Non-Neurologic Complications Following Surgery for Adolescent Idiopathic Scoliosis

Intrawound Vancomycin Powder Reduces Delayed Deep Surgical Site Infections Following Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective.

OBJECTIVE

Evaluate whether the use of vancomycin powder (VP) placed in the surgical site before wound closure prevents delayed deep surgical site infections (DDI).

SUMMARY OF BACKGROUND DATA

DDI after posterior spinal fusion (PSF) in adolescent idiopathic scoliosis (AIS) patients remains a significant and major complication. The use of VP to prevent acute surgical site infection has been reported, but the impact on DDI is unknown.

MATERIALS AND METHODS

AIS patients treated over the past 20 years with PSF or instrumentation from a large multicenter registry were reviewed. Patients were divided into two groups: intraoperative vancomycin powder placed in the wound (VP) or no antibiotics placed in the wound (NVP). DDI was defined as an infection that occurred >90 days after surgery and required surgical intervention in the operating room. Patients who developed a DDI had secondary verification of VP use or not. χ 2 and Kaplan-Meier (K-M) survivorship analyses were used to compare demographics and the incident rate of DDI between groups.

RESULTS

Totally, 4145 cases met the inclusion criteria for this study. A total of 43 DDI cases were identified (1.0%). The incidence of DDI for the VP group was 0.2% (4/2111), and 1.9% (39/2034) in the NVP group ( P <0.001). Given the difference in follow-up for the two groups, a cumulative survival and Kaplan-Meier analysis revealed the VP group had significantly better "survival" (no DDI) than the NVP group ( P <0.001).

CONCLUSION

DDIs are significant adverse events that can greatly complicate patient recovery after PSF for AIS, including rehospitalization. This study found that patients who received VP intraoperatively were 10 times less likely to develop a DDI than those who did not receive VP. Although other advances and changes in surgical techniques may contribute to the significant decrease in infections found in the more recent VP cohort, VP should be considered as a prophylactic measure.

LEVEL OF EVIDENCE

4.

A Novel Deformity Correction Manipulation System for Better Correction of Large Thoracic Scoliosis

OBJECTIVE

Treating patients with large thoracic scoliosis (between 70° and 100°) poses technical challenges, particularly with traditional correction techniques (TCT). To address this, we developed a novel deformity correction manipulation system (DCMS) aimed at reducing surgical complexity and trauma. This study aims to assess the safety and effectiveness of DCMS in treating large thoracic scoliosis.

METHODS

From January 2016 to June 2021, 76 patients with large thoracic scoliosis were included in this retrospective study. The patients were divided into two groups: DCMS (n = 34) and TCT (n = 42). Basic patient data including age at surgery, sex, etiology, Risser sign, flexibility of the main thoracic curve, instrumented levels, number of screws, duration of hospital stay, and follow-up time were collected and analyzed. Radiographic and clinical outcomes, as measured by various radiographic parameters and Scoliosis Research Society-30 (SRS-30) scores, were retrospectively analyzed and compared between the two groups. Adverse events were also documented. Statistical analyses were performed using two-tailed independent t-tests, chi-square tests, and Fisher's exact test.

RESULTS

The DCMS group exhibited significantly shorter operative times, reduced blood loss, and shorter hospital stays compared to the TCT group. However, there were no significant differences between the two groups in terms of age at surgery, sex, etiology, Risser sign, flexibility of the main curve, instrumented levels, number of screws, and follow-up time. While preoperative major curves were statistically similar between the two groups, the DCMS group achieved a superior correction rate compared to the TCT group (74.2% ± 8.8% vs 68.1% ± 10.5%). No significant differences were observed in other radiographic parameters, SRS-30 scores, or the incidence of adverse events.

CONCLUSION

The application of DCMS resulted in shorter operative times, reduced blood loss, shorter hospital stays, and greater curve correction compared to TCT. DCMS proves to be a safe and effective technique for treating large thoracic curves.

Pre-operative carbohydrate drink in pediatric spine fusion: randomized control trial

PURPOSE

As rapid discharge protocols for pediatric spine fusion shorten stays, gastrointestinal (GI) complications are uncovered and cause delays in discharge. A pre-operative carbohydrate (CHO) drink has been shown to improve perioperative GI symptoms and functional return but has not been examined in pediatric spine patients. We aimed to determine if a preoperative CHO drink is safe in pediatric spine fusion patients, and if it improves their comfort scores and return of bowel function.

METHODS

We prospectively randomized ASA-1 and -2 pediatric spine fusion patients to either a pre-anesthesia carbohydrate drink 2 h prior to surgery or to a control group (standard 8 h NPO), blinded to surgical team. We documented time to return to flatus, bowel movement, GI symptoms, and comfort scores for 72 h post-operatively or until discharge.

RESULTS

62 patients were randomized. There was no significant differences between the groups' pre-operative characteristics, surgical details, nor post-operative morphine dose equivalents, except for EBL (405 cc control, 340 cc CHO drink, p = 0.044). There were no perioperative complications related to ingestion of the CHO drink. CHO group had a positive trend for earlier return of flatus (21% vs. 3% return at 12 h), and comfort scores for anxiety and abdominal pain, but no statistically significant differences. There was no difference in length of stay or time to first bowel movement.

CONCLUSION

There were no complications related to ingestion of a CHO drink 2 h prior to pediatric spinal fusion surgery. Further studies are needed to develop a study blinded to the participants with larger sample size. Level of evidence I.

Preoperative Echocardiogram Does Not Contribute to Surgical Risk Assessment in Patients With Large Curve Scoliosis and No Cardiac Risk Factors

OBJECTIVE

Severe scoliosis can affect thoracic organs, potentially leading to cardiovascular abnormalities. Thus, echocardiograms have been suggested for use in preoperative screening in patients with significant scoliosis. However, the utility of preoperative heart screenings in patients without known or suspected heart problems is not well understood. This study aims to find the incidence of cardiac findings in patients with severe scoliosis ≥90° without cardiac history.

METHODS

A single-institution retrospective chart review was performed. Inclusion criteria were scoliosis patients with curves ≥90 degrees and a screening echocardiogram performed within 6 months of spine surgery. Patients with a previous cardiac history, diagnosis associated with cardiac comorbidities (eg, connective tissue disease), or major coronal curves <90 degrees were excluded. Echocardiogram reports and perioperative clinical notes from involved services (including orthopaedics, cardiology, and anesthesia) were reviewed. Any postoperative use of vasopressors and reasons for their use were recorded.

RESULTS

Overall, 50 patients met the inclusion criteria. The mean age at surgery was 14.0 ± 4.9 years old (range: 2 to 33). The mean major curve was 108 ± 19 degrees (range: 90 to 160 degrees). A normal echocardiogram was seen in 38 (76%), whereas 6 patients (12%) had mild dilation of the aortic sinus or root, 4 (8%) had mild valvular regurgitation, 1 patient had a small atrial septal defect, and 1 had a trace pericardial effusion. No patient had any changes made to their perioperative plan and one patient was advised to see a cardiologist postoperatively. Postoperatively, 8 patients (16%) received vasopressors to raise blood pressure to meet preset goal MAP, but only one of these 8 had a positive echocardiogram (mild valvular insufficiency), which was not seen as a contributing factor to the use of pressors.

CONCLUSIONS

This study suggests that screening echocardiograms for patients without a cardiac history or related symptoms does not contribute to the evaluation of perioperative risk or anesthetic management. Creating clear, evidence-based guidelines for the utilization of perioperative testing, like echocardiograms, can reduce the social, time, and financial burdens on families. Such guidelines are vital for appropriate risk assessment and proper utilization of health care resources.

LEVEL OF EVIDENCE

Level III.

A 10-year perspective on the question of whether surgeries for adolescent idiopathic scoliosis are "one and done"?

PURPOSE

Posterior scoliosis fusion (PSF) for adolescent idiopathic scoliosis (AIS) is considered a highly successful surgery with excellent outcomes. However, especially as many patients "graduate" from their pediatric surgeons, there is the need to quantify the long-term outcomes of such surgeries.

METHODS

The 2010-2022 Pearldiver M161 dataset was queried for those who were 10 to 18 years old with AIS undergoing PSF with at least 10 years follow-up. Patient characteristics were abstracted. Reoperations were identified based on coding for any subsequent thoracic/lumbar surgery/revision. The 10-year reoperation rate and reasons for reoperation were determined, and multivariate regression was performed to determine risk factors.

RESULTS

In total, 3,373 AIS PSF patients were identified. Of the study cohort, 324 (9.6%) underwent reoperation within 10-years with an interquartile range for timing of surgery of 81-658 days, of which 29.6% were done for infection. Reoperations were done within the first three months for 152 (46.9% of reoperations), three months to 2 years for 97 (29.9%), and 2 years to 10 years for 74 (22.8%). Based on multivariate regression, need for reoperation was associated with male sex (OR: 1.70), asthma (OR: 1.36) and greater than thirteen segments of instrumentation (OR: 1.48) (p < 0.05 for each) but not age, other comorbidities, or insurance.

CONCLUSIONS

The current study of a large national AIS PSF population found 9.6% to undergo reoperation in the 10 years following their index operation. Although specifics about the curve pattern could not be determined, the reoperation incidence and correlation with specific risk factors are notable and important for patient counselling.

Analysis of duration of different stages of surgery in posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) patients: comparison between severe versus non-severe AIS

PURPOSE

Prolonged surgical duration in severe adolescent idiopathic scoliosis (AIS) patients is associated with increased blood loss and perioperative complications. The aim of this study was to compare the duration of each stage of posterior spinal fusion (PSF) in severe AIS (Cobb angle ≥ 90°) with non-severe AIS patients. This analysis will identify the most time-consuming stage of PSF and help surgeons formulate strategies to shorten operative time.

METHODS

Retrospective study whereby 90 AIS patients (Lenke type 2, 3, 4, and 6) who underwent PSF from 2019 to 2023 were recruited. Twenty-five severe AIS patients were categorized in Gp1 and 65 non-severe AIS patients in Gp2. Propensity score matching (PSM) with one-to-one with nearest neighbor matching (match tolerance 0.05) was performed. Outcomes measured via operation duration of each stage of surgery, blood loss, number of screws, fusion levels and screw density.

RESULTS

Twenty-five patients from each group were matched. Total operative time was significantly higher in Gp1 (168.2 ± 30.8 vs. 133.3 ± 24.0 min, p < 0.001). The lengthiest stage was screw insertion which took 58.5 ± 13.4 min in Gp1 and 44.7 ± 13.7 min in Gp2 (p = 0.001). Screw insertion contributed 39.5% of the overall increased surgical duration in Gp1. Intraoperative blood loss (1022.2 ± 412.5 vs. 714.2 ± 206.7 mL, p = 0.002), number of screws (17.1 ± 1.5 vs. 15.5 ± 1.1, p < 0.001) and fusion level (13.1 ± 0.9 vs. 12.5 ± 1.0, p = 0.026) were significantly higher in Gp1.

CONCLUSION

Screw insertion was the most time-consuming stage of PSF and was significantly longer in severe AIS. Adjunct technologies such as CT-guided navigation and robotic-assisted navigation should be considered to reduce screw insertion time in severe AIS.

Single Long-Incision Minimally Invasive Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study is to determine differences in outcomes in patients with adolescent idiopathic scoliosis undergoing spinal deformity correction surgery using a posterior spinal fusion (PSF) approach versus single and triple-incision minimally invasive surgery (MIS).

SUMMARY OF BACKGROUND DATA

MIS increased in popularity as surgeons' focus moved towards soft tissue preservation, but it carries technical demands and increased surgical time compared with PSF.

PATIENTS AND METHODS

Surgeries performed from 2016 to 2020 were included. Cohorts were formed based on surgical approach: PSF versus single long-incision MIS (SLIM) versus traditional MIS [3-incision MIS (3MIS)]. There were a total of 7 subanalyses. Demographic, radiographic, and perioperative data were collected for the 3 groups. Kruskal-Wallis and χ 2 tests were used for continuous and categorical variables, respectively.

