An Official publication of The Asian Congress of Neurological Surgeons (AsianCNS)

Search Article
Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Advertise Subscribe Contacts Login  Facebook Tweeter
  Users Online: 1126 Home Print this page Email this page Small font sizeDefault font sizeIncrease font size  

   Table of Contents      
ORIGINAL ARTICLE
Year : 2015  |  Volume : 10  |  Issue : 3  |  Page : 166-172

Analysis of 1014 consecutive operative cases to determine the utility of intraoperative neurophysiological data


Department of Neurosurgery, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania, USA

Date of Web Publication22-Jul-2015

Correspondence Address:
Namath Syed Hussain
Department of Neurosurgery, Penn State Milton S. Hershey Medical Center, 30 Hope Drive, EC110, Hershey, Pennsylvania 17033
USA
Login to access the Email id

Source of Support: Nil, Conflict of Interest: None declared.


DOI: 10.4103/1793-5482.161197

Rights and Permissions
  Abstract 

Introduction: Intraoperative neurophysiological monitoring (IOM) during neurosurgical procedures has become the standard of care at tertiary care medical centers. While prospective data regarding the clinical utility of IOM are conspicuously lacking, retrospective analyses continue to provide useful information regarding surgeon responses to reported waveform changes.
Methods: Data regarding clinical presentation, operative course, IOM, and postoperative neurological examination were compiled from a database of 1014 cranial and spinal surgical cases at a tertiary care medical center from 2005 to 2011. IOM modalities utilized included somatosensory evoked potentials, transcranial motor evoked potentials, pedicle screw stimulation, and electromyography. Surgeon responses to changes in IOM waveforms were recorded.
Results: Changes in IOM waveforms indicating potential injury were present in 87 of 1014 cases (8.6%). In 23 of the 87 cases (26.4%), the surgeon responded by repositioning the patient (n = 12), repositioning retractors (n = 1) or implanted instrumentation (n = 9), or by stopping surgery (n = 1). Loss of IOM waveforms predicted postoperative neurological deficit in 10 cases (11.5% of cases with IOM changes).
Conclusions: In the largest IOM series to date, we report that the surgeon responded by appropriate interventions in over 25% of cases during which there were IOM indicators of potential harm to neural structures. Prospective studies remain to be undertaken to adequately evaluate the utility of IOM in changing surgeon behavior. Our data is in agreement with previous observations in indicating a trend that supports the continued use of IOM.

Keywords: Intraoperative monitoring, postoperative deficits, quality, surgical planning, waveform changes


How to cite this article:
Hussain NS. Analysis of 1014 consecutive operative cases to determine the utility of intraoperative neurophysiological data. Asian J Neurosurg 2015;10:166-72

How to cite this URL:
Hussain NS. Analysis of 1014 consecutive operative cases to determine the utility of intraoperative neurophysiological data. Asian J Neurosurg [serial online] 2015 [cited 2021 Jun 22];10:166-72. Available from: https://www.asianjns.org/text.asp?2015/10/3/166/161197


  Introduction Top


Intraoperative neurophysiological monitoring (IOM) during neurosurgical procedures has become the standard of care at tertiary care medical centers.[1][2][3][4][5][6] As studies have been published with regard to its utility and while it has be adopted as an almost universal adjunct to the neurosurgeon’s operative equipment, there has not been any report in the literature describing detailed surgical experience with IOM, correlating monitoring changes with surgeon responses and actions in the operating room and patient postoperative neurological deficits.

Spinal and cranial decompression procedures are among the most common procedures in most clinical practices; however, in the recent years, due to surgeon-industry collaborations, more advanced equipment for surgical reconstruction has increased the utilization of permanently implanted hardware.[1],[6][7][8][9][10][11][12],[13] This practice pattern introduces risks to the patient and must be done in the safest manner possible. The appropriate neuromonitoring adjuncts must be utilized when needed to improve safety.[2],[4],[5],[14][15][16][17][18] Even though the IOM technologist and the consulting neurologist reading the waveform changes appear to be the ones most knowledgeable with the respect to the IOM technology and machinery, it is critical for the surgeon to be up-to-date regarding the technology as they are the ones most directly making intraoperative decisions based on these IOM waveform changes that can permanently affect patients. Only the surgeon is perfectly privy and poised to make the most adequate decision with respect to continuing with surgery, changing the operative plan, or aborting.[19]

While most surgeons are aware of these IOM tools and their medicolegal fallout and implications, many do not have a clear understanding of what actions to take in the event of a monitoring change and how likely these changes will signal a postoperative deficit since no clinical study has been conducted to examine these waveform changes in a rigorous manner. Our hypothesis was that IOM waveform changes do predict neurological deficit and that surgeon actions in response to these alerts can help to reduce postoperative deficits. Our study aims to describe our surgical experience over a 7 year period including intraoperative monitoring alerts along with surgeon responses to these alerts coupled with any changes in the patient’s clinical exam postoperatively.


