Perioperative Outcome of Single Stage Posterior Spinal Fusion for Severe Adolescent Idiopathic Scoliosis (AIS) (Cobb Angle ≥90°): The Role of a Dual Attending Surgeon Strategy

Two AIS Cases, 2 Surgeons, 1 Operating Room, 1 Day: Faster and Safer Than 1 Case in a Day

BACKGROUND

To lessen surgical times for patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal instrumentation and fusion (PSIF), our department developed a quality improvement initiative where 2 AIS cases were completed in 1 day by the same 2 surgeons operating together in 1 operating room (OR). We describe the results of this initiative, comparing operative times and outcomes to cases of these surgeons operating individually.

METHODS

From 2017 to 2023, patients aged 10 to 18 years with AIS undergoing PSIF were prospectively enrolled for "Two Spine Tuesday." Patients were matched by age, sex, curve severity, and number of levels fused to historical AIS controls. Outcomes included surgery time, total OR time, estimated blood loss (EBL), volume of cell saver transfused, allogenic blood transfusion, length of stay, 90-day readmissions, Clavien-Dindo-Sink Complication Classification System complication rates, and percentage who achieved the minimal clinically important difference (MCID) for SRS-22.

RESULTS

Fifty-five patients composing the 2-spine group (group 2) were compared with 55 historical sex-matched and age-matched controls (group 1). Major coronal curve and average number of levels fused were similar between groups. Overall surgery time (203 vs. 296 min, P<0.001), total OR time (P<0.001), and EBL (400 vs. 550 mL, P<0.001) were lower for group 2. Group 2 had fewer complications [n=17 (31%) vs. n=28 (51%), P=0.03].

CONCLUSIONS

Performing 2 AIS cases in 1 OR by 2 surgeons the same day resulted in shorter surgery times, less total time in the operating room, lower complication rates, and less blood loss compared with single-surgeon matched controls.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

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.

Diagnostic utility of different types of somatosensory evoked potential changes in pediatric idiopathic scoliosis correction surgery

PURPOSE

To evaluate the diagnostic accuracy of intraoperative somatosensory evoked potential (SSEP) monitoring and types of SSEP changes in predicting the risk of postoperative neurological outcomes during correction surgery for idiopathic scoliosis (IS) in the pediatric age group (≤ 21 years).

METHODS

Database review was performed to identify literature on pediatric patients with IS who underwent correction with intraoperative neuromonitoring. The sensitivity, specificity, and diagnostic odds ratio (DOR) of transient and persistent SSEP changes and complete SSEP loss in predicting postoperative neurological deficits were calculated.

RESULTS

Final analysis included 3778 patients. SSEP changes had a sensitivity of 72.9%, specificity of 96.8%, and DOR of 102.3, while SSEP loss had a sensitivity of 41.8%, specificity of 99.3%, and DOR of 133.2 for predicting new neurologic deficits. Transient and persistent SSEP changes had specificities of 96.8% and 99.1%, and DORs of 16.6 and 59, respectively.

CONCLUSION

Intraoperative SSEP monitoring can predict perioperative neurological injury and improve surgical outcomes in pediatric scoliosis fusion surgery.

LEVEL OF EVIDENCE

Level 2. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Risk Quantification Reference Table for Progressed Adolescent Idiopathic Scoliosis Surgery: An Exact Case Matched Outcomes Analysis

STUDY DESIGN

Retrospective Exact Matched case-control study.

OBJECTIVES

Surgical treatment delay in AIS due to family preferences is common. This study aims to quantify the increase in risks as the Cobb angle increases and provide a Quantifiable Risk Reference Table that can be utilized for counseling.

METHODOLOGY

AIS patients were divided into 3 groups: Group A: Cobb angle 50-60°, Group 61-70°, and Group CFinal ≥80°. Each patient in Group CFinal who had curve progression were then traced-back-in-time (TBIT) to review the clinical data at earlier presentations at 50-60° (C1), and 61-70° (C2). Patient demographics, radiological, operative, and outcomes data were compared between Group A vs C1 and Group B vs Group C2.

