World Neurosurg. 2019 Sep;129:e146-e151. doi: 10.1016/j.wneu.2019.05.064. Epub 2019 May 16.

Objective

The foundation of spine surgery centers on the proper identification, decompression, and stabilization of bony and neural elements. We describe easily reproducible and reliable methods for optimal decompression and release of neural structures to alleviate symptoms and improve patients' quality of life.

Methods

Multiple spinal decompression techniques were described in procedures for which the goal of surgery was decompression alone or decompression and fusion. Eight fundamental techniques were described: inverted U-cut, J-cut, T-cut, L-cut, Z-cut, I-track cuts, C-cut, and O-cut.

Results

These foundational cuts may be combined, as needed, to develop an individually tailored approach to the patient's pathology.

Conclusions

After properly identifying the anatomic structures, each of these techniques provides a consistent, reproducible, and efficient means to decompress the spine under various circumstances. These techniques provide surgical trainees with a framework for approaching surgical decompression.

World Neurosurg. 2019 Nov;131:e170-e175. doi: 10.1016/j.wneu.2019.07.102. Epub 2019 Jul 19.

Introduction

The lateral transpsoas approach (LTPA) has gained popularity in thoracolumbar spine surgery procedures; however, there is an insufficient amount of data pertaining to motor and sensory complications that arise when a corpectomy is performed through the LTPA approach.

Methods

Patients who underwent a corpectomy through a LTPA at a single institution between 2006 and 2016 were analyzed. Demographics, neurological outcomes, and complications were recorded. The minimum follow-up was 6 months. Univariate analysis was performed to compare demographics, surgical characteristics, complications, and outcome scores. To compare categorical variables, the χ2 test was used. For continuous outcomes, simple linear regression was used. Statistical significance was set at P < 0.05.

Results

A total of 166 patients were included. The patients were divided into 2 groups; LTPA without corpectomy (n = 112) versus LTPA with corpectomy (n = 54). Patients without corpectomy showed a significantly lower rate of postoperative infections compared with patients with corpectomy (3.6% vs. 22.2%; P < 0.000). A higher percentage of postoperative complications was found in patients with corpectomy (31.5% vs. 13.4%; P = 0.006). The rate of neurologic complications at the 6-month follow-up and the reoperation rate (22.7% vs. 32.4%; P = 0.256) were higher in the corpectomy group (8.9% vs. 7.4%; P = 0.741), no significant difference was found between the groups.

Conclusion

Patients who underwent an LTPA corpectomy have a higher risk to suffer from postoperative complications. The results at the 6-month follow-up did not significantly differ between the groups.

World Neurosurg. 2019 Sep 25. pii: S1878-8750(19)32520-3. doi: 10.1016/j.wneu.2019.09.090.

von Glinski A1, Yilmaz E2, Ishak B3, Ramey W4, Jack A4, Iwanaga J5, Abdul-Jabbar A3, Oskouian RJ3, Tubbs RS6, Chapman JR3.

Background

This study describes a modified iliac screw technique and compares it with the traditional iliac screw in regard to neurovascular structures at risk. Few studies have detailed the insertion point's surrounding anatomy and its relationship to vulnerable neurovascular structures when this modified technique is used. Therefore we describe our modified iliac screw entry and trajectory and detail the surrounding anatomy and neurovascular structures at risk with this technique in comparison with the “gold standard” trajectory.

Methods

The traditional iliac screw (TS) and modified iliac screw (MS) were placed into 12 fresh-frozen adult cadavers (3 female, 9 male). We measured the screw-to−supragluteal artery, vein, and nerve (SGANV) bundle and screw-to−sciatic notch distances. Further, we dissected the medial cortical border of the iliac screw to identify its final position with respect to the surrounding anatomy.

Results

No medial or lateral cortical breaches were visualized after screw placement. The MS was 18.31 mm from the greater sciatic foramen compared with 18.65 mm with the TS. The smallest distance from the MS to the greater sciatic foramen was 13.9 mm compared with 14.8 mm with the TS, an insignificant difference. The SGANV bundle−to-MS distance was 20.6 mm, and SGANV bundle−to-TS distance was 20.77 mm, again an insignificant difference.