  Methods Top


Data regarding patient clinical presentation and neurological examination, operative course, IOM modalities used, IOM waveform baseline abnormalities and changes, alerts given to the surgeon by the technologist, surgeon responses to these alerts, surgeon actions in response to these alerts, and the postoperative patient neurological examination were compiled from a database of 1014 cranial and spinal surgical cases at a single institution from 2005 to 2011. IOM modalities utilized included somatosensory evoked potentials (SSEPs), transcranial motor evoked potentials (MEPs), dermatomal evoked potentials (DEPs), visual evoked responses (VERs), pedicle screw stimulation, and electromyography (EMG) [Figure 1][Figure 2][Figure 3][Figure 4][Figure 5][Figure 6]. The data were acquired, displayed in real time, and stored digitally using Cascade® software on a customized desktop personal computer. Surgeon responses to changes in IOM waveforms were recorded by the monitoring technologist and maintained in our clinical database in a prospective fashion.
Figure 1: Intraoperative neurophysiological monitoring waveforms monitored including somatosensory evoked potentials and motor evoked potentials

Click here to view
Figure 2: Ulnar nerve waveform loss with central line placement

Click here to view
Figure 3: (a and b) Ulnar nerve waveform loss with axillary retractor placement and waveform return with retractor removal

Click here to view
Figure 4: Ulnar nerve waveform loss during posterior cervical decompression

Click here to view
Figure 5: L5 nerve changes during vertebral body cage implantation

Click here to view
Figure 6: Electromyography changes during L5-S1 interbody graft placement

Click here to view


Waveform evaluation included a quantitative and qualitative analysis of variability, morphology, latency, and amplitude of waveforms and their relationship to the anesthetic regimen, specifically the minimum alveolar concentration (MAC) of volatile inhalant agent along with the stage of surgery and any reported surgeon actions. In evaluating SSEP waveforms, a decrease in amplitude of 50% or increase in latency of 10% was considered to be indicative of a significant change that may indicate damage to neural structures. In our assessment of MEPs, DEPs, and VERs, we reported a change as a decrease in amplitude of 80%. Intraoperative EMG consists of spontaneous EMG obtained by placing electrodes directly in muscles and triggered EMG or pedicle screw stimulation. Spikes, bursts, and trains of EMG activity were recorded, with trains being of highest concern for nerve injury. A Spearman’s rank correlation coefficient was calculated for each modality, as we are comparing nonparametric data (presence or lack of deficits being binary data). Using several descriptive cases, we illustrate how intraoperative monitoring can be utilized to the neurosurgeon’s advantage to decrease patient and surgery-related morbidity.

In terms of anesthetic management, the volatile agent in approximately two-thirds of the cases was sevoflurane. In most of the remaining cases desflurane was utilized and in a very few cases isoflurane was used. MAC values used for desflurane, sevoflurane, and isoflurane were 6.5, 2.2, and 1.1% respectively. The status of neuromuscular blocking was monitored by repetitive train-of-four stimulation of the ulnar nerve with recording from the first dorsal interosseus muscle. Narcotics were generally administered as a continuous infusion, although occasionally as a bolus. Sufentanil was the agent most commonly used, followed by fentanyl. In several cases, a total intravenous anesthetic protocol was used, consisting of propofol and sufentanil infusions. In most cases, the propofol infusion was 100 μg/kg/min.

Statistical analysis was performed with StatTools add-in statistical package for Microsoft Excel 2003. P < 0.05 was used to determine the significance. Spearman rank correlation coefficient was used to calculate correlations.