RESULTS

Five hundred thirty-two patients met our inclusion criteria, 294 PSF, 179 3MIS, and 59 SLIM.Estimated blood loss (mL) ( P < 0.00001) and length of stay (LOS) ( P < 0.00001) was significantly higher in PSF than in SLIM and 3MIS. Surgical time was significantly higher in 3MIS than in PSF and SLIM ( P = 0.0012).Patients who underwent PSF had significantly lower postoperative T5 to T12 kyphosis ( P < 0.00001) and percentage kyphosis change ( P < 0.00001). Morphine equivalence was significantly higher in the PSF group during total hospital stay ( P = 0.0042).Patients who underwent SLIM and 3MIS were more likely to return to noncontact ( P = 0.0096) and contact sports ( P = 0.0095) within 6 months and reported lower pain scores ( P < 0.001) at 6 months postoperation.

CONCLUSION

SLIM has a similar operative time to PSF and is technically similar to PSF while maintaining the surgical and postoperative outcome advantages of 3MIS.

Navigation-Assisted One-Staged Posterior Spinal Fusion Using Pedicle Screw Instrumentation in Adolescent Idiopathic Scoliosis-A Case Series

Background and Objectives: Adolescent idiopathic scoliosis (AIS) is a prevalent three-dimensional spinal disorder, with a multifactorial pathogenesis, including genetics and environmental aspects. Treatment options include non-surgical and surgical treatment. Surgical interventions demonstrate positive outcomes in terms of deformity correction, pain relief, and improvements of the cardiac and pulmonary function. Surgical complications, including excessive blood loss and neurologic deficits, are reported in 2.27-12% of cases. Navigation-assisted techniques, such as the O-arm system, have been a recent focus with enhanced precision. This study aims to evaluate the results and complications of one-stage posterior instrumentation fusion in AIS patients assisted by O-arm navigation. Materials and Methods: This retrospective study assesses 55 patients with AIS (12-28 years) who underwent one-stage posterior instrumentation correction supported by O-arm navigation from June 2016 to August 2023. We examined radiological surgical outcomes (initial correction rate, loss of correction rate, last follow-up correction rate) and complications as major outcomes. The characteristics of the patients, intraoperative blood loss, operation time, number of fusion levels, and screw density were documented. Results: Of 73 patients, 55 met the inclusion criteria. The average age was 16.67 years, with a predominance of females (78.2%). The surgical outcomes demonstrated substantial initial correction (58.88%) and sustained positive radiological impact at the last follow-up (56.56%). Perioperative complications, including major and minor, occurred in 18.18% of the cases. Two patients experienced a major complication. Blood loss (509.46 mL) and operation time (402.13 min) were comparable to the literature ranges. Trend analysis indicated improvements in operation time and blood loss over the study period. Conclusions: O-arm navigation-assisted one-stage posterior instrumentation proves reliable for AIS corrective surgery, achieving significant and sustained positive radiological outcomes, lower correction loss, reduced intraoperative blood loss, and absence of implant-related complications. Despite the challenges, our study demonstrates the efficacy and maturation of this surgical approach.

Postoperative complications following Schwab-grade-I versus Schwab-grade-II PCO in treating severe rigid kyphoscoliosis patients: comparative matched-group outcomes with minimum 2-year follow-up

BACKGROUND CONTEXT

Standard partial facetectomies, (Smith-Petersen Osteotomy, (SPO), (Schwab-grade-I) and complete facet resection also known as Ponte osteotomy, (PO), (Schwab-grade-II) are narrowly akin and collectively appreciated as posterior column shortening osteotomies (PCOs). The former is considered a gentler osteotomy grade than the latter. The spine literature provides very little information on their comparison regarding perioperative complications and major curve correction rate outcomes.

PURPOSE

To determine whether Schwab-grade-I PCO (SPO) and Schwab-grade-II PCO (PO) are comparably safe in the surgical management of severe rigid scoliosis or kyphoscoliosis patients.

STUDY DESIGN/SETTING

Retrospective single-center comparative clinical study.

PATIENT SAMPLE

A total of 38 patients with severe rigid scoliosis or kyphoscoliosis were propensity score matched in this study, (SPO-treated); n=21 (55.30%) and (PO-treated); n=17 (44.70%), who underwent primary spinal deformity corrective surgery, respectively.

OUTCOME MEASURES

Outcomes included demographics, baseline pulmonary functional outcomes, perioperative complications incidence, hospital costs, Oswestry disability index (ODI), and the Scoliosis Research Society-22 (SRS-22) questionnaire scores.

METHODS

Following approval by the Institutional Review Board (IRB) of Beijing Chaoyang Hospital-Affiliated Capital Medical University in Beijing, out of a total of 82 consecutive surgical patients with complete data demonstrating severe and/or rigid spinal deformity, a pool of 38 of the 82 (46.3%) propensity-matched adult (≥18 years) patients with severe rigid scoliosis or kyphoscoliosis defined with a preoperative major curve magnitude of ≥80° on anteroposterior plain radiographs, and flexibility of <25% on bending plain radiographs who underwent primary spinal deformity corrective surgery were retrospectively evaluated. The patients were dichotomized into two osteotomy groups: standard (partial) facetectomy (SPO-treated), n=21 with an average age of 24.67 years, (Schwab-grade-I PCO) and complete facet excision, (PO-treated), (ie, Schwab-grade-II PCO), n=17 with an average age of 23.12 years. The minimum follow-up period was 2 years. Primary outcomes included baseline demographics and clinical features. Secondary outcomes included perioperative [intraoperative, immediate, and 2-year postoperative] complication rates. Tertiary outcomes included perioperative ODI and SRS-22 scores. Statistical analyses were carried out by Student t-test and Pearson's Chi-square test (Fisher's Exact Test), through Python statistical software package. Statistical significance was set at (p<.05).

RESULTS

Of the 38 matched severe rigid scoliosis or kyphoscoliosis patients, 55.30% (n=21) were SPO-treated and 44.70% (n=17) were PO-treated patients, respectively. The overall average age of patients was 23.97 years, with a female incidence of 76.32%. Major curve correction rates were 49.19% and 57.40% in SPO-treated and PO-treated patients, respectively, (p>.05). Immediately following surgery, comparable overall complication rates of 28.57% (n=6/21) versus 29.41% (n=5/17) were observed in the SPO-treated and PO-treated patients, respectively, (p=.726). We observed incidences of 9.52%, (n=2/21) versus 5.88%, (n=1/17) for surgical intensive care unit (SICU) admission, and incidences of 4.76%, (n=1/21) versus 5.88%, (n=1/17) for cardiopulmonary events in SPO-treated versus PO-treated patients following corrective surgery, respectively, (p>.05). The incidences of neurological deficits in the SPO-treated and PO-treated patients were respectively, 14.29%, (n=3/21) versus 17.65%, (n=3/17) immediately following surgery, (p>.05), and 0.00%, (n=0/21) in SPO-treated versus 14.28%, (n=3/21) in PO-treated patients at ≥2 years postoperative, (p<.05). Among the three patients that reported neurological deficits in the PO-treated group at ≥2 years postoperative, two patients had pre-existing baseline neurological deficits. The ODI score in the PO-treated group was significantly inferior at a minimum 2-year follow-up, (p<.05).

CONCLUSIONS

In the current study, both SPO-treated and PO-treated patients demonstrated statistically comparable surgical complications immediately following corrective surgery. Severe rigid kyphoscoliosis patients with preexisting baseline neurological deficits were more inclined to sustain neurological morbidity following corrective surgery. PCO corrective techniques are warranted as safe options for treating patients with severe rigid spine deformity phenotypes.

Do Children With Medicaid Insurance Have Increased Revision Rates 5 Years After Posterior Spinal Fusions?

BACKGROUND

Socioeconomic disparities in musculoskeletal care are increasingly recognized, however, no studies to date have investigated the role of the insurance carrier on outcomes after posterior spinal fusion (PSF) with segmental spinal instrumentation for adolescent idiopathic scoliosis (AIS).

METHODS

A US insurance dataset was queried using the PearlDiver Mariner software for all patients aged 10 to 18 undergoing PSF for a primary diagnosis of AIS between 2010 and 2020. Age, sex, geographic region, number of levels fused, and baseline medical comorbidities were queried. Complications occurring within 90 days of the index surgery were queried using the International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, 10th Revision (ICD-10) codes. Revision surgery was also queried up to 5 years after the index PSF. Categorical variables were compared using the Fisher χ 2 tests and continuous variables were compared using independent t tests. All-cause revision within 5 years was compared using the Kaplan-Meier analysis and a log-rank test. Significance was set at P -value <0.05.

RESULTS

A total of 10,794 patients were identified with 9006 (83.4%) patients with private insurance and 1788 (16.6%) patients insured by Medicaid. The mean follow-up in the database was 5.36±3 years for patients with private insurance and 4.78±2.9 years for patients with Medicaid insurance ( P <0.001). Children with AIS and Medicaid insurance had a significantly higher prevalence of asthma, hypertension, and obesity. A larger percentage of children with Medicaid insurance (41.3%) underwent a ≥13-level PSF compared with privately insured children (34.5%) ( P <0.001). Medicaid patients did not experience higher odds of postoperative complications; in addition, revision surgeries occurred in 1.1% and 1.8% of patients with private insurance and Medicaid insurance, respectively at 5 years postoperatively ( P =0.223).

CONCLUSION

Despite worse baseline comorbidities and longer fusion constructs, AIS patients insured with Medicaid did not have higher rates of complications or revisions at 5-year follow-up versus privately insured patients.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Does a dedicated "Scoliosis Team" and surgical standardization improve outcomes in adolescent idiopathic scoliosis surgery and is it reproducible?

PURPOSE

The objective of this study was to determine if standardization improves adolescent idiopathic scoliosis (AIS) surgery outcomes and whether it is transferrable between institutions.

METHODS

A retrospective review was conducted of AIS patients operated between 2009 and 2021 at two institutions (IA and IB). Each institution consisted of a non-standardized (NST) and standardized group (ST). In 2015, surgeons changed institutions (IA- > IB). Reproducibility was determined between institutions. Median and interquartile ranges (IQR), Kruskal-Wallis, and χ2 tests were used.

RESULTS

500 consecutive AIS patients were included. Age (p = 0.06), body mass index (p = 0.74), preoperative Cobb angle (p = 0.53), and levels fused (p = 0.94) were similar between institutions. IA-ST and IB-ST had lower blood loss (p < 0.001) and shorter surgical time (p < 0.001). IB-ST had significantly shorter hospital stay (p < 0.001) and transfusion rate (p = 0.007) than IB-NST. Standardized protocols in IB-ST reduced costs by 18.7%, significantly lowering hospital costs from $74,794.05 in IB-NST to $60,778.60 for IB-ST (p < 0.001). Annual analysis of surgical time revealed while implementation of standardized protocols decreased operative time within IA, when surgeons transitioned to IB, and upon standardization, IB operative time values decreased once again, and continued to decrease annually. Additions to standardized protocol in IB temporarily affected the operative time, before stabilizing.

CONCLUSION

Surgeon-led standardized AIS approach and streamlined surgical steps improve outcomes and efficiency, is transferrable between institutions, and adjusts to additional protocol changes.

Radiographic and perioperative outcomes following anterior thoracic vertebral body tethering and posterior lumbar spine tethering: a pilot series

BACKGROUND AND CONTEXT

 In patients with adolescent idiopathic scoliosis (AIS) of main thoracic and lumbar spine regions, combined anterior thoracic vertebral body tethering and posterior lumbar spine tethering (ATVBT/PLST) is a novel non-fusion treatment option for growth modulation and conservation of motion.