RESULTS

A total of 614 AIS surgeries were reviewed. Utilizing the EM technique, a total of 302 AIS patients were recruited. There were 147, 111, 31, and 32 patients matched in Groups A, B, C1, and C2, respectively. C2 Final patients had 34% curve pattern change, 23.2% higher incidence of requiring two surgeries, and 17.3% increase in complications. There was a statistically significant increase of 2.4 spinal levels fused, 12% increase in implant density, 35% increase in operative time, 97% increase in intra-operative blood loss, 10% loss of scoliosis correction, 40% longer hospitalization stay, and 36% increase in costs for patients who had curve progression.

CONCLUSION

This study is the first to use a homogenously matched AIS cohort to provide a Quantifiable Risk Reference Table. The Risk Table provides essential knowledge for treating physicians when counseling AIS patients.

Utilizing two surgeons for neuromuscular scoliosis suggests improved operative efficiency

PURPOSE

Neuromuscular scoliosis (NMS) patients tend to have significant comorbidities with complex medical and surgical histories. When undergoing posterior spinal fusion (PSF), NMS risks can be much higher than the idiopathic population. This study aimed to identify the impact of two experienced pediatric cosurgeons (CS) compared to a single spine surgeon (SS) on the intra- and postoperative results of NMS PSF.

METHODS

A database of NMS patients who had undergone PSF 2016-2021 identified 53 patients, of which 32 were CS, while 21 were SS. Patients' sex, age, weight, diagnosis, curve severity, fusion performed, estimated blood loss (EBL), transfusion rates, hemoglobin, anesthesia and surgical times, length of stay, and complications were collected.

RESULTS

Patient demographics were similar between groups. Curves were more severe in the CS group (p = 0.013). Intraoperatively, CS patients underwent larger corrections (p = 0.089) but in significantly shorter anesthetic (p = 0.0018) and operative (p = 0.0025) times. Blood loss and transfusions were similar. Postoperatively, intensive-care unit (ICU) admission and length of stay (LOS) were similar, but SS had higher rates of both unplanned ICU admissions (p = 0.36) and 30 day readmissions (p = 0.053). Complications overall were similar between the groups both within 30 days (p = 0.40) and in the short-term period (31-90 days, p = 0.76), though the CS cohort had less Grade 2 immediate postoperative pulmonary complications (p = 0.16).

CONCLUSION

Utilizing CS for NMS PSF has been found to reduce operative times. Downstream, additional potential impacts trended toward fewer unplanned ICU admissions, less-frequent postoperative pulmonary complications, and reduced 30-day readmission rates.

An Examination of the Number of Adolescent Scoliotic Curves That Are Braceable at First Presentation to a Scoliosis Service

Adolescent idiopathic scoliosis (AIS) affects between 0.5% and 5.2% of adolescents and is progressive in two-thirds of cases. Bracing is an effective non-operative treatment for AIS and has been shown to prevent up to 72% of curves from requiring surgery. This paper explores the presentation of AIS in the UK and identifies who would be suitable for bracing, as per guidelines published by the Scoliosis Research Society (SRS) and British Scoliosis Society (BSS), through curve severity and skeletal maturity at presentation. There were 526 patients with AIS eligible for inclusion across three tertiary referral centres in the UK. The study period was individualised to each centre, between January 2012 and December 2021. Only 10% were appropriate for bracing via either SRS or BSS criteria. The rest were either too old, skeletally mature or had a curve size too large to benefit. By the end of data collection, 38% had undergone surgery for their scoliosis. In the UK, bracing for AIS is only suitable for a small number at presentation. Future efforts to minimise delays in specialist review and intervention will increase the number of those with AIS suitable for bracing and reduce the number and burden of operative interventions for AIS in the UK.

Hospital Burdens of Patients With Cerebral Palsy Undergoing Posterior Spinal Fusion for Scoliosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Many patients undergoing posterior spinal fusion (PSF) for scoliosis have concurrent cerebral palsy (CP), which is associated with many medical comorbidities and inherent operative risk. We aimed to quantify the contribution of CP to increased cost, length of stay (LOS), and complication rates in patients with scoliosis undergoing PSF.