  Results Top


There were no anesthesia-related intraoperative complications. The most common procedures performed were posterior lumbar fusion (n = 413), anterior cervical discectomy and fusion (n = 135), posterior cervical fusion (n = 131), and posterior thoracic fusion (n = 111). Quantitatively recorded changes in IOM waveforms indicating potential injury were present in 87 of 1014 cases (8.6%). The relationship between the degree of amplitude loss or latency increase and presence of postoperative deficits was not significant (r = 0.045, P = 0.15). No one modality predicted postoperative deficits better than another. Representative screenshots from the Cascade® software platform of waveform changes are shown in [Figure 2][Figure 3][Figure 4][Figure 5][Figure 6]. Examples that involved waveform changes that normalized after repositioning are shown. In 23 of the 87 cases (26.4%), the surgeon responded [Table 1] by repositioning the patient (n = 12), repositioning retractors (n = 1) or implanted instrumentation (n = 9), or by stopping surgery (n = 1) [Table 2]. In all cases where the surgeon repositioned retractors or the patient, there were no sustained postoperative deficits. Four patients sustained deficits despite surgeon action [Table 1]. Loss of IOM waveforms predicted postoperative neurological deficit in 10 cases (11.5% of cases with IOM changes). Thus, in 11.5% of cases where IOM changes were present, the patient sustained a postoperative new neurological deficit. There was only one instance of a postoperative deficit when there were no IOM alerts noted. We did not have any instance of permanent deficits when repositioning retractors (n = 1), or implanted instrumentation (n = 9), or by stopping surgery (n = 1). An example that involved waveform changes that normalized after repositioning is shown [Figure 3].
Table 1: 2×2 table showing breakdown of new deficits and surgeon responses in the subset of 87cases with waveform changes

Click here to view
Table 2: Waveform changes noted during the study


Click here to view



  Cases Top


Case presentation 1: Normal IOM waveforms [Figure 1].

Case presentation 2: Ulnar nerve waveform loss with placement of central line [Figure 2].

Case presentation 3: Ulnar nerve waveform loss with placement of axillary retractor and regain of waveform with retractor repositioning [[Figures 3]a, 3b].

Case presentation 4: Ulnar nerve waveform loss during posterior cervical decompression [Figure 4].

Case presentation 5: Waveform changes with L5 cage placement [Figure 5].

Case presentation 6: Free-run EMG changes noted during L5-S1 instrumentation [Figure 6].


  Discussion Top


Minimally-invasive neurosurgical techniques have provided newer approaches that have led to better outcomes and are the preferred method for both cranial and spinal surgery over the past decade.[20],[21] Several studies have borne out the utility of IOM by looking at waveform changes and whether patients suffer from deficits postoperatively.[2],[3],[18],[22][23][24][25][26][27],[34]

Somatosensory evoked potentials monitor the dorsal column-medial lemniscus pathway by recording specifically from the median and ulnar nerves in the upper extremities and the posterior tibial nerve and peroneal nerves in the lower extremities. A decrease in amplitude of 50% or increase in latency of 10% is considered to be indicative of a significant change that may indicate damage to neural structures.[28],[29],[30] MEPs provide monitoring of the corticospinal tract. In the past, a clinical examination was required to attain this type of information, and an intraoperative wake-up test was often utilized. There are two usual methods of recording MEPs. They can be obtained transcranially as we did or via D-wave monitoring directly at the spinal cord level. MEPs vary in their interpretation. Some studies have used an all-or-nothing amplitude threshold while others have employed specific morphology criteria.[31]

Our study provides convincing evidence of that utility of IOM. Changes in IOM waveforms indicating potential injury occurred in 8.6% of cases in our large series. A unique aspect of our study is that we recorded surgeon responses to IOM waveform changes. In 23 of the 87 cases (26.4%), the surgeon responded with some change in the intraoperative plan [Table 1], meaning they took some action in response to the waveform changes. Loss of IOM waveforms predicted postoperative neurological deficit in 10 cases (11.5% of cases with IOM changes), making this a useful adjunct in neurosurgical procedures.

Raynor et al. have reported on the largest IOM data series to date examining 12,375 spinal surgical procedures.[16] They identified 386 (3.1%) patients with loss/degradation of IOM waveforms. On examination of surgeon actions and their sequelae, they found that in 93.3% of patients with waveform changes, intervention by the surgeon based on this IOM information led to waveform recovery and no neurological deficits after surgery. Reduction from a potential (worst-case scenario) 3.1% (386) of patients with significant change in IOM waveforms to a permanent postoperative neurological deficit rate of 0.12% (15) patients was achieved (P < 0.0001), thus confirming utility of IOM. These results are in line with ours except for their very small deficit rate that may be a result of how they defined deficit, which was not explained in their methods. Our definition was any change in motor power on the traditional 5 point scale.