METHODS

 Fourteen patients with AIS who underwent ATVBT/PLST with at least 2-year follow-up were included. Primary outcomes included quality of life as assessed by SRS-22 instruments, radiographic analysis, and revision operations. We secondarily reported perioperative metrics and post-operative opiate morphine equivalents (OME). Clinical success was defined as patients who achieved skeletal maturity with ≤ 30° curve magnitude of both their main thoracic and thoracolumbar/lumbar curves and who did not undergo posterior spine instrumentation and fusion (PSIF).

RESULTS

Patients had a mean age of 11.6 years (range 10-14 years), majority were girls (92%), and mean follow-up was 3.0 years (range 2-4.8 years). All patients were skeletally immature with a Risser ≤ 2. Included curves were Lenke 1C, 3C, or 6C. Mean preoperative curve magnitudes were 53° ± 8° (range 45°-65°) main thoracic and 49° ± 9° (range 40°-62°) thoracolumbar/lumbar curves. At most recent follow-up, patients had a mean main thoracic curve of 29° ± 8° (range 15°-40°) and a mean thoracolumbar/lumbar curve of 20° ± 15° (range 4°-35°). 50% required a revision operation. Cable breakage occurred in 43%, which did not always require revision. One patient progressed to thoracic fusion, but no patient underwent lumbar fusion. Patients had a mean SRS-22 outcome score of 4.2 ± 0.4.

CONCLUSIONS

ATVBT/PLST is a potential alternative to spine fusion for select immature patients with AIS at a minimum 2-year follow-up. ATVBT/PLST potentially offers motion conservation at the cost of a higher revision rate. Further study and reporting of results are necessary to refine indications and techniques, which in turn will improve outcomes of this procedure.

LEVEL OF EVIDENCE

Level IV-Case series without comparative group.

Perioperative Complications and Health-related Quality of Life Outcomes in Severe Pediatric Spinal Deformity

STUDY DESIGN

Prospective multicenter cohort study.

OBJECTIVE

To evaluate perioperative complications and mid-term outcomes for severe pediatric spinal deformity.

SUMMARY OF BACKGROUND DATA

Few studies have evaluated the impact of complications on health-related quality of life (HRQoL) outcomes in severe pediatric spinal deformity.

METHODS

Patients from a prospective, multicenter database with severe pediatric spinal deformity (minimum of 100 degree curve in any plane or planned vertebral column resection (VCR)) with a minimum of 2-years follow-up were evaluated (n=231). SRS-22r scores were collected preoperatively and at 2-years postoperatively. Complications were categorized as intraoperative, early postoperative (within 90-days of surgery), major, or minor. Perioperative complication rate was evaluated between patients with and without VCR. Additionally, SRS-22r scores were compared between patients with and without complications.

RESULTS

Perioperative complications occurred in 135 (58%) patients, and major complications occurred in 53 (23%) patients. Patients that underwent VCR had a higher incidence of early postoperative complications than patients without VCR (28.9% vs. 16.2%, P =0.02). Complications resolved in 126/135 (93.3%) patients with a mean time to resolution of 91.63 days. Unresolved major complications included motor deficit (n=4), spinal cord deficit (n=1), nerve root deficit (n=1), compartment syndrome (n=1), and motor weakness due to recurrent intradural tumor (n=1). Patients with complications, major complications, or multiple complications had equivalent postoperative SRS-22r scores. Patients with motor deficits had lower postoperative satisfaction subscore (4.32 vs. 4.51, P =0.03), but patients with resolved motor deficits had equivalent postoperative scores in all domains. Patients with unresolved complications had lower postoperative satisfaction subscore (3.94 vs. 4.47, P =0.03) and less postoperative improvement in self-image subscore (0.64 vs. 1.42, P =0.03) as compared to patients with resolved complications.

CONCLUSION

Most perioperative complications for severe pediatric spinal deformity resolve within 2-years postoperatively and do not result in adverse HRQoL outcomes. However, patients with unresolved complications have decreased HRQoL outcomes.

Benefits of Best Practice Guidelines in Spine Fusion: Comparable Correction in AIS with Higher Density and Fewer Complications

BACKGROUND

There is significant variability in surgeons' instrumentation patterns for adolescent idiopathic scoliosis surgery. Implant density and costs are difficult to correlate with deformity correction, safety, and quality of life measures.

MATERIALS AND METHODS

Two groups of postoperative adolescents were compared based on exposure to a best practice guidelines program (BPGP) introduced to decrease complications. Hybrid and stainless steel constructs were dropped, and posterior-based osteotomies, screws, and implant density were increased to 66.8 ± 12.03 vs. 57.5 ± 16.7% (p < 0.001). The evaluated outcomes were: initial and final correction, rate of correction loss, complications, OR returns, and SRS-22 scores (minimum two-year follow-up).

RESULTS

34 patients were operated on before BPGP and 48 after. The samples were comparable, with the exceptions of a higher density and longer operative times after BPGP. Initial and final corrections before BPGP were 67.9° ± 22.9 and 64.6° ± 23.7; after BPGP, the corrections were 70.6° ± 17.4 and 66.5° ± 14.9 (sd). A regression analysis did not show a relation between the number of implants and postoperative correction (beta = -0.116, p = 0.307), final correction (beta = -0.065, p = 0.578), or loss of correction (beta= -0.137, p = 0.246). Considering screw constructs only (n = 63), a regression model controlled for flexibility continued to show a slight negative effect of density on initial correction (b = -0.274; p = 0.019). Only with major curve concavity was density relevant in initial correction (b = 0.293; p = 0.038), with significance at 95% not being achieved for final correction despite a similar beta (b = 0.263; p = 0.069). Complications and OR returns dropped from 25.6% to 4.2%. Despite this, no difference was found in SRS-22 (4.30 ± 0.432 vs. 4.42 ± 0.39; sd) or subdomain scores pre- and post-program.

FINDINGS

Although it appears counterintuitive that higher density, osteotomies, and operative time may lead to fewer complications, the study shows the value of best practice guidelines in spinal fusions. It also shows that a 66% implant density leads to better safety and efficacy, avoiding higher costs.

Novel Machine Vision Image Guidance System Significantly Reduces Procedural Time and Radiation Exposure Compared With 2-dimensional Fluoroscopy-based Guidance in Pediatric Deformity Surgery

BACKGROUND

Intraoperative 2-dimensional (2D) fluoroscopy imaging has been commonly adopted for guidance during complex pediatric spinal deformity correction. Despite the benefits, fluoroscopy imaging emits harmful ionizing radiation, which has been well-established to have deleterious effects on the surgeon and operating room staff. This study investigated the difference in intraoperative fluoroscopy time and radiation exposure during pediatric spine surgery between 2D fluoroscopy-based navigation and a novel machine vision navigation system [machine vision image guidance system (MvIGS)].

METHODS

This retrospective chart review was conducted at a pediatric hospital with patients who underwent posterior spinal fusion for spinal deformity correction from 2018 to 2021. Patient allocation to the navigation modality was determined by the date of their surgery and the date of implementation of the MvIGS. Both modalities were the standard of care. Intraoperative radiation exposure was collected from the fluoroscopy system reports.

RESULTS

A total of 1442 pedicle screws were placed in 77 children: 714 using MvIGS and 728 using 2D fluoroscopy. There were no significant differences in the male-to-female ratio, age range, body mass index, distribution of spinal pathologies, number of levels operated on, types of levels operated on, and the number of pedicle screws implanted. Total intraoperative fluoroscopy time was significantly reduced in cases utilizing MvIGS (18.6 ± 6.3 s) compared with 2D fluoroscopy (58.5 ± 19.0 s) ( P < 0.001). This represents a relative reduction of 68%. Intraoperative radiation dose area product and cumulative air kerma were reduced by 66% (0.69 ± 0.62 vs 2.0 ± 2.1 Gycm 2 , P < 0.001) and 66% (3.4 ± 3.2 vs 9.9 ± 10.5 mGy, P < 0.001) respectively. The length of stay displayed a decreasing trend with MVIGS, and the operative time was significantly reduced in MvIGS compared with 2D fluoroscopy for an average of 63.6 minutes (294.5 ± 15.5 vs 358.1 ± 60.6 min, P < 0.001).

CONCLUSION

In pediatric spinal deformity correction surgery, MvIGS was able to significantly reduce intraoperative fluoroscopy time, intraoperative radiation exposure, and total surgical time, compared with traditional fluoroscopy methods. MvIGS reduced the operative time by 63.6 minutes and reduced intraoperative radiation exposure by 66%, which may play an important role in reducing the risks to the surgeon and operating room staff associated with radiation in spinal surgery procedures.

LEVEL OF EVIDENCE

Level III; retrospective comparative study.

Surgical Site Infection After Primary Spinal Fusion Surgery for Adolescent Idiopathic Scoliosis: An Analysis of Risk Factors From a Nationwide Insurance Database

STUDY DESIGN

Retrospective review.

OBJECTIVE

The purpose of this study was to quantify the incidence and factors associated with surgical site infection (SSI) in pediatric patients undergoing spinal fusion for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Infection is a morbid complication after spinal fusion. The incidence of SSI after pediatric spinal fusion is likely underestimated; the use of a national database allows for a comprehensive assessment of this rare outcome.

MATERIALS AND METHODS

The PearlDiver Database was used to identify AIS patients who underwent primary instrumented spinal fusion between 2010 and 2019 and relevant patient records were queried to identify infections within 7, 30, and 90 postoperative days. Patients with nonidiopathic scoliosis were excluded. Logistic regression was used to evaluate risk factors associated with postoperative infection.

RESULTS

Out of 9801 patients who underwent primary fusion for AIS, 44 patients (0.4%) developed an infection within 7 postoperative days. The 30 days and 90 days incidences were 1.9% and 2.7%, respectively. Within 90 days, 154 (57.7%) of the patients with infection had undergone reoperation, of whom 72 underwent multiple reoperations. Obesity and male sex ( P < 0.05) were significantly associated with postoperative infection. The length of fusion was not a significant factor in the development of SSI ( P > 0.05). Eleven patients underwent an operation requiring hardware removal within 90 days. There were no significant factors associated with those undergoing hardware removal compared with those undergoing surgical debridement.

CONCLUSIONS

The study identified a 2.7% 90 days incidence of SSI after posterior spinal fusion for AIS, with 57.7% of all infections requiring a return to the operating room. Preoperative patient-related characteristics associated with increased risk of postoperative SSI were male sex and obesity. The current study can be used to provide preoperative counseling regarding the risk of this postoperative complication.

LEVEL OF EVIDENCE

Level III.

Intraoperative Blood Loss at Different Surgical-Procedure Stages during Posterior Spinal Fusion for Idiopathic Scoliosis

Background and Objectives: Several predictive factors have been reportedly associated with intraoperative total blood loss (TBL) during posterior spinal fusion (PSF) for idiopathic scoliosis (IS). To reduce TBL, preoperative factors and interoperative factors are considered important. However, there are few reports that have evaluated bleeding patterns according to surgical stages. This study aimed to elucidate bleeding patterns at different surgical stages and determine the predictive factors for TBL during PSF surgery in patients with IS. Materials and Methods: Preoperative data, radiographic parameters, and intraoperative data of patients undergoing PSF for IS were retrospectively collected. We divided the patients into six stages: stage 1, exposure; stage 2, implant placement; stage 3, release; stage 4, correction; stage 5, bone grafting; and stage 6, closure; then we reviewed the blood loss and bleeding speed. Multiple-regression analysis was performed to generate a predictive formula for blood loss using preoperative and intraoperative factors, including blood loss at stage 1, as explanatory variables. Results: Forty-five patients (mean age: 17.6 years) were included. The mean operative time and TBL were 287.9 min and 756.5 mL, respectively. Blood loss was the highest at stage 3, followed by stage 4. Bleeding speed was the highest at stage 4, followed by stage 3. Bleeding speeds at stages 3 and 4 were significantly higher than those at stages 1 and 2. Preoperative Cobb angle, activated partial thromboplastin time (aPTT), number of fused vertebrae, and blood loss at stage 1 were significant contributing factors. Conclusions: Blood loss and bleeding speed during the release and correction stages were high. Specifically, bleeding speed significantly increased during and after the release procedure. The preoperative Cobb angle, aPTT, number of fixed vertebrae, and blood-loss volume during PSF were significantly associated with TBL. Our findings would be helpful for reducing TBL in patients undergoing PSF for IS.

