Incidence of and Risk Factors for Perioperative Cardiovascular Complications in Spine Surgery

Background: An increasing number of patients are opting for spine surgery despite the associated risk of cardiovascular complications. The evidence regarding the incidence and risk factors of cardiovascular complications in spine surgery is insufficient. Therefore, we aimed to determine the incidence and risk factors for cardiovascular complications that occur perioperatively in spine surgery. Methods: This retrospective study included all patients who underwent spine surgery between January 2018 and December 2019 at a single center. Demographic, clinical, and operative data were collected from electronic medical records. The incidence of perioperative cardiac complications was determined. Univariate and multivariate analyses were performed to identify risk factors for the development of perioperative cardiovascular complications in the participants. Results: Of the 1,002 eligible patients enrolled in the study, six developed cardiac complications. Acute myocardial infarction, cardiac arrest, and congestive heart failure occurred in one, two, and three patients, respectively. Risk factors for cardiovascular complications included scoliosis surgery (relative risk: RR, 18.61; 95% confidence interval (CI): 1.346-257.35) and a history of congestive heart failure (RR, 120.97; 95% CI: 2.12-6898.80). Conclusion: The incidence of perioperative cardiovascular complications in patients who underwent spine surgery was 0.6%. High-risk patients should be closely monitored optimally managed throughout the perioperative period.

Comparison of Robot Versus Fluoroscopy-Assisted Pedicle Screw Instrumentation in Adolescent Idiopathic Scoliosis Surgery

The aim of this study is to explore whether robot-assisted technique has advantages over conventional fluoroscopy-assisted technique in clinical and radiological outcomes and whether it could decrease the incidence of mis-implantations of pedicle screws in AIS correction surgery.A total of 101 AIS patients were recruited (RA group: 45 patients underwent robot-assisted screw insertion; FA group: 56 patients underwent fluoroscopy-assisted screw insertion). When compared the radiological data between two groups, major and secondary curve were both corrected proficiently with no difference in the Cobb angle comparison at last follow-up, suggesting that both robot-assisted technique and fluoroscopy-assisted technique could lead to efficient radiographic correction and similar clinical outcomes (all, P<0.05). In RA group, operation time, blood loss and transfusion volume were significantly greater than those in FA group, while the accuracy of screw implantations in AIS patients with thoracic scoliotic curve in RA group was higher than that in FA group.In conclusion, both robot-assisted and fluoroscopy-assisted technique could reach proficient radiographic correction and similar clinical outcomes in AIS surgery. Compared with conventional fluoroscopy technique, robot-assisted technique might improve the accuracy of screw implantations in AIS patients with thoracic scoliotic curve, while the increased operation time, blood loss and transfusion volume might be the disadvantages due to preliminary stage of learning curve.

Efficacy and safety for combination of t-EMG with O-arm assisted pedicle screw placement in neurofibromatosis type I scoliosis surgery

Background Due to the characteristics of neurofibromatosis type I (NF-1) scoliosis, the precise placement of pedicle screws still remains to be a challenge. Triggered screw electromyography (t-EMG) has been proved to exhibit high sensitivity to identify mal-positioned pedicle screws, but no previous study assessed the combination of t-EMG with O-arm-assisted pedicle screw placement in NF-1 scoliosis surgery. Objective To evaluate efficacy and safety for combination of t-EMG with O-arm-assisted pedicle screw placement in NF-1 scoliosis surgery. Materials and methods From March 2018 to April 2020, sixty-five NF-1 scoliosis patients underwent t-EMG and O-arm-assisted pedicle screw fixation were retrospectively reviewed. The channel classification system was applied to classify the pedicle morphology based on pedicle width measurement by preoperative computed tomography scans. The minimal t-EMG threshold for screw path inspection was used as 8 mA, and operative screw redirection was also recorded. All pedicle screws were verified using a second intraoperative O-arm scan. The correlation between demographic and clinical data with amplitude of t-EMG were also analyzed. Results A total of 652 pedicle screws (T10-S1) in 65 patients were analyzed. The incidence of an absent pedicle (channel classification type C or D morphology) was 150 (23%). Overall, abnormal t-EMG threshold was identified in 26 patients with 48 screws (7.4%), while 16 out of the 48 screws were classified as G0, 14 out of the 48 screws were classified as G1, and 18 out of the 48 screws were classified as G2. The screw redirection rate was 2.8% (18/652). It showed that t-EMG stimulation detected 3 unacceptable mal-positioned screws in 2 patients (G2) which were missed by O-arm scan. No screw-related neurological or vascular complications were observed. Conclusions Combination of t-EMG with O-arm-assisted pedicle screw placement was demonstrated to be a safe and effective method in NF-1 scoliosis surgery. The t-EMG could contribute to detecting the rupture of the medial wall which might be missed by O-arm scan. Combination of t-EMG with O-arm could be recommended for routine use of screw insertion in NF-1 scoliosis surgery.

Robotic Sacroiliac Fixation Technique for Triangular Titanium Implant in Adult Degenerative Scoliosis Surgery: 2-Dimensional Operative Video

Corrective surgery remains a definitive treatment for adult spinal deformity, improving pain and disability. With these cases, instrumentation to the pelvis with iliac fixation is recommended. Whether iliac or S2-Alar-Iliac (S2AI) trajectories are used, sacroiliac joint pain and long-term sacroilitis can be common after long-fusion constructs.1-3 Sacroiliac fusion with triangular titanium implants during fusion can reduce back pain associated with sacroiliac joint degeneration,3 provides reduction in sacroiliac joint motion and stress when added to S2AI screws, and potentially enhances mechanical stability of fusion constructs.4 Here, we present a technique for placing triangular titanium sacroiliac implants (iFuse BedrockTM; SI-BONE Inc, Santa Clara, California) alongside S2AI screws using a robotic platform (Mazor X; Medtronic Sofamor Danek, Medtronic Inc, Dublin, Ireland). Navigated robotics allows reduction in human error with implant placement, and potentially decreased operative time/fluoroscopy.5-7 Key surgical steps include placement of K wires for S2AI and bilateral SI-implants, tapping, replacing SI-implant K wires with guide pins, placing S2AI screws, and finally placing the SI-implant. Final placement is verified with intraoperative fluoroscopy. The patient described is a 61-yr-old woman with worsening adult degenerative scoliosis, lower back pain, left leg radicular pain, and mild right leg pain who failed conservative treatment. Examination revealed diminished strength in both legs. Imaging was significant for moderate sigmoid scoliosis, discogenic disease, and osteoarthritis at all levels. She consented to undergo corrective surgery. Postoperatively, the patient experienced resolution of her leg weakness and pain. Imaging demonstrated appropriate positioning of hardware. Prospective studies on the efficacy of the SI-implant are underway.