In a very large study with similar patient numbers (1121 patients) as ours, Schwartz et al. found that 38 (3.4%) of patients had waveform changes.[32] Of those 38 patients, 17 showed MEP loss of over 65% without SSEP changes. In nine of the 38 patients, the signal change was related to hypotension and was corrected intraoperatively. In the remaining 29 patients, waveform loss was directly temporally related to a surgical maneuver. Three alerts occurred following segmental vessel clamping, and the remaining 26 alerts were related to instrumentation implantation and deformity correction. In total 9 (35%) of these 26 patients with an instrumentation-related alert, or 0.8% of the total cohort, awoke from surgery with a transient motor and/or sensory deficit with seven having motor and two having sensory deficits. SSEPs failed to identify a motor deficit in four of the seven patients with a confirmed motor deficit. An additional finding of the study was that changes in SSEPs lagged behind changes in MEPs by an average of 5 min. With an appropriate response to the alert, the deficits in all nine patients resolved within 3 months.

Hilibrand et al. reported on another large cohort of 427 patients, 12 of whom demonstrated substantial or complete loss of amplitude of MEPs.[33] Ten of the 12 patients had complete resolution of the waveform loss with the surgeon intraoperative intervention, whereas the remaining two awoke with a new motor deficit. SSEP changes lagged behind MEP changes by half an hour. According to their data, MEPs were 100% sensitive and 100% specific, whereas SSEPs were 25% sensitive and 100% specific. They found that transient sensory deficits when they do occur most likely represent mild neuropraxia that usually resolve, which agrees with the findings in our operative database.

The literature contains several studies documenting the utility of IOM, but there has been no previous study that documents both surgeon responses and deficits postoperatively such as ours. We hope that this finding may convince more surgeons that IOM has utility, and that waveform changes should not be overlooked when IOM is used. These findings also provide rigorous documentation with no patients lost to follow-up that may provide the basis for further research endeavors that may explore other aspects of how monitoring changes, surgeon responses, and patient deficits interplay with one another. More study is needed to obtain more quantitative data in terms of how long monitoring changes occurred before surgeons took action and what degree of monitoring changes were most likely or sufficient induce surgeon response or result in a new postoperative deficit.


  Conclusions Top


Intraoperative neurophysiological monitoring is an effective adjunct to the neurosurgeon’s armamentarium that may be particularly helpful when confronted with pathology near eloquent neural tissue. With improved IOM platforms, new minimally-invasive surgical techniques can help treat patients while improving the safety profile of our treatment options. In the largest comprehensive clinical IOM series to date that includes patients’ preoperative and postoperative exam, IOM alerts, and surgeon actions, we report that the surgeon responded by appropriate interventions in over 25% of cases during which there were IOM indicators of potential harm to nearby critical neural structures. Further prospective studies remain to be undertaken to adequately evaluate the utility of IOM in modifying and changing surgeon behavior. Further refinements in surgical technique can be recommended with this type of intraoperative data. Ultimately, patient safety and satisfaction will drive adoption of these data sets into clinical practice utilization and oversight. Our data are in agreement with previous studies indicating a trend that supports the continued use of IOM.



 
  References Top

1.
Calancie B, Harris W, Broton JG, Alexeeva N, Green BA. “Threshold-level” multipulse transcranial electrical stimulation of motor cortex for intraoperative monitoring of spinal motor tracts: Description of method and comparison to somatosensory evoked potential monitoring. J Neurosurg 1998;88:457-70.  Back to cited text no. 1
    
2.
Cho KJ, Suk SI, Park SR, Kim JH, Kim SS, Choi WK, et al. Complications in posterior fusion and instrumentation for degenerative lumbar scoliosis. Spine (Phila Pa 1976) 2007;32:2232-7.  Back to cited text no. 2
    
3.
Chung I, Glow JA, Dimopoulos V, Walid MS, Smisson HF, Johnston KW, et al. Upper-limb somatosensory evoked potential monitoring in lumbosacral spine surgery: A prognostic marker for position-related ulnar nerve injury. Spine J 2009;9:287-95.  Back to cited text no. 3
    
4.
Dekutoski MB, Norvell DC, Dettori JR, Fehlings MG, Chapman JR. Surgeon perceptions and reported complications in spine surgery. Spine (Phila Pa 1976) 2010;35:S9-21.  Back to cited text no. 4
    
5.
Deletis V, Sala F. Intraoperative neurophysiological monitoring of the spinal cord during spinal cord and spine surgery: A review focus on the corticospinal tracts. Clin Neurophysiol 2008;119:248-64.  Back to cited text no. 5
    