The Impact of Prematurity at Birth on Short-Term Postoperative Outcomes Following Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis

Prematurity is associated with surgical complications. This study sought to determine the risk of prematurity on 30-day complications, reoperations, and readmissions following ≥7-level PSF for AIS which has not been established. Utilizing the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP)-Pediatric dataset, all AIS patients undergoing ≥7-level PSF from 2012-2016 were identified. Cases were 1:1 propensity score-matched to controls by age, sex, and number of spinal levels fused. Prematurity sub-classifications were also evaluated: extremely (<28 weeks), very (28-31 weeks), and moderate-to-late (32-36 weeks) premature. Univariate analysis with post hoc Bonferroni compared demographics, hospital parameters, and 30-day outcomes. Multivariate logistic regression identified independent predictors of adverse 30-day outcomes. 5531 patients (term = 5099; moderate-to-late premature = 250; very premature = 101; extremely premature = 81) were included. Premature patients had higher baseline rates of multiple individual comorbidities, longer mean length of stay, and higher 30-day readmissions and infections than the term cohort. Thirty-day readmissions increased with increasing prematurity. Very premature birth predicted UTIs, superficial SSI/wound dehiscence, and any infection, and moderate-to-late premature birth predicted renal insufficiency, deep space infections, and any infection. Prematurity of AIS patients differentially impacted rates of 30-day adverse outcomes following ≥7-level PSF. These results can guide preoperative optimization and postoperative expectations.

Venous Thromboembolic Events are Exceedingly Rare in Spinal Fusion for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Review of health care record database and determination of population statistics.

OBJECTIVE

The purpose of this study was to quantify the incidence of clinically significant venous thromboembolic (VTE) events in patients undergoing spinal fusion surgery for adolescent idiopathic scoliosis (AIS) and to identify risk factors for VTE.

SUMMARY OF BACKGROUND DATA

VTE is a serious complication that can cause disability and even death following surgery. Incidence of VTE following AIS surgery has not been well studied; the use of a national database allows the assessment of rare, yet important complications.

MATERIALS AND METHODS

The PearlDiver Database was used to identify AIS patients who underwent primary instrumented spinal fusion between 2010 and 2020. Patient records were cross-referenced for documented VTEs within 30 and 90 postoperative days. Patients with nonidiopathic scoliosis were excluded. Logistic regression was used to evaluate risk factors for correlation with VTE events.

RESULTS

Thirty-eight of 11,775 (0.323%) patients undergoing surgery for AIS developed a VTE complication within 90 postoperative days. Hypercoagulability [odds ratio (OR)=13.50, P <0.0001], spinal fusion involving 13+ vertebral levels (OR=2.61, P <0.0001), obesity (OR=1.30, P <0.005), and older (15-18 y) compared with younger adolescence (10-14 y) (OR=2.12, P <0.0001) were associated with VTE. Seven of 38 (18.4%) patients with a diagnosed thrombophilia experienced VTE.

CONCLUSIONS

The incidence of clinically significant VTEs in pediatric patients following spinal fusion surgery for AIS is low with an incidence of 0.323%. Postoperative chemoprophylaxis in the general pediatric population is not indicated. Patients with obesity, those undergoing spinal fusion of 13 or more vertebrae, and adolescents 15-18 years old were found to have higher but still small risk of VTE following surgery. Further prospective studies are needed to validate the risk profile of patients with hypercoagulability and establish clinical guidelines for use of postoperative chemoprophylaxis in this cohort.

LEVEL OF EVIDENCE

Level III.

Incidence of radiographic pulmonary abnormalities after posterior spinal fusion surgery for pediatric scoliosis

Background and Aims

Pulmonary complications are the most common non-neurologic complications following surgical correction of scoliosis. These can affect postoperative recovery by increasing the length of stay and/or the need for ventilatory support. The aim of this retrospective study is to determine the incidence of radiographic abnormalities reported in chest radiography after posterior spinal fusion surgery for the treatment of scoliosis in children.

Material and Methods

A retrospective chart review of all patients who underwent posterior spinal fusion surgery in our center between January 2016 and December 2019 was attempted. Radiographic data including chest and spine radiographs were reviewed on the national integrated medical imaging system using medical record numbers for all patients in the 7 postoperative days.

Results

Seventy-six (45.5%) of the 167 patients developed radiographic abnormalities in the postoperative period. There was evidence of atelectasis in 50 (29.9%) patients, pleural effusion in 50 (29.9%) patients, pulmonary consolidation in 8 (4.8%) patients, pneumothorax in 6 (3.6%) patients, subcutaneous emphysema in 5 (3%) patients, and rib fracture in 1 (0.6%) patient. Four (2.4%) patients were noted to have an intercostal tube inserted postoperatively, three for treating pneumothorax, and one for pleural effusion.

Conclusion

A large number of radiographic pulmonary abnormalities were encountered in children following surgical treatment of pediatric scoliosis. Although not all radiographic findings may be clinically significant, early recognition may guide clinical management. The incidence of air leak (pneumothorax, subcutaneous emphysema) was significant and could influence local protocol formulation with regards to obtaining immediate postoperative chest radiograph and intervention if clinically necessary.

A Comparison Between the Perioperative Outcomes of Female Adolescent Idiopathic Scoliosis (AIS) Versus Adult Idiopathic Scoliosis (AdIS) Following Posterior Spinal Fusion: A Propensity Score Matching Analysis Involving 425 Patients

STUDY DESIGN

Retrospective propensity score matching (PSM) study.

OBJECTIVE

To investigate the perioperative outcomes comparing adolescent idiopathic scoliosis (AIS) and adult idiopathic scoliosis (AdIS) patients following posterior spinal fusion (PSF).

METHODS

425 female AIS and AdIS patients who were operated (between January 2015 to March 2020) using a dual attending surgeon strategy were stratified into G1 (AIS aged 10-16 years old) and G2 (AdIS > 20 years old). PSM analysis with one-to-one, nearest neighbor matching technique with match tolerance of 0.001 was used to matched 357 AIS patients to 68 AdIS patients. Operation duration, intraoperative blood loss (IBL), blood loss percentage, hemoglobin drift, blood salvaged, postoperative wound length, allogenic blood transfusion requirement, postoperative hospital stay, postoperative Cobb, correction rate and postoperative complications were documented and reported.

RESULTS

Following PSM, G1 and G2 each had 50 patients with comparable and balanced covariates. As anticipated, G2 patients were heavier, taller and had higher body mass index compared to G1 patients (P < 0.05). We could not find any significant differences in the perioperative outcome comparing this 2 groups. AIS and AdIS patients had similar operation duration (125.9 ± 27.2 min vs 127.3 ± 37.8 min), IBL (749.8 ± 315.7 ml vs 723.8 ± 342.1 ml) and length of hospital stay (3.3 ± 0.4 days vs 3.5 ± 0.8 days) (P > 0.05). Hemoglobin drift and amount of blood salvaged were comparable (P > 0.05). G2 had stiffer curves. There was a trend toward a lower correction rate in G2 in the immediate postoperative period, however it did not reach statistical significance (61.8 ± 11.2% vs. 66.3 ± 11.6%, P = 0.051). No patients required blood transfusion and none had any postoperative complications.

CONCLUSION

Adolescent and adult female scoliosis patients had comparable perioperative outcome following PSF surgery that was carried out using a dual attending surgeon strategy.

Perioperative prophylaxis for surgical site infections in pediatric spinal surgery: a systematic review and network meta-analysis

OBJECTIVE

Postoperative infections in pediatric spinal surgery commonly occur and necessitate reoperation(s). However, pediatric-specific infection prophylaxis guidelines are not available. This network meta-analysis compares perioperative prophylaxis methods including Betadine irrigation, saline irrigation, intrawound vancomycin powder, combination therapy (Betadine, vancomycin, gentamicin, and cefuroxime), Betadine irrigation plus vancomycin powder, and no intervention to determine the most efficacious prevention method.

METHODS

A systematic review was performed by searching the PubMed, EBSCO, Scopus, and Web of Science databases for peer-reviewed articles published prior to February 2022 comparing two or more infection prophylaxis methods in patients younger than 22 years of age. Data were extracted for treatment modalities, patient demographics, and patient outcomes such as total number of infections, surgical site infections, deep infections, intraoperative blood loss, operative time, follow-up time, and postoperative complications. Quality and risk of bias was assessed using National Institutes of Health tools. A network meta-analysis was performed with reduction of infections as the primary outcome.

RESULTS

Overall, 10 studies consisting of 5164 procedures were included. There was no significant difference between prophylactic treatment options in reduction of infection. However, three treatment options showed significant reduction in total infection compared with no prophylactic treatment: Betadine plus vancomycin (OR 0.22, 95% CI 0.09-0.54), vancomycin (OR 3.26, 95% CI 1.96-5.44), and a combination therapy (Betadine, vancomycin, gentamicin, and cefuroxime) (OR 0.24, 95% CI 0.07-0.75). P-Score hierarchical ranking estimated Betadine plus vancomycin to be the superior treatment to prevent total infections, deep infections, and surgical site infections (P-score 0.7876, 0.7175, and 0.7291, respectively). No prophylaxis treatment-related complications were reported.

CONCLUSIONS

The results of this network meta-analysis show the strongest support for Betadine plus vancomycin as a method to reduce infections following pediatric spinal surgery. There was heterogeneity among studies and inconsistent outcome reporting; however, three effective treatment options are identified.

Paediatric Spinal Deformity Surgery: Complications and Their Management

Surgical correction of paediatric spinal deformity is associated with risks, adverse events, and complications that must be preoperatively discussed with patients and their families to inform treatment decisions, expectations, and long-term outcomes. The incidence of complications varies in relation to the underlying aetiology of spinal deformity and surgical procedure. Intraoperative complications include bleeding, neurological injury, and those related to positioning. Postoperative complications include persistent pain, surgical site infection, venous thromboembolism, pulmonary complications, superior mesenteric artery syndrome, and also pseudarthrosis and implant failure, proximal junctional kyphosis, crankshaft phenomenon, and adding-on deformity, which may necessitate revision surgery. Interventions included in enhanced recovery after surgery protocols may reduce the incidence of complications. Complications must be diagnosed, investigated and managed expeditiously to prevent further deterioration and to ensure optimal outcomes. This review summarises the complications associated with paediatric spinal deformity surgery and their management.

Treatment of Scoliosis with One‐Stage Posterior Pedicle Screw System by Paraspinal Intermuscular Approach: A Minimum of Two Years of Follow‐Up

Objective

To evaluate the clinical efficacy of the treatment of scoliosis with a pedicle screw system through paraspinal intermuscular approach (PIA).

Methods

This is a retrospective case series study. A total of 10 patients diagnosed with scoliosis had surgical indications and treated with a pedicle screw system in one‐stage posterior surgery by PIA from March 2013 to April 2015 at the First Hospital of Jilin University were enrolled in this study. The average age of the patients was 14.9 years, including one male and nine females. The operative information and surgical results, including Cobb angle correction, correction loss, global balance (including Frontal Plane Balance [FPB] and Sagittal Plane Balance [SPB]), and fusion rate were reviewed. Functional outcomes including visual analog scale (VAS) back pain score, leg pain score, and Scoliosis Research Society‐22 questionnaire (SRS‐22) were used to evaluate the quality of life of patients preoperatively and at last follow‐up.

