra. Spine. 2004;29:1608–1611. doi: 10.1097/01.BRS.0000132309.17578.B0. [PubMed] [CrossRef] [Google Scholar]
29. Robertson PA, Stewart NR. The radiologic anatomy of the lumbar and lumbosacral pedicles. Spine. 2000;25:709–715. doi: 10.1097/00007632-200003150-00010. [PubMed] [CrossRef] [Google Scholar]
30. de Peretti F, Argenson C, Bourgeon A, Omar F, Eude P, Aboulker C. Anatomic and experimental basis for the insertion of a screw at the offset sacral vertebra. Surg Radiol Anat. 1991;xiii:133–137. doi: x.1007/BF01623887. [PubMed] [CrossRef] [Google Scholar]
31. Louis R. Fusion of the lumbar and sacral spine by internal fixation with screw plates with screw plates. Clin Orthop Relat Res. 1986;203:18–33. [PubMed] [Google Scholar]
32. Robertson PA, Plank LD. Pedicle screw placement at the sacrum: anatomical characterization and limitations at S1. J Spinal Disord. 1999;12:227–233. [PubMed] [Google Scholar]
33. Kaptanoglu E, Okutan O, Tekdemir I, Beskonakli E, Deda H. Closed posterior superior iliac spine impeding pediculocorporeal Due south-1 screw insertion. J Neurosurg. 2003;99(2 Suppl):29–34. [PubMed] [Google Scholar]
34. Asher MA, Strippgen We. Antrhopometric studies of the human sacrum relating to dorsal transsacral implant. Clin Orthop Relat Res. 1986;203:58–62. [PubMed] [Google Scholar]
35. Xu R, Ebraheim NA, Mohamed A, el-Gamal H, Yeasting RA. Anatomic considerations for dorsal sacral plate-screw placement. J Spinal Disord. 1995;8:352–356. [PubMed] [Google Scholar]
36. Waikakul S, Chandraphak S, Sangthongsil P. Anatomy of L4 to S3 nervus roots. J Orthop Surg (Hong Kong) 2010;18:352–355. [PubMed] [Google Scholar]
Articles from European Spine Journal are provided here courtesy of Springer-Verlag
0 Response to "Nerve Pinched From Fusion Broken Hardware"
Post a Comment