METHODS

Using the National Inpatient Sample database, we collected data regarding patient demographics, hospital characteristics, comorbidities, in-hospital complications, and mortality. Primary outcomes included complications, hospital LOS, and total hospital costs. Multivariate regression models assessed the contribution of CP to in-hospital complications, discharge status, and mortality. Linear regression identified the contribution of a diagnosis of CP on hospital LOS and inflation-adjusted cost.

RESULTS

Cerebral palsy was an independent predictor of several complications. The most striking differences were seen for mortality (odds ratio [OR]: 3.40, P < .001), a postoperative requirement for total parenteral nutrition (OR: 3.16, P < .001), urinary tract infection (OR: 2.75, P < .001), surgical site infection (OR: 2.67, P < .001), and pneumonia (2.21, P < .001). Patients with CP ultimately cost an additional $13 482 (P < .001) with a 2.07-day greater LOS (P < .001) than patients without CP.

CONCLUSION

Most complications were seen in higher rates in the CP cohort, with higher cost and LOS in patients with CP versus those with idiopathic scoliosis (IS). Our findings represent important areas of emphasis during preoperative consultations with patients with CP and their families. Extra care in patient selection and multifaceted treatment protocols should continue to be implemented with further investigation on how to mitigate common complications.

Severe Lenke 1 and 2 adolescent idiopathic scoliosis had poorer perioperative outcome, higher complication rate, longer fusion and higher operative cost compared to non-severe scoliosis

PURPOSE

To compare the perioperative outcome and operative cost of posterior spinal fusion (PSF) surgery between severe and non-severe Lenke 1 and 2 adolescent idiopathic scoliosis (AIS) patients.

METHODS

A total of 509 AIS patients who underwent single-staged PSF between 2013 and 2020 were reviewed. Fifty-four severe scoliosis patients (Cobb angle ≥ 90°) were categorized into Gp1, and 455 non-severe scoliosis (Cobb angle < 90°) patients into Gp2. Propensity score matching (PSM) analysis using one-to-one nearest neighbor matching and match tolerance of 0.001 were performed. Outcome measures were operative time, intraoperative blood loss (IBL), allogeneic transfusion rate, perioperative complication, length of stay, fusion level, number of screws used, postoperative Cobb angle, correction rate (CR), side bending correction index (SBCI) and operative cost.

RESULTS

From the PSM analysis, 35 patients from each group were matched. The operative time was 155.9 ± 41.4 and 130.0 ± 30.3 min for Gp1 and Gp2, respectively (p = 0.004). The IBL was 1349.2 ± 1019.0 and 781.9 ± 325.1 mLs for Gp1 and Gp2, respectively (p = 0.003). Fusion level (12.5 ± 0.8 vs. 11.2 ± 1.3, p < 0.001) and number of screws used (16.4 ± 1.6 vs. 14.6 ± 1.4, p < 0.001) were higher in Gp1. Four perioperative complications were observed in Gp1 compared to none in Gp2 (p < 0.039). Gp1 had larger postoperative Cobb angle (p < 0.001), lower CR (p = 0.005) and higher SBCI (p < 0.001). The operative cost was higher in Gp1 (p < 0.001).

CONCLUSIONS

Severe Lenke 1 and 2 AIS patients had poorer perioperative outcome, higher complication rate, longer fusion and higher operative cost than non-severe AIS.

Single- versus Dual-Attending Surgeon Approach for Spine Deformity: A Systematic Review and Meta-Analysis

BACKGROUND

Surgical management of spine deformity is associated with significant morbidity. Recent literature has inconsistently demonstrated better outcomes after utilizing 2 attending surgeons for spine deformity.

OBJECTIVE

To conduct a systematic review and meta-analysis on studies reporting outcomes following single- vs dual-attending surgeons for spine deformity.

METHODS

MEDLINE, Embase, Web of science, and Cochrane databases were last searched on July 16, 2020. A total of 1013 records were identified excluding duplicates. After screening, 10 studies (4 cohort, 6 case series) were included in the meta-analysis. Random-effect models were used to pool the effect estimates by study design. When feasible, further subgroup analysis by deformity type was conducted.