Results

Each patient was followed up at least six times. The average follow‐up time was 43.2 months. Mean scoliosis and kyphosis improved from 68.5° ± 18.1°to 18.7° ± 11.8° and from 34.4° ± 17.9°to 24.0° ± 6.7°, respectively (p < 0.05); at last follow‐up, it was 20.1° and 24.7°, respectively (p > 0.05). During the follow‐up, mean coronal and sagittal correction loss was 1.4° ± 1.2°and 0.7° ± 0.8°, respectively (p > 0.05). Mean FPB improved from 32.7 to 11.7 mm (p < 0.05); Mean SPB changed from 0.3 to −0.7 mm (p > 0.05). No dural tears were observed during the corrective surgery or wound infection or implant‐related complications. No pseudoarthrosis was identified according to the last follow‐up three‐dimensional (3D) CT scan. All the domains in SRS‐22 questionnaire show statistically significant improvement at the last follow‐up (p < 0.05). The VAS back pain scores improved from a mean preoperative score of 1.7 to a mean postoperative score of 0.2 (p < 0.05).

Conclusion

This original one‐stage posterior PIA is safe and effective in the treatment of scoliosis, which is characterized with less blood loss, shorter operation time, and satisfactory bony fusion.

Epigenetic and Genetic Factors Related to Curve Progression in Adolescent Idiopathic Scoliosis: A Systematic Scoping Review of the Current Literature

Adolescent idiopathic scoliosis (AIS) is a progressive deformity of the spine. Scoliotic curves progress until skeletal maturity leading, in rare cases, to a severe deformity. While the Cobb angle is a straightforward tool in initial curve magnitude measurement, assessing the risk of curve progression at the time of diagnosis may be more challenging. Epigenetic and genetic markers are potential prognostic tools to predict curve progression. The aim of this study is to review the available literature regarding the epigenetic and genetic factors associated with the risk of AIS curve progression. This review was carried out in accordance with Preferential Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The search was carried out in January 2022. Only peer-reviewed articles were considered for inclusion. Forty studies were included; fifteen genes were reported as having SNPs with significant association with progressive AIS, but none showed sufficient power to sustain clinical applications. In contrast, nine studies reporting epigenetic modifications showed promising results in terms of reliable markers. Prognostic testing for AIS has the potential to significantly modify disease management. Most recent evidence suggests epigenetics as a more promising field for the identification of factors associated with AIS progression, offering a rationale for further investigation in this field.

Minimally invasive surgery using posterior-only Pedicle screw fixation in treatment of Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-Analysis

Minimally invasive surgery (MIS) techniques for posterior spine pedicle-screw fusion (PSF) may reduce the AIS surgery invasiveness, although they require a certain degree of patient selection based on the severity of the curve. The aim of this article is to systematically review the Literature to determine efficacy and safety of MIS-PSF in AIS correction, and to compare its outcomes with open-PSF. A systematic search of electronic databases from eligible articles was conducted. Only studies adopting MIS-PSF for AIS were included. Clinical and radiographic outcomes were extracted and summarized. Meta-analyses were performed. P-value < 0.05 was considered significant. Thirteen studies for a total of 635 patients ungergoing MIS-PSF were included in this review. Pre-operative Cobb's angle ranged from 48.3°±4.2° to 59.8°±6.6°, coronal correction from 58.1% to 79.1%, average operative time ranged from 252 to 526.8 min, average estimated blood loss from 138.8 ± 50 to 1250 mL. Sixty-seven complications were recorded (9.9%), with 19 revisions (3.8%), resulting similar to those described in Literature using open-PSF. At meta-analysis, MIS-PSF (321 patients) compared to open-PSF (429 patients) showed lower coronal correction (although no statistically significant difference was found), estimated blood loss and length of hospital stay, but higher operative time. No differences in SRS-22, complications and revision rate were found. In conclusion, open-PSF shows a trend towards higher correction in the coronal plane and requires a shorter operative time when compared to MIS-PSF. It remains the gold standard for AIS correction, although MIS-PSF seems to be a viable and promising technique for selected patients. - KEYWORDS: minimally invasive surgery, minimally invasive techniques, adolescent idiopathic scoliosis, posterior spinal fusion, pedicle-screws-only instrumentation.

A Clinical Risk Model for Surgical Site Infection Following Pediatric Spine Deformity Surgery

BACKGROUND

Despite tremendous efforts, the incidence of surgical site infection (SSI) following the surgical treatment of pediatric spinal deformity remains a concern. Although previous studies have reported some risk factors for SSI, these studies have been limited by not being able to investigate multiple risk factors at the same time. The aim of the present study was to evaluate a wide range of preoperative and intraoperative factors in predicting SSI and to develop and validate a prediction model that quantifies the risk of SSI for individual pediatric spinal deformity patients.

METHODS

Pediatric patients with spinal deformity who underwent primary, revision, or definitive spinal fusion at 1 of 7 institutions were included. Candidate predictors were known preoperatively and were not modifiable in most cases; these included 31 patient, 12 surgical, and 4 hospital factors. The Centers for Disease Control and Prevention definition of SSI within 90 days of surgery was utilized. Following multiple imputation and multicollinearity testing, predictor selection was conducted with use of logistic regression to develop multiple models. The data set was randomly split into training and testing sets, and fivefold cross-validation was performed to compare discrimination, calibration, and overfitting of each model and to determine the final model. A risk probability calculator and a mobile device application were developed from the model in order to calculate the probability of SSI in individual patients.

RESULTS

A total of 3,092 spinal deformity surgeries were included, in which there were 132 cases of SSI (4.3%). The final model achieved adequate discrimination (area under the receiver operating characteristic curve: 0.76), as well as calibration and no overfitting. Predictors included in the model were nonambulatory status, neuromuscular etiology, pelvic instrumentation, procedure time ≥7 hours, American Society of Anesthesiologists grade >2, revision procedure, hospital spine surgical cases <100/year, abnormal hemoglobin level, and overweight or obese body mass index.

CONCLUSIONS

The risk probability calculator encompassing patient, surgical, and hospital factors developed in the present study predicts the probability of 90-day SSI in pediatric spinal deformity surgery. This validated calculator can be utilized to improve informed consent and shared decision-making and may allow the deployment of additional resources and strategies selectively in high-risk patients.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Factors Affecting Operation Duration in Posterior Spinal Fusion (PSF) Using Dual Attending Surgeon Strategy Among Lenke 1 and 2 Adolescent Idiopathic Scoliosis (AIS) Patients

STUDY DESIGN

This was a retrospective study.

SUMMARY OF BACKGROUND DATA

Prolonged operation duration in adolescent idiopathic scoliosis (AIS) surgery was associated with increased perioperative complications. However, the factors affecting operation duration in AIS surgery were unknown.

OBJECTIVE

The aim of the study was to investigate the factors affecting operation duration in posterior spinal fusion (PSF) surgery using a dual attending surgeon strategy among Lenke 1 and 2 AIS patients.

METHODS

In all, 260 AIS patients with Lenke 1 and 2 curves who underwent PSF were retrospectively reviewed. Preoperative and intraoperative factors affecting operation duration such as age, sex, height, weight, body mass index, Risser grade, Lenke subtypes, number of fusion level, number of screws, screw density, wound length, upper and lowest instrumented vertebrae level, preoperative Cobb angle, and flexibility of the major curve were assessed using univariate and multivariate linear regression analyses. Independent factors were determined when P-value <0.05.

RESULTS

The mean operation duration was 122.2±28.6 minutes. Significant independent factors affecting operation duration in PSF among Lenke 1 and 2 AIS patients were Lenke 2 subtypes (β=8.86, P=0.008), number of screws (β=7.01, P<0.001), wound length (β=1.14, P=0.009), and flexibility of the major curve (β=-0.25, P=0.005). The overall model fit was R2=0.525. Operation duration can be predicted using the formula: (8.86×Lenke subtypes)+(7.01×number of screws)+(1.14×wound length)-(0.25×flexibility)-0.54, where Lenke 2=1 and Lenke 1=0.

CONCLUSION

The factors affecting operation duration in PSF among Lenke 1 and 2 AIS patients were Lenke 2 curves, number of screws, wound length, and curve flexibility. The knowledge of these factors enables the spinal deformity surgeons to plan and estimate the operation duration before AIS surgery.

Low BMI (< 10th percentile) increases complications and readmissions after posterior spinal fusion in adolescent idiopathic scoliosis

PURPOSE

While obesity has been shown to predict negative outcomes following PSF in AIS patients, less is known about the effects of low BMI. We sought to elucidate the impact of low BMI on 30-day outcomes in this population.

METHODS

Adolescent idiopathic scoliosis patients undergoing PSF were identified using the 2015-17 ACS-NSQIP-Pediatric database. Patients were placed in underweight (UW, < 10th percentile) and normal weight (NW 10-90th percentile) cohorts based off CDC BMI-to-age growth charts. Demographics, comorbidities, intra-, and postoperative factors were compared via univariate analysis with Benjamini-Hochberg adjustment. Multivariable logistic regression models were generated to assess UW status as a predictor of complications.

RESULTS

Two thousand seven hundred and ninety-nine AIS patients undergoing PSF (NW = 2517, UW = 282) were identified. UW patients were older (15.6 vs. 14.7 years), less female dominant (62.4% vs. 79.5%), and had more pulmonary (2.5% vs. 0.4%) and minor cardiac comorbidities (6% vs. 1.7%) compared to NW patients (p < 0.001). UW patients had a greater percentage blood loss (6.7% vs. 5.3% of total blood volume, p < 0.001) and higher complication (3.9% vs. 1.4%, p = 0.008), pneumonia (1.4% vs. 0.1%, p = 0.006), and readmission (3.5% vs. 1.2%, p = 0.001) rates compared to NW patients. UW status was a predictor of ≥ 15% blood volume loss (adjusted OR = 2.65; 95% CI = 1.76-3.97; p < 0.001), pneumonia (aOR = 6.57; 95% CI = 1.80-24.00; p = 0.004), and hospital readmission (aOR = 2.47; 95% CI = 1.02-6.01; p = 0.046).

CONCLUSION

There is a higher occurrence of complications in UW AIS patients undergoing PSF. Low BMI is an independent predictor of ≥ 15% blood loss, pneumonia, and readmissions. Like their overweight counterparts, underweight AIS patients have an increased postoperative risk for negative complications.

Minimally Invasive Versus Standard Surgery in Idiopathic Scoliosis Patients: A Comparative Study

STUDY DESIGN

Retrospective review of prospective case-control study.

OBJECTIVE

To compare minimally invasive scoliosis surgery (MIS) and posterior spinal fusion (PSF) in a large group of patients.

SUMMARY OF BACKGROUND DATA

MIS, has been shown to have benefits over standard PSF in adolescent idiopathic scoliosis (AIS).

METHODS

Radiographic, clinical, and operative review of a multi-institutional prospective database from 2013 to 2018. MIS patients with minimum 2-year XR follow up were compared with open PSF technique patients.

RESULTS

Four hundred eighty five patients were included; 192 MIS and 293 PSF. Preoperative Cobb (P = 0.231) and kyphosis were similar (P = 0.501). Cobb correction was comparable (P = 0.46), however percent improvement in thoracic kyphosis was significantly higher in MIS (P < 0.001). MIS had significantly lower blood loss (P < 0.001), transfusions (P < 0.001), fixation points (P < 0.001), opioid consumption (P = 0.001), and hospital stay (P < 0.001). Operative time was shorter (P = 0.001) and 30-day complications rate was similar (P = 0.81).

CONCLUSION

This is the largest study comparing the surgical outcomes of MIS and PSF. MIS patients benefit from increased kyphosis, fewer transfusion, lower opioid consumption, and shorter hospital stay with similar Cobb correction. Increased postoperative kyphosis is likely from muscle sparing dissection in MIS.Level of Evidence: 3.