6.
Eggspuehler A, Sutter MA, Grob D, Jeszenszky D, Porchet F, Dvorak J. Multimodal intraoperative monitoring (MIOM) during cervical spine surgical procedures in 246 patients. Eur Spine J 2007;16 Suppl 2:S209-15.  Back to cited text no. 6
    
7.
Fan D, Schwartz DM, Vaccaro AR, Hilibrand AS, Albert TJ. Intraoperative neurophysiologic detection of iatrogenic C5 nerve root injury during laminectomy for cervical compression myelopathy. Spine (Phila Pa 1976) 2002;27:2499-502.  Back to cited text no. 7
    
8.
Fehlings MG, Brodke DS, Norvell DC, Dettori JR. The evidence for intraoperative neurophysiological monitoring in spine surgery: Does it make a difference? Spine (Phila Pa 1976) 2010;35:S37-46.  Back to cited text no. 8
    
9.
Guérit JM, Verhelst R, Rubay J, Khoury G, Matta A, Dion R. Multilevel somatosensory evoked potentials (SEPs) for spinal cord monitoring in descending thoracic and thoraco-abdominal aortic surgery. Eur J Cardiothorac Surg 1996;10:93-103.  Back to cited text no. 9
    
10.
Guerit JM, Witdoeckt C, Verhelst R, Matta AJ, Jacquet LM, Dion RA. Sensitivity, specificity, and surgical impact of somatosensory evoked potentials in descending aorta surgery. Ann Thorac Surg 1999;67:1943-6.  Back to cited text no. 10
    
11.
Hilibrand AS, Schwartz DM, Sethuraman V, Vaccaro AR, Albert TJ. Comparison of transcranial electric motor and somatosensory evoked potential monitoring during cervical spine surgery. J Bone Joint Surg Am 2004;86-A: 1248-53.  Back to cited text no. 11
    
12.
Hussain NS, Perez-Cruet MJ. Complication management with minimally invasive spine procedures. Neurosurg Focus 2011;31:E2.  Back to cited text no. 12
    
13.
Isaacs RE, Hyde J, Goodrich JA, Rodgers WB, Phillips FM. A prospective, nonrandomized, multicenter evaluation of extreme lateral interbody fusion for the treatment of adult degenerative scoliosis: Perioperative outcomes and complications. Spine (Phila Pa 1976) 2010;35:S322-30.  Back to cited text no. 13
    
14.
Ito Z, Matsuyama Y, Shinomiya K, Ando M, Kawabata S, Kanchiku T, et al. Usefulness of multi-channels in intraoperative spinal cord monitoring: Multi-center study by the Monitoring Committee of the Japanese Society for Spine Surgery and related research. Eur Spine J 2013;22:1891-6.  Back to cited text no. 14
    
15.
Jarvis JG, Strantzas S, Lipkus M, Holmes LM, Dear T, Magana S, et al. Responding to neuromonitoring changes in 3-column posterior spinal osteotomies for rigid pediatric spinal deformities. Spine (Phila Pa 1976) 2013;38:E493-503.  Back to cited text no. 15
    
16.
Jellish WS, Sherazee G, Patel J, Cunanan R, Steele J, Garibashvilli K, et al. Somatosensory evoked potentials help prevent positioning-related brachial plexus injury during skull base surgery. Otolaryngol Head Neck Surg 2013;149:168-73.  Back to cited text no. 16
    
17.
Lorenzini NA, Poterack KA. Somatosensory evoked potentials are not a sensitive indicator of potential positioning injury in the prone patient. J Clin Monit 1996;12:171-6.  Back to cited text no. 17
    
18.
Luk KD, Hu Y, Wong YW, Cheung KM. Evaluation of various evoked potential techniques for spinal cord monitoring during scoliosis surgery. Spine (Phila Pa 1976) 2001;26:1772-7.  Back to cited text no. 18
    
19.
Mardjetko SM, Connolly PJ, Shott S. Degenerative lumbar spondylolisthesis. A meta-analysis of literature 1970-1993. Spine (Phila Pa 1976) 1994;19 20 Suppl: 2256S-65.  Back to cited text no. 19
    
20.
McAfee PC, Phillips FM, Andersson G, Buvenenadran A, Kim CW, Lauryssen C, et al. Minimally invasive spine surgery. Spine (Phila Pa 1976) 2010;35:S271-3.  Back to cited text no. 20
    
21.
Novak K, Widhalm G, de Camargo AB, Perin N, Jallo G, Knosp E, et al. The value of intraoperative motor evoked potential monitoring during surgical intervention for thoracic idiopathic spinal cord herniation. J Neurosurg Spine 2012;16:114-26.  Back to cited text no. 21
    