RESULTS

A total of 953 patients were analyzed. Pooled results from propensity score-matched cohort studies revealed that the single-surgeon approach was unfavorably associated with a nonstatistically significant higher blood loss (mean difference = 421.0 mL; 95% CI: -28.2, 870.2), a statistically significant higher operative time (mean difference = 94.3 min; 95% CI: 54.9, 133), length of stay (mean difference = 0.84 d; 95% CI: 0.46, 1.22), and an increased risk of complications (Mantel-Haenszel risk ratio = 2.93; 95% CI: 1.12, 7.66). Data from pooled case series demonstrated similar results for all outcomes. Moreover, these results did not differ significantly between deformity types (adolescent idiopathic scoliosis and adult spinal deformity).

CONCLUSION

Dual-attending surgeon approach appeared to be associated with reduced operative time, shorter hospital stays, and reduced risk of complications. These findings may potentially improve outcomes in surgical treatment of spine deformity.

Learning Curve for a Dual Attending Surgeon Strategy in Posterior Spinal Fusion (PSF): An Analysis of 105 Severe Adolescent Idiopathic Scoliosis Patients (Cobb Angle ≥90°)

STUDY DESIGN

Retrospective study.

OBJECTIVE

To assess the learning curve of a dual attending surgeon strategy in severe adolescent idiopathic scoliosis patients.

SUMMARY OF BACKGROUND DATA

The advantages of a dual attending surgeon strategy in improving the perioperative outcome in scoliosis surgery had been reported. However, the learning curve of this strategy in severe scoliosis had not been widely studied.

METHODS

A total of 105 patients with adolescent idiopathic scoliosis with Cobb angle of 90° or greater, who underwent posterior spinal fusion using a dual attending surgeon strategy were recruited. Primary outcomes were operative time, total blood loss, allogeneic blood transfusion requirement, length of hospital stay from time of operation and perioperative complications. Cases were sorted chronologically into group 1: cases 1 to 35, group 2: cases 36 to 70, and group 3: case 71 to 105. Mean operative time (≤193.3 min), total blood loss (≤1612.2 mL), combination of both and allogeneic blood transfusion were the selected criteria for receiver operating characteristic analysis of the learning curve.

RESULTS

The mean Cobb angle was 104.5° ± 12.3°. The operative time, total blood loss, and allogeneic blood transfusion requirement reduced significantly for group 1 (220.6 ± 54.8 min; 2011.3 ± 881.8 mL; 12 cases) versus group 2 (183.6 ± 36.7 min; 1481.6 ± 1035.5 mL; 3 cases) and group 1 versus group 3 (175.6 ± 38.4 min; 1343.7 ± 477.8 mL; 3 cases) (P < 0.05). There were six perioperative complications. Fifty-seven cases were required to achieve the preset criteria (mean operative time and mean total blood loss) (area under the curve 0.740; P < 0.001; sensitivity 0.675; specificity 0.662).

CONCLUSION

There was significant improvement in operative time and total blood loss when comparing group 1 versus group 2 and group 1 versus group 3. The cut-off point for the learning curve was 57 cases when the preset criteria were fulfilled (≤193.3 min operative time and ≤1612.2 mL of total blood loss).Level of Evidence: 4.

Predictive factors for correction rate in severe idiopathic scoliosis (Cobb angle ≥ 90°): an analysis of 128 patients

PURPOSE

Knowledge on the factors affecting the correction rate (CR) aids in the surgical planning among severe idiopathic scoliosis (IS) patients. This study aimed to investigate the independent factors affecting CR among patients with severe IS (Cobb angle ≥ 90°) who underwent single-staged posterior spinal fusion (PSF).

METHODS

We retrospectively reviewed 128 severe IS patients who underwent single-staged PSF. Factors including age, height, weight, body mass index, Risser sign, Lenke subtypes, preoperative major Cobb angle, side bending major Cobb angle, side bending flexibility (SBF), motion segments of the major curve, AR curve, number of levels fused, screw density, operative time and postoperative major Cobb angle were analysed using linear regression analysis.

RESULTS

The mean age was 15.5 ± 4.5 years with mean Risser sign of 3.1 ± 1.6. The mean preoperative Cobb, SBF, postoperative Cobb and CR were 102.8 ± 12.3°, 37.5 ± 13.7%, 44.4 ± 13.5° and 57.2 ± 10.8%, respectively. From stepwise multiple linear regression analysis, SBF, Risser sign and AR curve were the independent predictive factors for CR, with R² value of 0.345 (p < 0.001). CR can be predicted using the formula: 47.21 + (0.34 × SBF)-(1.47 × Risser sign) + (3.69 × AR), where AR = 1 and non-AR = 0.