Early and late hospital readmissions in adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective review of a prospectively collected multicenter database.

OBJECTIVES

To identify risk factors for early and late readmission of surgically treated patients with adolescent idiopathic scoliosis (AIS). Specific risk factors associated with readmission in patients with AIS remain poorly understood.

METHODS

Patients with AIS who were operatively treated from 19 centers specializing in the treatment of pediatric spinal deformity were studied. Data from a minimum 2 years of clinical follow-up and any readmission were available for analysis. Characteristics of patients with no readmission, early readmission (< 90 days), and late readmission (> 90 days) were evaluated. Both univariate and multivariate analyses of risk factors for readmission were performed.

RESULTS

2049 patients were included in our cohort, with 1.6% requiring early readmission and 3.3% late readmission. In the multivariate analysis, greater preoperative coronal imbalance was associated with early readmission. Longer operative time was associated with late readmission. Finally, greater preoperative pain (SRS-22 pain scale) was associated with both early and late readmission. GI complications accounted for a higher proportion of early readmissions than previously reported in the literature.

CONCLUSIONS

Preoperative counseling of patients with higher levels of pain and coronal imbalance and the implementation of a thorough postoperative bowel regimen may help optimize patient outcomes.

LEVEL OF EVIDENCE

3.

Perioperative outcome and complications following single-staged Posterior Spinal Fusion (PSF) using pedicle screw instrumentation in Adolescent Idiopathic Scoliosis (AIS): a review of 1057 cases from a single centre

Background

There has been a growing interest in using all pedicle screw construct in posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) surgery in recent years. However, studies focusing on perioperative outcome and complications utilizing only pedicle screw system in AIS population are lacking. This study aims to evaluate perioperative outcomes and to determine the prevalence of major and minor complications following single-staged PSF for AIS.

Methods

In this retrospective study of prospectively collected data, 1057 AIS patients operated between 2012 and 2019 were included. Main outcome measures were operative time, intraoperative blood loss, allogeneic blood transfusion rate, length of hospital stay after surgery, complication rate, and mean drop of haemoglobin (Hb) level. We documented the number of fusion levels, screw density, and postoperative radiographic parameters.

Results

There were 917 females and 140 males. Majority were Lenke 1 curve type (46.9%). Mean age was 15.6 ± 3.7 years, with mean BMI of 18.6 ± 3.2 kg/m². Mean operative time was 146.8 ± 49.4 min. Average intraoperative blood loss was 952.9 ± 530.4 ml with allogeneic blood transfusion rate of 5%. Mean screw density was 1.27 ± 0.21 screws per fusion level. Average hospital stay after surgery was 3.5 ± 0.9 days. Twenty-four complications were documented: twelve superficial infections (1.14%), five transient neurological deficits (0.47%), two deep infections (0.19%), two superior mesenteric artery syndrome, and one case each (0.09%) for massive intraoperative blood loss, intraoperative seizure, and lung atelectasis.

Conclusion

AIS patients treated with single-staged PSF using pedicle screw construct had a 0.95% rate of major complications and 1.32% rate of minor complications. Rate of neurologic complication was 0.47% while non-neurologic postoperative complications was 1.80% with infection being the leading complication at 1.32%.

Perioperative outcome of severe rigid idiopathic scoliosis: Single-staged posterior spinal fusion utilizing a dual attending surgeon strategy. A report of 41 patients

PURPOSE

Various surgical strategies including combined approach and spinal osteotomies in severe rigid scoliosis had been reported with significant perioperative complication rates. The use of single-staged posterior spinal fusion (PSF) utilizing a dual attending surgeon strategy for severe rigid scoliosis has not been widely reported.

METHODS

This was a retrospective study aimed to evaluate the perioperative outcome of single-staged PSF in severe rigid idiopathic scoliosis patients (Cobb angle ≥90° and ≤30% flexibility). Forty-one patients with severe rigid idiopathic scoliosis who underwent single-staged PSF were included. The perioperative outcome parameters were operation duration, intraoperative blood loss, intraoperative hemodynamic parameters, preoperative and postoperative hemoglobin, transfusion rate, patient-controlled anesthesia morphine usage, length of postoperative hospital stay, and perioperative complications. Radiological parameters included preoperative and postoperative Cobb angle, correction rate, side-bending flexibility, and side-bending correction index.

RESULTS

The mean age was 16.9 ± 5.6 years. The mean preoperative Cobb angle was 110.8 ± 12.1° with mean flexibility of 23.1 ± 6.3%. The mean operation duration was 215.5 ± 45.2 min with mean blood loss of 1752.6 ± 830.5 mL. The allogeneic blood transfusion rate was 24.4%. The mean postoperative hospital stay was 76.9 ± 26.7 h. The mean postoperative Cobb angle and correction rate were 54.4 ± 12.8° and 50.9 ± 10.1%, respectively. The readmission rate in this cohort was 2.4%. Four perioperative complications were documented (9.8%), one somatosensory evoke potential signal loss, one superficial infection, one lung collapse, and one superior mesenteric artery syndrome.

CONCLUSIONS

Severe rigid idiopathic scoliosis treated with single-staged PSF utilizing a dual attending surgeon strategy demonstrated an average correction rate of 50.9%, operation duration of 215.5 min, and postoperative hospital stay of 76.9 h with a 9.8% perioperative complication rate.

Etiopathogenesis of adolescent idiopathic scoliosis: Review of the literature and new epigenetic hypothesis on altered neural crest cells migration in early embryogenesis as the key event

Adolescent idiopathic scoliosis (AIS) affects 2-3% of children. Numerous hypotheses on etiologic/causal factors of AIS were investigated, but all failed to identify therapeutic targets and hence failed to offer a cure. Therefore, currently there are only two options to minimize morbidity of the patients suffering AIS: bracing and spinal surgery. From the beginning of 1960th, spinal surgery, both fusion and rod placement, became the standard of management for progressive adolescent idiopathic spine deformity. However, spinal surgery is often associated with complications. These circumstances motivate AIS scientific community to continue the search for new etiologic and causal factors of AIS. While the role of the genetic factors in AIS pathogenesis was investigated intensively and universally recognized, these studies failed to nominate mutation of a particular gene or genes combination responsible for AIS development. More recently epigenetic factors were suggested to play causal role in AIS pathogenesis. Sharing this new approach, we investigated scoliotic vertebral growth plates removed during vertebral fusion (anterior surgery) for AIS correction. In recent publications we showed that cells from the convex side of human scoliotic deformities undergo normal chondrogenic/osteogenic differentiation, while cells from the concave side acquire a neuronal phenotype. Based on these facts we hypothesized that altered neural crest cell migration in early embryogenesis can be the etiological factor of AIS. In particular, we suggested that neural crest cells failed to migrate through the anterior half of somites and became deposited in sclerotome, which in turn produced chondrogenic/osteogenic-insufficient vertebral growth plates. To test this hypothesis we conducted experiments on chicken embryos with arrest neural crest cell migration by inhibiting expression of Paired-box 3 (Pax3) gene, a known enhancer and promoter of neural crest cells migration and differentiation. The results showed that chicken embryos treated with Pax3 siRNA (microinjection into the neural tube, 44 h post-fertilization) progressively developed scoliotic deformity during maturation. Therefore, this analysis suggests that although adolescent idiopathic scoliosis manifests in children around puberty, the real onset of the disease is of epigenetic nature and takes place in early embryogenesis and involves altered neural crest cells migration. If these results confirmed and further elaborated, the hypothesis may shed new light on the etiology and pathogenesis of AIS.

Predictive factors for intraoperative blood loss in surgery for adolescent idiopathic scoliosis

Background

Adolescent idiopathic scoliosis (AIS) is a common spinal deformity. Posterior spinal fusion remains an important surgical treatment for AIS. This study aims to determine the predictive factors for intraoperative blood loss in AIS surgery.

Methods

Patients who had undergone posterior spinal fusion for adolescent idiopathic scoliosis in a single university hospital were reviewed over a 7-year period. Predictive factors for intra-operative blood loss were studied by multivariate analysis to derive a regression model. Receiver operating characteristic analysis was performed to determine the cut-off values of factors contributing to significant intraoperative blood loss (≥500 ml).

Results

Two hundred and twelve patients were included. Intraoperative blood loss was found to be correlated with gender (r_s = 0.30 (0.17–0.43)), preoperative hemoglobin level (r_s = 0.20 (0.04–0.31)), preoperative Cobb angle (r_s = 0.20 (0.02–0.29)), number of fused levels (r_s = 0.46 (0.34–0.58)), operation duration (r_s = 0.65 (0.54–0.75)), number of anchors (r_s = 0.47 (0.35–0.59)), and p-value ranged from < 0.001 to < 0.05. Significant intraoperative blood loss was influenced by the male gender, operation duration greater than 257.5 min and more than 10 anchors used.

Conclusions

Male gender, increased operation duration and higher number of anchors predicted higher intra-operative blood loss.

The Effects of Pulmonary Risk Factors on Hospital Resource Use After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis Correction

OBJECTIVE

The aim of this study was to determine the impact of preoperative pulmonary risk factors (PRFS) on surgical outcomes after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS).

METHODS

A retrospective cohort study was performed using the American College of Surgeons National Surgical Quality Improvement Program-Pediatric database from 2016 to 2018. All pediatric patients with AIS undergoing PSF were identified. Patients were then categorized by whether they had recorded baseline PRF or no-PRF. Patient demographics, comorbidities, intraoperative variables, complications, length of stay, discharge disposition, and readmission rate were assessed.

RESULTS

A total of 4929 patients were identified, of whom 280 (5.7%) had baseline PRF. Compared with the no-PRF cohort, the PRF cohort had higher rates of complications (PRF, 4.3% vs. no-PRF, 2.2%; P = 0.03) and longer hospital stays (PRF, 4.6 ± 4.3 days vs. no-PRF, 3.8 ± 2.3 days; P < 0.001), yet, discharge disposition was similar between cohorts (P = 0.70). Rates of 30-day unplanned readmission were significantly higher in the PRF cohort (PRF, 6.3% vs. no-PRF, 2.7%; P = 0.009), yet, days to readmission (P = 0.76) and rates of 30-day reoperation (P = 0.16) were similar between cohorts. On multivariate analysis, PRF was found to be a significant independent risk factor for longer hospital stays (risk ratio, 0.74; 95% confidence interval, 0.44-1.04; P < 0.001) but not postoperative complication or 30-day unplanned readmission.

CONCLUSIONS

Our study showed that PRF may be a risk factor for slightly longer hospital stays without higher rates of complication or unplanned readmission for patients with AIS undergoing PSF and thus should not preclude surgical management.

The risks, reasons, and costs for 30- and 90-day readmissions after fusion surgery for adolescent idiopathic scoliosis

OBJECTIVE

With the continued evolution of bundled payment plans, there has been a greater focus within orthopedic surgery on quality metrics up to 90 days of care. Although the Centers for Medicare and Medicaid Services does not currently penalize hospitals based on their pediatric readmission rates, it is important to understand the drivers for unplanned readmission to improve the quality of care and reduce costs.

METHODS

The National Readmission Database provides a nationally representative sample of all discharges from US hospitals and allows follow-up across hospitals up to 1 calendar year. Adolescents (age 10-18 years) who underwent idiopathic scoliosis surgery from 2012 to 2015 were included. Patients were separated into those with and those without readmission within 30 days or between 31 and 90 days. Demographics, operative conditions, hospital factors, and surgical outcomes were compared using the chi-square test and t-test. Independent predictors for readmissions were identified using stepwise multivariate logistic regression.

