The Impact of Intraoperative Image-Guidance Modalities and Neurophysiologic Monitoring in the Safety of Sacroiliac Fusions.

STUDY DESIGN: Retrospective observational cohort. OBJECTIVE: A review of efficiency and safety of fluoroscopy and stereotactic navigation system for minimally invasive (MIS) Sacroiliac (SI) fusion through a lateral technique. METHODS: Retrospective analysis of an observational cohort of 96 patients greater than 18 years old, that underwent MIS SI fusion guided by fluoroscopy or navigation between January 2013 and April 2020 with a minimum of 3 months follow-up. Intraoperative neuromonitoring (IONM) with a variable combination of electromyography (EMG), somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) was also utilized. RESULTS: The overall complication rate in the study was 9.4%, and there was no difference between the fluoroscopy (10.1%), and navigation groups (8%). Neurological complication rate was 2.1%, without a significant difference between both intraoperative guidance modality groups (p = 0.227). There was a significant difference between the modalities of IONM used and the occurrence of neurological injury (p = 0.01).The 2 patients who had a neurological complication postoperatively were monitored only with EMG and SSEP, but none of the patients (n = 76) in which MEPs were utilized had neurologic complication. The mean pain improvement 3 months after surgery was greater in the navigation group (2.44 ± 2.72), but was not statistically different than the improvement in the fluoroscopy group (1.90 ± 2.07) (p = 0.301). CONCLUSIONS: No difference in the safety of the procedure was found between the fluoroscopy and the stereotactic navigation techniques. The contribution of the IONM to the safety of SI fusions could not be determined, but the data indicates that MEPs provide the highest level of sensitivity.

Independent Predictors of Revision Lumbar Fusion Outcomes and the Impact of Spine Surgeon Variability: Does It Matter Whether the Primary Surgeon Revises?

BACKGROUND: There is a paucity of information regarding treatment strategies and variables affecting outcomes of revision lumbar fusions. OBJECTIVE: To evaluate the influence of primary vs different surgeon on functional outcomes of revisions. METHODS: All elective lumbar fusion revisions, March 2018 to August 2019, were retrospectively categorized as performed by the same or different surgeon who performed the primary surgery. Oswestry Disability Index (ODI) and clinical variables were collected. Multiple logistic regression identified multivariable-adjusted odds ratio (OR) of independent variables analyzed. RESULTS: Of the 130 cases, 117 (90%) had complete data. There was a slight difference in age in the same (median: 59; interquartile range [IQR], 54-66) and different surgeon (median: 67; IQR, 56-72) groups (P = .02); all other demographic variables were not significantly different (P > .05). Revision surgery with a different surgeon had an ODI improvement (median: 8; IQR, 2-14) greater than revisions performed by the same surgeon (median: 1.5; IQR, -3 to 10) (P < .01). Revisions who achieved minimum clinically important difference (MCID) performed by different surgeon (59.7%) were also significantly greater than the ones performed by the same surgeon (40%) (P = .042). Multivariate analysis demonstrated that a different surgeon revising (OR, 2.37; [CI]: 1.007-5.575, P = .04) was an independent predictor of MCID achievement, each additional 2 years beyond the last surgery conferred a 2.38 ([CI]: 1.36-4.14, P < .01) times greater odds of MCID achievement, and the anterior lumbar interbody fusion approach decreased the chance of achieving MCID (OR, 0.19; [CI]: 0.04-0.861, P = .03). CONCLUSION: All revision lumbar spinal fusion approaches may not achieve the same outcomes. This analysis suggests that revision surgeries may have better outcomes when performed by a different surgeon.

The Impact of Incorporating Evidence-Based Guidelines for Lumbar Fusion Surgery in Neurosurgical Resident Education.

BACKGROUND: Instrumented fusion procedures are essential in the treatment of degenerative lumbar spine disease to alleviate pain and improve neurological function, but they are being performed with increasing incidence and variability. We implemented a training module for neurosurgery residents that is based on evidence-based criteria for lumbar fusion surgery and measured its effectiveness in residents' decision making regarding whether patients should or should not undergo instrumented fusion. METHODS: The study design was a pretest versus posttest experiment conducted from September 2019 until July 2020 to measure improvement after formalized instruction on evidence-based guidelines. Neurosurgery residents of all training levels at our institution participated. A test was administered at the beginning of each academic year. The highest possible score was 18 points in each pretest and posttest. RESULTS: There was a general trend of test score improvement across all levels of training with a greater degree of change for participants with lower compared with higher pretest scores, indicating a possible ceiling effect. Paired t test demonstrated an overall mean score increase of 2 points (P < 0.0001), equivalent to an 11.11% increase (P < 0.0001). Stratified by training group, mean absolute change in test score was 2 (P = 0.0217), 1.67 (P = 0.0108), and 2.25 (P = 0.0173) points for junior, midlevel, and senior training groups, respectively. CONCLUSIONS: Incorporating a targeted evidence-based learning module for lumbar spine fusion surgery can improve neurosurgery residents' clinical decision making toward a more uniform practice supported by published data.

Anatomical and developmental aspects of iatrogenic injury to the right recurrent laryngeal nerve in surgical resections of substernal goiter.

Thyroid surgery is the primary treatment for substernal goiters, and iatrogenic injury to the recurrent laryngeal nerve (RNL) is always a risk. The literature suggests that iatrogenic lesions of the RNL post resection of substernal goiter are not equally distributed, being more frequent on the right recurrent laryngeal nerve (R-RLN) in comparison to the left recurrent laryngeal nerve (L-RLN). The relative paucity of basic anatomical and clinical reportages on R-RLN iatrogenic injuries and on the developmental factors that may help explain its higher incidence justifies this study's undertaking. Here we compare incidence of right versus left iatrogenic injuries to the RLN in surgical resections of substernal goiters and discuss the anatomical and embryological factors involved. This report is part of a larger retrospective observational cohort study of 239 patients surgically treated for substernal goiter in the Gaffrée and Guinle University Hospital, Rio de Janeiro, from 2006 to 2018. From 239 patients, 13 presented with iatrogenic RLN injury, one patient presented bilateral lesion, totalling 15 iatrogenic lesions. Our analysis showed that the R-RLN seems to be anatomically more vulnerable to injury due to the embryological underpinnings addressed in this review, R-RLN = 64.29% (n = 9) and L-RLN = 35.71% (n = 5). Pathological factors like malignancy and size of the mass are relevant issues to be considered. The knowledge of anatomical landmarks and embryological development of the thyroid and associated structures can improve our understanding and teaching of surgical anatomy, thus helping prevent and reduce the number of iatrogenic injuries on right RLNs.