CONCLUSION

The flexibility of the major curve, Risser sign and AR curve were the most important predictors for CR in a single-staged PSF among patients with severe IS.

Perioperative Outcome of Severe Idiopathic Scoliosis (Cobb Angle ≥ 90°): Is There Any Difference Between "Daytime" Versus "After-hours" Surgeries?

STUDY DESIGN

Retrospective study from a prospectively collected database.

OBJECTIVE

To compare the perioperative outcome between after-hours and daytime surgery carried out by a dedicated spinal deformity team for severe Idiopathic Scoliosis (IS) patients with Cobb angle ≥ 90°.

SUMMARY OF BACKGROUND DATA

There were concerns that after-hours corrective surgeries in severe IS have higher morbidity compared to daytime surgeries.

METHODS

Seventy-one severe IS patients who underwent single-staged Posterior Spinal Fusion (PSF) were included. Surgeries performed between 08:00H and 16:59H were classified as "daytime" group and surgeries performed between 17:00H and 06:00H were classified as "after-hours" group. Perioperative outcome parameters were average operation start time and end time, operation duration, intraoperative blood loss, intraoperative hemodynamic parameters, preoperative and postoperative hemoglobin, blood transfusion rate, total patient-controlled anesthesia (PCA) morphine usage, length of postoperative hospitalization, and complications. Radiological variables assessed were preoperative and postoperative Cobb angle, side bending flexibility, number of fusion levels, number of screws used, Correction Rate, and Side Bending Correction Index.

RESULTS

Thirty patients were operated during daytime and 41 patients were operated after-hours. The mean age was 16.1 ± 5.8 years old. The mean operation start time for daytime group was 11:31 ± 2:45H versus 19:10 ± 1:24H for after-hours group. There were no significant differences between both groups in the operation duration, intraoperative blood loss, intraoperative hemodynamic parameters, postoperative hemoglobin, hemoglobin drift, transfusion rate, length of postoperative hospitalization, postoperative Cobb angle, Correction Rate, and Side Bending Correction Index. There were four complications (1 SSEP loss, 1 massive blood loss, and 2 superficial wound infections) with no difference between daytime and after-hours group.

CONCLUSION

After-hours elective spine deformity corrective surgeries in healthy ambulatory patients with severe IS performed by a dedicated spinal deformity team using dual attending surgeon strategy were as safe as those performed during daytime.

LEVEL OF EVIDENCE

4.

Multimodal intraoperative monitoring during surgical correction of scoliosis to avoid neurologic damage

The purpose of this study was to evaluate the application of multimodal intraoperative monitoring (MIOM) system in patients with congenital scoliosis (CS) and adolescent idiopathic scoliosis (AIS).Twelve patients who underwent posterior surgical correction of scoliosis for CS and AIS from June 2014 to July 2018 were enrolled in this study. During the operation, we monitored the functional status of the spinal cord by MIOM. An abnormal somatosensory evoked potential was defined as a prolonged latency of more than 10% or a peak-to-peak amplitude decline of more than 50% when compared to baseline. An abnormal transcranial motor evoked potential (TcMEP) was defined as a TcMEP amplitude decrease of more than 50%. A normal triggered electromyography response, which presented with the absence of an electrical response on stimulation at 8.2 mA, indicated that the pedicle screw was not in contact with the spinal cord or nerve root.A total of 12 patients underwent MIOM surgery, of which 9 patients with negative MIOM had no significant deterioration of neurological function postoperatively, and exhibited satisfactory surgical correction of scoliosis during follow-ups. However, the remaining 3 patients suffered from MIOM events, 2 patients had normal neurological function, and 1 patient had deteriorated neurological function postoperatively.Using MIOM in CS and AIS surgery could promptly detect iatrogenic neurological injury at the early stage. Therefore, rapid response by appropriate intraoperative interventions can be taken to minimize the injury. Besides, stable MIOM recordings encourage surgeons to correct scoliosis even when the Cobb angle of scoliosis was extremely large.