RESULTS

A total of 30,677 patients underwent adolescent idiopathic scoliosis surgery from 2012 to 2015. The rates of 30- and 90-day readmissions were 2.9% and 1.4%, respectively. The mean costs associated with the index admission and 30- and 90-day readmissions were $60,680, $23,567, and $16,916, respectively. Common risk factors for readmissions included length of stay > 5 days, obesity, neurological disorders, and chronic use of antiplatelets or anticoagulants. The index admission complications associated with readmissions were unintended durotomy, syndrome of inappropriate antidiuretic hormone, and superior mesenteric artery syndrome. Hospital factors, discharge disposition, and operative conditions appeared to be less important for readmission risk. The top reasons for 30-day and 90-day readmissions were wound infection (34.7%) and implant complications (17.3%), respectively. Readmissions requiring a reoperation were significantly higher for those that occurred between 31 and 90 days after the index readmission.

CONCLUSIONS

Readmission rates were low for both 30- and 90-day readmissions for adolescent idiopathic scoliosis surgery patients. Nevertheless, readmissions are costly and appear to be associated with potentially modifiable risk factors, although some risk factors remain potentially unavoidable.

Using a dedicated spine radiology technologist is associated with reduced fluoroscopy time, radiation dose, and surgical time in pediatric spinal deformity surgery

STUDY DESIGN

Retrospective comparative study OBJECTIVES: The goal of this study was to investigate fluoroscopy time and radiation exposure during pediatric spine surgery using a dedicated radiology technologist with extensive experience in spine operating rooms. Repetitive use of intraoperative fluoroscopy during posterior spinal fusion (PSF) exposes the patient, surgeon, and staff to radiation.

METHODS

Retrospective review was conducted on patients with posterior spinal fusion (PSF) of ≥ 7 levels for adolescent idiopathic scoliosis (AIS) at a pediatric hospital from 2015 to 2019. Cases covered by the dedicated radiology technologist (dedicated group) were compared to all other cases (non-dedicated group). Surgical and radiologic variables were compared between groups.

RESULTS

230 patients were included. 112/230 (49%) were in the dedicated group and 118/230 (51%) were in the non-dedicated group. Total fluoroscopy time was significantly reduced in cases with the dedicated technologist (46 s) compared to those without (69 s) (p = 0.001). Radiation dose area product (DAP) and air kerma (AK) were reduced by 43% (p < 0.001) and 42% (p < 0.001) in the dedicated group, respectively. The dedicated group also had reduced total surgical time (4.1 vs. 3.5 h; p < 0.001) and estimated blood loss (447 vs. 378 cc (; p = 0.02). Multivariate regression revealed that using a dedicated radiology technologist was independently associated with decreased fluoroscopy time (p = 0.001), DAP (p < 0.001), AK (p < 0.001), surgical time (p < 0.001), and EBL (p = 0.02).

CONCLUSIONS

In AIS patients undergoing PSF, using a dedicated radiology technologist was independently associated with significant reductions in fluoroscopy time, radiation exposure, surgical time, and EBL. This adds to the growing body of research demonstrating that the experience level of the team-not just that of the surgeon-is necessary for optimal outcomes.

LEVEL OF EVIDENCE

III.

Is it feasible to implement a rapid recovery pathway for adolescent idiopathic scoliosis patients undergoing posterior spinal instrumentation and fusion in a single-payer universal health care system?

PURPOSE

The purpose of this project was to determine if it is feasible to implement a rapid recovery pathway (RRP) for the surgical treatment of adolescent idiopathic scoliosis (AIS) within a single-payer universal healthcare system while simultaneously decreasing length of stay (LOS) without increasing post-operative complications.

METHODS

A retrospective analysis was completed for all patients who underwent posterior spinal fusion for AIS at a tertiary children's hospital in Canada between March 2010 and February 2019, with date of implementation of the RRP being March 1st, 2015. Patient demographic information was collected along with a variety of outcome variables including: LOS, wound complication, infection, 30-day return to the OR, 30-day emergency department visit, and 30-day hospital readmission. An interrupted time series analysis was utilized to determine if any benefits were associated with the implementation of the RRP.

RESULTS

A total of 244 patients were identified, with 113 patients in the conventional pathway and 131 in the RRP. No significant differences in demographic features or post-operative complications were found between the two cohorts (p > 0.05). Using a robust linear time series model, LOS was found to be significantly shorter in the RRP group, with the average LOS being 5.2 [95% IQR 4.3-6.1] days in the conventional group and 3.4 [95% IQR 3.3-3.5] days in the RRP group (p < 0.05).

CONCLUSION

This study shows that it is possible to implement a RRP for the surgical treatment of AIS within a single-payer universal healthcare system. Use of the pathway can effectively reduce hospital LOS without increasing the risk of developing a post-operative complication. This has the upside potential to reduce healthcare and family costs.

LEVEL OF EVIDENCE

Therapeutic III.

Comparing short-term AIS post-operative complications between ACS-NSQIP and a surgeon study group

STUDY DESIGN

Prospective cohort review.

OBJECTIVE

To compare two AIS databases to determine if a performance improvement-based surgeon group has different outcomes compared to a national database. The American College of Surgeon's National Quality Improvement Program (ACS-NSQIP) and a surgeon study group (SG) collect prospective data on AIS surgery outcomes. NSQIP offers open enrollment to all institutions, and SG membership is limited to 15 high-volume institutions, with a major initiative to improve surgeon performance. While both provide important outcome benchmarks, they may reflect outcomes that are not relatable nationwide.

METHODS

The ASC-NSQIP Pediatric Spine Fusion and SG database were queried for AIS 30- and 90-day complication data for 2014 and 2015. Prospective enrollment and a dedicated site coordinator with rigorous data quality assurance protocols existed for both registries. Outcomes were compared between groups with respect to superficial and deep surgical site infections (SSI), neurologic injury, readmission, and reoperation.

RESULTS

There were a total of 2927 AIS patients included in the ASC-NSQIP data and 721 in the SG database. Total complication rate was 9.4% NSQIP and 3.6% SG. At 90 days, there were fewer surgical site infections reported by SG than ASC-NSQIP (0.6% vs. 1.6%, p = 0.03). Similarly, there were less spinal cord injuries (0.8% vs 1.5%, p = 0.006), 30-day readmissions (0.8% vs. 2.6%, p = 0.002), and 30-day reoperations (0.6% vs. 1.7%, p = 0.02) in the SG cohort.

CONCLUSIONS

Comparison of these two data sets suggests a range of complications and readmission rates, with the SG demonstrating lower values. These results are likely multi-factorial with the performance improvement initiative of the SG playing a role. Understanding the rate and ultimate risk factors for readmission and complications from big data sources has the potential to further drive quality improvement.

LEVEL OF EVIDENCE

III.

From genetics to epigenetics to unravel the etiology of adolescent idiopathic scoliosis

Scoliosis is defined as the three-dimensional (3D) structural deformity of the spine with a radiological lateral Cobb angle (a measure of spinal curvature) of ≥10° that can be caused by congenital, developmental or degenerative problems. However, those cases whose etiology is still unknown, and affect healthy children and adolescents during growth, are the commonest form of spinal deformity, known as adolescent idiopathic scoliosis (AIS). In AIS management, early diagnosis and the accurate prediction of curve progression are most important because they can decrease negative long-term effects of AIS treatment, such as unnecessary bracing, frequent exposure to radiation, as well as saving the high costs of AIS treatment. Despite efforts made to identify a method or technique capable of predicting AIS progression, this challenge still remains unresolved. Genetics and epigenetics, and the application of machine learning and artificial intelligence technologies, open up new avenues to not only clarify AIS etiology, but to also identify potential biomarkers that can substantially improve the clinical management of these patients. This review presents the most relevant biomarkers to help explain the etiopathogenesis of AIS and provide new potential biomarkers to be validated in large clinical trials so they can be finally implemented into clinical settings.

A dual-team approach benefits standard-volume surgeons, but has minimal impact on outcomes for a high-volume surgeon in AIS patients

STUDY DESIGN

Retrospective chart review of prospectively collected data.

OBJECTIVE

This study seeks to evaluate the effect of number of surgeons, surgeon experience, and surgeon volume on AIS surgery. Recent literature suggests that utilizing two surgeons for spine deformity correction surgery can improve perioperative outcomes. However, the surgeon's experience and surgical volume are likely as important.

METHODS

AIS patients undergoing PSF from 2009 to 2019 were included. Patient demographics, X-ray and perioperative outcomes were collected and collated based on primary surgeon. Analysis was performed for single versus dual surgeons, surgeon experience (≤ 10 years in practice), and surgical volume (less/greater than 50 cases/year). Median (IQR) values, Wilcoxon Rank Sums test, Kruskal-Wallis test, and Fisher's exact test were utilized.

RESULTS

519 AIS cases, performed by 4 surgeons were included. Two surgeons were highly experienced, 1 of whom was also high volume. Five cohorts were studied: a single senior high volume (S1) (n = 302), dual-junior surgeons (DJ) (n = 73), dual senior-junior (SJ) (n = 36), dual-senior (DS) (n = 21) and a single senior, standard-volume surgeon alone (S2) (n = 87). Radiographic parameters were similar between the groups (p > 0.05). Preoperative Cobb was significantly higher for DS compared to S1 (p = 0.034) Pre- and post-op kyphosis were similar (p > 0.05). Cobb correction was similar (p > 0.05). Levels fused, fixation points, anesthesia and surgical times were similar (p > 0.05). When the standard-volume surgeon operated with a second surgeon, radiographic parameters were similar (p > 0.05), but anesthesia time, surgical time, and hospital length of stay were significantly shorter (p < 0.05). Additionally, DJ had significantly shorter anesthesia and operative times (p < 0.001) and length of stay (p < 0.001) compared to S2.

CONCLUSION

Standard-volume surgeons have better outcomes with a dual surgeon approach. Junior surgeons benefit operating with an experienced surgeon. A high-volume surgeon, however, does not benefit from a dual surgeon approach.

LEVEL OF EVIDENCE

Level II.

Preoperative Versus Extended Postoperative Antimicrobial Prophylaxis of Surgical Site Infection During Spinal Surgery: A Comprehensive Systematic Review and Meta-Analysis

Introduction

Surgical site infection (SSI) following spinal surgery is a major source of postoperative morbidity. Although studies have demonstrated perioperative antimicrobial prophylaxis (AMP) to be beneficial in the prevention of SSI among spinal surgery patients, consensus is lacking over whether preoperative or extended postoperative AMP is most efficacious. To date, no meta-analysis has investigated the comparative efficacy of these two temporally variable AMP protocols in spinal surgery. We undertook a systemic review and meta-analysis to determine whether extended postoperative AMP is associated with a difference in the rate of SSI occurrence among adult patients undergoing spinal surgery.

Methods

Embase and MEDLINE databases were systematically searched for clinical trials and cohort studies directly comparing SSI rates among adult spinal surgery patients receiving either preoperative or extended postoperative AMP. Quality of evidence of the overall study population was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group approach. Random effects meta-analyses were performed utilizing both pooled and stratified data based on instrumentation use.

Results

Five studies met inclusion criteria. No individual study demonstrated a significant difference in the rate of SSI occurrence between preoperative and extended postoperative AMP protocols. The GRADE quality of evidence was low. Among the overall cohort of 2824 patients, 96% underwent lumbar spinal surgery. Pooled SSI rates were 1.38% (26/1887) for patients receiving extended postoperative AMP and 1.28% (12/937) for patients only receiving preoperative AMP. The risk of SSI development among patients receiving extended postoperative AMP was not significantly different from the risk of SSI development among patients only receiving preoperative AMP [RR (risk ratio), 1.11; 95% CI (confidence interval) 0.53–2.36; p = 0.78]. The difference in risk of SSI development when comparing extended postoperative AMP to preoperative AMP was also not significant for both instrumented (RR, 0.92; 95% CI 0.15–5.75; p = 0.93) and non-instrumented spinal surgery (RR, 1.25; 95% CI 0.49–3.17; p = 0.65). There was no evidence of heterogeneity of treatment effects for all meta-analyses.