22.
Pastorelli F, Di Silvestre M, Plasmati R, Michelucci R, Greggi T, Morigi A, et al. The prevention of neural complications in the surgical treatment of scoliosis: The role of the neurophysiological intraoperative monitoring. Eur Spine J 2011;20 Suppl 1:S105-14.  Back to cited text no. 22
    
23.
Raynor BL, Bright JD, Lenke LG, Rahman RK, Bridwell KH, Riew KD, et al. Significant change or loss of intraoperative monitoring data: A 25-year experience in 12,375 spinal surgeries. Spine (Phila Pa 1976) 2013;38:E101-8.  Back to cited text no. 23
    
24.
Robertazzi RR, Cunningham JN Jr. Monitoring of somatosensory evoked potentials: A primer on the intraoperative detection of spinal cord ischemia during aortic reconstructive surgery. Semin Thorac Cardiovasc Surg 1998;10:11-7.  Back to cited text no. 24
    
25.
Robertazzi RR, Cunningham JN Jr. Intraoperative adjuncts of spinal cord protection. Semin Thorac Cardiovasc Surg 1998;10:29-34.  Back to cited text no. 25
    
26.
Rodgers WB, Gerber EJ, Patterson J. Intraoperative and early postoperative complications in extreme lateral interbody fusion: An analysis of 600 cases. Spine (Phila Pa 1976) 2011;36:26-32.  Back to cited text no. 26
    
27.
Rousseau MA, Lazennec JY, Bass EC, Saillant G. Predictors of outcomes after posterior decompression and fusion in degenerative spondylolisthesis. Eur Spine J 2005;14:55-60.  Back to cited text no. 27
    
28.
Sala F, Lanteri P, Bricolo A. Motor evoked potential monitoring for spinal cord and brain stem surgery. Adv Tech Stand Neurosurg 2004;29:133-69.  Back to cited text no. 28
    
29.
Schwartz DM, Auerbach JD, Dormans JP, Flynn J, Drummond DS, Bowe JA, et al. Neurophysiological detection of impending spinal cord injury during scoliosis surgery. J Bone Joint Surg Am 2007;89:2440-9.  Back to cited text no. 29
    
30.
Seyal M, Mull B. Mechanisms of signal change during intraoperative somatosensory evoked potential monitoring of the spinal cord. J Clin Neurophysiol 2002;19:409-15.  Back to cited text no. 30
    
31.
Stecker MM, Robertshaw J. Factors affecting reliability of interpretations of intra-operative evoked potentials. J Clin Monit Comput 2006;20:47-55.  Back to cited text no. 31
    
32.
Thirumala PD, Kodavatiganti HS, Habeych M, Wichman K, Chang YF, Gardner P, et al. Value of multimodality monitoring using brainstem auditory evoked potentials and somatosensory evoked potentials in endoscopic endonasal surgery. Neurol Res 2013;35:622-30.  Back to cited text no. 32
    
33.
Tormenti MJ, Maserati MB, Bonfield CM, Okonkwo DO, Kanter AS. Complications and radiographic correction in adult scoliosis following combined transpsoas extreme lateral interbody fusion and posterior pedicle screw instrumentation. Neurosurg Focus 2010;28:E7.  Back to cited text no. 33
    
34.
Tormenti MJ, Maserati MB, Bonfield CM, Gerszten PC, Moossy JJ, Kanter AS, et al. Perioperative surgical complications of transforaminal lumbar interbody fusion: A single-center experience. J Neurosurg Spine 2012;16:44-50.  Back to cited text no. 34
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
 
 
    Tables

  [Table 1], [Table 2]


This article has been cited by
1 Intraoperative Neuromonitoring and Lumbar Spinal Instrumentation: Indications and Utility
Ryan C. Hofler,Richard G. Fessler
The Neurodiagnostic Journal. 2021; 61(1): 2
[Pubmed] | [DOI]
2 Position-related neurovascular injuries detected by intraoperative monitoring
Shaila Gowda
Indian Spine Journal. 2021; 4(1): 113
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
<
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)  

 
  In this article
   Abstract
  Introduction
  Methods
  Results
  Cases
  Discussion
  Conclusions
   References
   Article Figures
   Article Tables

 Article Access Statistics
    Viewed1577    
    Printed6    
    Emailed0    
    PDF Downloaded202    
    Comments [Add]    
    Cited by others 2    

Recommend this journal