Conclusions

Using the modified iliac screw technique does not change the intraosseous pathway (and thus bone purchase) with respect to the distance between the screw and neurovascular structures at risk.

World Neurosurg. 2019 Oct 16. pii: S1878-8750(19)32655-5. doi: 10.1016/j.wneu.2019.10.040.

von Glinski A1, Elia C2, Ansari D3, Yilmaz E4, Takayanagi A5, Norvell DC6, Pierre CA3, Abdul-Jabbar A3, Chapman JR7, Oskouian RJ3.

Background

Advancements in modern medicine have led to longer life expectancy. Literature on spinopelvic fixation in elderly patients is limited. We investigated morbidity and mortality in octogenarians who underwent spinopelvic fixation.

Methods

A retrospective chart review was conducted of patients who underwent spinopelvic fixation from January 2014 through December 2018 at a single institution. Patients were grouped into the octogenarian group (OG), 80–89 years old, and comparison group (CG), 40–50 years old. Demographics; pathology; Charlson Comorbidity Index; Hounsfield units; surgery details; and clinical data including complications, intensive care unit and length of hospital stay, and mortality were collected and compared.

Results

Inclusion criteria were met by 26 patients (OG: n = 14; CG: n = 12). Diagnoses in the OG were deformity (42.9%), pseudarthrosis (35.7%), fracture (7.1%), infection (7.1%), and tumor (7.1%). The only significant differences in baseline patient characteristics were that Charlson Comorbidity Index was significantly higher in the OG (6.0 ± 1.4) compared with the CG (1.1 ± 1.0) (P < 0.001) and the OG had lower Hounsfield units (P < 0.001), indicating poorer bone quality. More patients in the CG underwent staged and anterior approaches compared with the OG (P = 0.031). Major and minor complication rates were 57.1% and 42.9%, respectively, in the OG (P = 0.98) and 25% and 25% in the CG (P = 0.34). Mortality rate was 14.3%.

Conclusions

With an aging population, the number of patients requiring spinopelvic fixation will continue to grow. Spine surgeons must carefully weigh benefits and risks in patients with multiple comorbidities.

Global Spine J. 2019 Dec;9(8):881-894. doi: 10.1177/2192568219874771. Epub 2019 Nov 22.

Study Design:

Systematic review.

Objectives:

C5 palsy (C5P) is a not uncommon and disabling postoperative complication with a reported incidence varying between 0% and 30%. Among others, one explanation for its occurrence includes foraminal nerve root tethering. Although different risk factors have been reported, controversy about its causation and prevention persists. Inconsistent study findings contribute to the persistent ambiguity leading to an assumption of a multifactorial nature of the underlying C5P pathophysiology. Here, we report the results of a systematic review on C5P with narrow inclusion criteria in the hope of elucidating risk factors for C5P due to a common pathophysiological mechanism.

Methods:

Electronic databases from inception to March 9, 2019 and references of articles were searched. Narrow inclusion criteria were applied to identify studies investigating demographic, clinical, surgical, and radiographic factors associated with postoperative C5P.

Results:

Sixteen studies were included after initial screening of 122 studies. Eighty-four risk factors were analyzed; 27 in ≥2 studies and 57 in single studies. The pooled prevalence of C5P was 6.0% (range: 4.2%-24.1%) with no consistent evidence that C5P was associated with demographic, clinical, or specific surgical factors. Of the radiographic factors assessed, specifically decreased foraminal diameter and preoperative cord rotation were identified as risk factors for C5P.

Conclusion:

Although risk factors for C5P have been reported, ambiguity remains due to potentially multifactorial pathophysiology and study heterogeneity. We found foraminal diameter and cord rotation to be associated with postoperative C5P occurrence in our meta-analysis. These findings support the notion that factors contributing to, and acting synergistically with foraminal stenosis increase the risk of postoperative C5P.