Conclusion

Preoperative AMP appears to provide equivalent protection against SSI development when compared to extended postoperative AMP. Prudent antibiotic use is also known to decrease hospital length of stay, healthcare expenditure, and risk of complications. However, until higher-quality evidence becomes available regarding AMP in spinal surgery, surgeons should continue to exercise discretion and clinical judgment when weighing the effects of patient comorbidities and complications before determining the optimal duration of perioperative AMP.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01371-5) contains supplementary material, which is available to authorized users.

Complications following surgery for adolescent idiopathic scoliosis over a 13-year period

AIMS

The purpose of this study was to evaluate the incidence and analyze the trends of surgeon-reported complications following surgery for adolescent idiopathic scoliosis (AIS) over a 13-year period from the Scoliosis Research Society (SRS) Morbidity and Mortality database.

METHODS

All patients with AIS between ten and 18 years of age, entered into the SRS Morbidity and Mortality database between 2004 and 2016, were analyzed. All perioperative complications were evaluated for correlations with associated factors. Complication trends were analyzed by comparing the cohorts between 2004 to 2007 and 2013 to 2016.

RESULTS

Between 2004 and 2016, a total of 84,320 patients were entered into the database. There were 1,268 patients associated with complications, giving an overall complication rate of 1.5%. Death occurred in 12 patients (0.014%). The three most commonly reported complications were surgical site infection (SSI) (441 patients; 0.52%), new neurological deficit (293; 0.35%), and implant-related complications (172; 0.20%). There was a statistically significant but weak correlation between the occurrence of a SSI and the magnitude of the primary curve (r = 0.227; p < 0.001), and blood loss in surgery (r = 0.111; p = 0.038), while the occurrence of a new neurological deficit was correlated statistically significantly but weakly with age at surgery (r = 0.147; p = 0.004) and magnitude of the primary curve (r = 0.258; p < 0.001). The overall complication rate decreased from 4.95% during 2004 to 2007 to 0.98% during 2013 to 2016 (p = 0.023).

CONCLUSION

An overall complication rate of 1.5% was found in our series after surgery for AIS, with a reduction of complication rates found in the second period of the analysis. Cite this article: Bone Joint J 2020;102-B(4):519-523.

Dedicated spine nurses and scrub technicians improve intraoperative efficiency of surgery for adolescent idiopathic scoliosis

STUDY DESIGN

Retrospective comparative study.

OBJECTIVE

To determine how the use of dedicated spine surgical nurses and scrub technicians impacted surgical outcomes of posterior spinal fusions for adolescent idiopathic scoliosis (AIS). Dedicated team approaches to surgery have been shown to improve surgical outcomes. However, their study on orthopaedics and spine surgery is limited.

METHODS

A retrospective review of all patients who underwent a primary posterior spinal fusion of seven or more levels for AIS at a tertiary care pediatric hospital with a minimum of 2 years of follow-up from 2006 to 2013 was conducted. Our institution had dedicated spine surgeons and anesthesiologists throughout the study period, but use of dedicated spine nurses and scrub technicians was variable. The relationship between the proportion of nurses and scrub technicians that were dedicated spine and surgical outcome variables was examined. A multiple regression was performed to control for the surgeon performing the case and the start time.

RESULTS

A total of 146 patients met criteria. When teams were composed of < 60% dedicated spine nurses and scrub technicians, there was 34 min more total OR time (p = .008), 27 min more surgical time (p = .037), 7 min more nonsurgical OR time (p = .030), 30% more estimated blood loss (EBL) (p = .013), 27% more EBL per level instrumented (p = .020), 113% more allogeneic transfusion (p = .006), and 104% more allogeneic transfusion per level instrumented (p = .009). There was no significant difference in length of stay, unplanned staged procedures, surgical site infection, reoperation, or major medical complications.

CONCLUSIONS

Performing posterior spinal fusions for AIS patients with dedicated spine nurses and scrub technicians is associated with a significant decrease in total OR time, blood loss, and transfusion rates.

LEVEL OF EVIDENCE

III.

Risk Factors Associated with Surgical Site Infection in Pediatric Patients Undergoing Spinal Deformity Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Considerable variation exists in surgical site infection (SSI) prevention practices for pediatric patients undergoing spinal deformity surgery, but the incidence of SSI has been reported to remain high in the United States. The literature reports various risk factors associated with SSI but findings are inconsistent. The purpose of this systematic review and meta-analysis was to assess the published literature investigating associations between various risk factors and SSI in pediatric patients undergoing spinal surgery.

METHODS

The systematic review and the meta-analysis were conducted according to Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) guidelines among peer-reviewed journals published in English between January 2000 and April 2019. Studies that involved pediatric patients with spinal deformity undergoing surgical procedures in North America and assessed risk factors for SSI were included. The quality of individual studies was assessed, and weighted risk ratios and mean differences were calculated for each risk factor.

RESULTS

Of 763 potential articles identified, 13 met inclusion criteria; 7 studies were rated as average and 6, as poor quality based on the quality checklist. The meta-analysis demonstrated that the SSI risk increased by the following factors: 2.53 (95% confidence interval [CI], 1.26 to 5.10) for overweight to obese patients compared with patients with normal weight, 2.84 (95% CI, 1.67 to 4.81) for patients with a neuromuscular etiology compared with non-neuromuscular etiology, 1.69 (95% CI, 1.41 to 2.02) for patients with a gastrostomy tube (G-tube) compared with those without, 3.45 (95% CI, 2.08 to 5.72) for nonambulatory patients compared with ambulators, and 3.39 (95% CI, 2.38 to 4.83) for patients with pelvic instrumentation compared with those without. Patients who developed SSI also had 158.38 mL (95% CI, 46.78 to 269.97 mL) greater estimated blood loss compared with those who did not.

CONCLUSIONS

Despite the limited quality of the available studies and wide variety of populations and outcome definitions, evidence suggests that overweight to obese status, neuromuscular etiology, use of a G-tube, nonambulatory status, instrumentation to the pelvis, and greater estimated blood loss are risk factors for SSI. The use of a common SSI definition and strong methodology are warranted for future studies.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete list of levels of evidence.

Seromas Following Pediatric Spinal Deformity Surgery: Is Operative Management Necessary?

BACKGROUND

Seromas are known complications after pediatric spinal deformity surgery. Although many surgeons perform an early debridement to prevent deep surgical site infections (SSIs), a less invasive approach to seroma management has not been studied. We hypothesized that a conservative approach to seroma management would be safe and yield equivalent outcomes.

METHODS

We performed a retrospective review of patients who developed a postoperative seroma with or without nonpurulent drainage. Inclusion criteria were patients below 21 years who underwent primary posterior spinal fusion from 1996 to 2016 and developed a postoperative wound seroma. Seromas were clinically defined as an afebrile patient with a fluid collection that was soft and nontender to palpation and without induration or erythema. Growing spine surgeries and revision procedures were excluded from this study.

RESULTS

Twenty-five of 790 total patients with a mean follow-up of 57.8 months (±48.5 mo) developed a seroma. Seromas were identified at a mean of 13.6 days postoperatively and resolved after a mean of 12.2 days following the presentation. Seromas occurred in 12 patients with idiopathic scoliosis, 12 with neuromuscular scoliosis, and 1 patient with Scheuermann kyphosis. All cases were managed conservatively with monitoring of the incision without an operative procedure. In cases of spontaneous drainage, a sterile dressing was applied to the wound and changed as needed until drainage ceased. Two patients underwent bedside needle aspiration and 5 patients received prophylactic antibiotics at the treating surgeon's discretion. All cases resolved spontaneously without development of an acute SSI. Three cases subsequently developed a late SSI (range, 18 to 38 mo postoperatively). Two had idiopathic scoliosis and 1 had neuromuscular scoliosis. None of these seromas drained spontaneously.

CONCLUSIONS

Conservative management of postoperative seromas after pediatric spinal deformity surgery is appropriate. It is unclear if seromas contributed to the development of the 3 late infections. Further studies are needed regarding the relationship of late infections in seroma patients.

LEVEL OF EVIDENCE

Level IV-case series.

Back-to-Back Surgeries in AIS Patients Can be Performed Safely Without Compromising Radiographic or Perioperative Outcomes: A 10-year Review

STUDY DESIGN

A retrospective chart review of prospectively collected data.

OBJECTIVE

The aim of this study was to determine whether back-to-back scoliosis surgeries can be performed safely without compromising outcomes and the reproducibility of the practice between institutions.

SUMMARY OF BACKGROUND DATA

During the summer, spinal surgeons will often book multiple cases in one day. The complexity and demands of spinal fusion surgery call into question the safety. Change of operating room staff including anesthesiologists, nurses, and neurologists may introduce new risks.

METHODS

From 2009 to 2018, index AIS surgeries were included. In Groups 1, 2, and 3, surgeries were performed by a single surgeon. In Group 4, they were performed by other institutional surgeons. Group 1: first surgery of the day, Group 2: second surgery of the day, Group 3: only surgery of the day, Group 4: only surgery of the day by different institutional surgeon. Additional analysis was done to determine reproducibility after a surgeon was moved from Institution 1 to Institution 2.

RESULTS

Five hundred sixty-seven AIS patients were analyzed. Group 1 patients had similar radiographic outcomes compared with Group 2 (P > 0.05). Surgical time was similar (P = 0.51), but significantly more levels fused (P = 0.01). Compared with Group 3, Group 2 had a smaller preoperative Cobb (P = 0.02), shorter surgeries (P < 0.001), and length of stay (P = 0.04) but similar complication rate (P = 1). Compared with Group 4, Group 2 had smaller preoperative Cobb (P < 0.001), shorter surgery, and lower complication rate (P = 0.03). When determining reproducibility, institution 2 patients had significantly less blood loss, shorter surgeries, and shorter lengths of stay (P < 0.05).

CONCLUSION

Although long and involved, back-to-back AIS surgeries do not compromise radiographic or perioperative outcomes. Changes in operating team do not appear to impact safety, efficiency, or outcomes. This study also found that the practice is reproducible between institutions.

LEVEL OF EVIDENCE

3.

Disaster Scenarios in Spine Surgery: A Survey Analysis

STUDY DESIGN

Survey analysis among spine surgeons.

OBJECTIVE

To identify current consensus and discrepancies in managing adverse intraoperative events among spine surgeons.

SUMMARY OF BACKGROUND DATA

Major intraoperative events are not commonly the subject of formal medical training, in part due to the relative paucity of their occurrence and in part due to an insufficient evidence base. Given the clinical impact of appropriate complication management, it is important to identify where surgeons may be able to improve decision making when choosing interventions.

METHODS

A survey was created including five hypothetical unpredicted scenarios affecting different organ systems to assess the respondents' preferred reactions. The five clinical vignettes that were selected by the researchers involved: 1) loss of spinal signals in neuro-monitoring, 2) prone position cardiac arrest, 3) prone position hypoxia during thoracic corpectomy and instrumentation, 4) supine cervical vertebral artery injury, and 5) sudden onset hypotension in major prone position reconstructive spine surgery. Twenty-eight surveys (Spine Fellows n = 11; Spine surgeon Faculty n = 17) were completed and returned to the investigators. Results were sorted and ranked according to the frequency each action was identified as a top five choice.

RESULTS

Following formal statistical evaluation loss of signals in neuro-monitoring had the statistically significantly most uniform response while the scenario involving cardiac compromise had the most heterogeneous. Many "best" responses had near or complete consensus while some "distractor" possibilities that could harm a patient were also selected by the respondents.

CONCLUSION

The heterogeneity of responses in the face of "disaster scenario" intraoperative events shows there is room for more thorough and directed education of spine surgeons during training. As surgical teaching moves toward increased use of patient simulation and situational learning, these vignettes hopefully serve to provide direction for training future spine surgeons on how best to approach difficult situations.

LEVEL OF EVIDENCE

4.