Development and Validation of a Multidomain Surgical Complication Classification System for Adult Spinal Deformity

Outcomes of Lumbosacral Hemivertebra Resection and Short Segmental Fusion to Skeletal Maturity

BACKGROUND

The present study aimed to assess the long-term outcomes of lumbosacral hemivertebra (LSHV) resection and short segmental fusion in a pediatric population and to assess the evolution of deformity curves.

METHODS

Patients who sought medical attention at our institution between 2010 and 2018 were assessed for eligibility. A classification of R10 and U9 or higher for the distal radius and ulna, respectively, was used to indicate maturity. Imaging parameters and quality-of-life scores were recorded at postoperative follow-up visits. Analyses were performed for the entire group and for subgroups of patients with and without a curve progression.

RESULTS

A total of 15 male and 15 female patients were included, with a mean age of 6.9 ± 2.4 years at the time of surgery. The main curve averaged 26.6° ± 6.5° preoperatively, 7.5° ± 4.6° (p < 0.001) at 3 months postoperatively, and 8.6° ± 3.2° (p = 0.205) at the latest follow-up. In the coronal plane, the coronal balance averaged 21.3 ± 16.7 mm preoperatively, 11.4 ± 8.5 mm (p = 0.007) at 3 months postoperatively, and 11.2 ± 8.9 mm (p = 0.858) at the latest follow-up. A total of 7 complications were recorded in 6 patients (20.0%). The Scoliosis Research Society 22-Item Questionnaire (SRS-22) total score (p < 0.001), appearance score (p < 0.001), and satisfaction score (p < 0.001) were all significantly different from preoperatively to postoperatively. Compared with the compensatory curve progression group, the non-progression group had a higher SRS total score (p = 0.013) and satisfaction (p < 0.001).

CONCLUSIONS

For pediatric patients <10 years old, LSHV resection and short segmental fusion could provide correction and global spine balance improvement. However, the observed loss of correction in the compensatory curve in some patients during the follow-up may compromise the satisfaction.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Outcome and complication following single-staged posterior minimally invasive surgery in adult spinal deformity

BACKGROUND

The aging population is experiencing a rising incidence of musculoskeletal problems and degenerative spinal deformities. Adult spinal deformity (ASD) presents challenges, with associated risks in open surgery. Minimally invasive surgery (MIS) is becoming increasingly popular due to its positive outcomes and potential benefits. This study aims to explore the clinical outcome and complications of posterior approach MIS in patients with ASD.

METHODS

We conducted a retrospective analysis of patients with adult spinal deformity who underwent posterior minimally invasive surgery. 46 patients meeting the criteria were identified between June 2017 and September 2023. Comprehensive data were collected, including demographic details, surgical information, full-length radiographic measurements, and visual analog scale (VAS) pain scores. These data were obtained preoperatively, postoperatively, and at the final follow-up.

RESULTS

A total of 46 patients were included in the study, with a mean age of 68.58 years and a minimum follow-up period of 6 months. The mean operative time was 327 min, and the mean blood loss was 307 ml. Preoperative radiographic measurements were as follows: Coronal Cobb angle, 18.60 ± 11.35°; lumbar lordosis (LL), 22.79 ± 21.87°; pelvic incidence (PI), 53.05 ± 14.13°; PI-LL mismatch, 30.26 ± 23.48°; pelvic tilt (PT), 32.53 ± 10.38°; T1 pelvic angle (TPA), 31.91 ± 12.39°; and sagittal vertical axis (SVA), 77.77 ± 60.47 mm. At the final follow-up, coronal Cobb angle was 10.08 ± 6.47° (P <0.0001), LL was 26.16 ± 16.92° (P = 0.4293), PI was 54.17 ± 12.13° (P = 0.6965), PI-LL mismatch was 28.00 ± 17.03° (P = 0.6144), PT was 27.74 ± 10.24° (P = 0.0345), TPA was 25.10 ± 10.95 (P = 0.0090) and SVA was 47.91 ± 46.94 mm (P = 0.0129). Functional outcomes improved as well, with the mean Oswestry Disability Index (ODI) decreasing from 34.9 to 23.6 and the Visual Analog Scale (VAS) score for back pain reducing from 8.4 to 3.4. Surgical complications occurred in 39.1% of cases, with a low reoperation rate of 4.3%.

CONCLUSION

Single-staged posterior MIS effectively corrects global alignment in adult spinal deformities, satisfying patient demand and yielding positive clinical outcome with low re-operation rate.

The ISSG-AO Complication Intervention Score, but Not Major/Minor Designation, is Correlated With Length of Stay Following Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective review.

OBJECTIVES

The International Spine Study Group-AO (ISSG-AO) Adult Spinal Deformity (ASD) Complication Classification System was developed to improve classification, reporting, and study of complications among patients undergoing ASD surgery. The ISSG-AO system classifies interventions to address complications by level of invasiveness: grade zero (none); grade 1, mild (e.g., medication change); grade 2, moderate (e.g., ICU admission); grade 3, severe (e.g., reoperation related to surgery of interest). To evaluate the efficacy of the ISSG-AO ASD Complication Classification System, we aimed to compare correlations between postoperative length of stay (LOS) and complication severity as classified by the ISSG-AO ASD and traditional major/minor complication classification systems.

METHODS

Patients age ≥18 in a multicenter ASD database who sustained in-hospital complications were identified. Complications were classified with the major/minor and ISSG-AO systems and correlated with LOS using an ensemble-based machine learning algorithm (conditional random forest) and a generalized linear mixed model.

RESULTS

490 patients at 19 sites were included. 64.9% of complications were major, and 35.1% were minor. By ISSG-AO classification, 20.4%, 66.1%, 6.7%, and 6.7% were grades 0-3, respectively. ISSG-AO complication grading demonstrated significant correlation with LOS, whereas major/minor complication classification demonstrated inverse correlation with LOS. In conditional random forest analysis, ISSG-AO classification had the greatest relative importance when assessing correlations across multiple variables with LOS.

CONCLUSIONS

The ISSG-AO system may help identify specific complications associated with prolonged LOS. Targeted interventions to avoid or reduce these complications may improve ASD surgical quality and resource utilization.

Long-term results of single-stage posterior hemivertebra resection and short segment fusion using pedicle screws fixation in thoracolumbar congenital early-onset scoliosis: an 8.97-year average follow-up study

BACKGROUND

This study aims to evaluate the long-term outcomes of one-stage posterior hemivertebra resection and short segment fusion with pedicle screw fixation in children with thoracolumbar congenital early-onset scoliosis (TLCEOS). It specifically investigates the durability of spinal correction and the incidence of complications over an average follow-up of 8.97 years.

METHODS

A retrospective review was conducted on 32 patients treated at a tertiary scoliosis referral center from April 2003 to December 2019. Inclusion criteria were thoracolumbar hemivertebra (T11-L1), treatment via posterior hemivertebra resection and short segment fusion (≤ 5 segments), age under 10 years at surgery, and a follow-up of at least 5 years. Exclusions included idiopathic, syndromic, or neuromuscular scoliosis. Data on demographics, surgical procedures, and radiographic outcomes were collected, and clinical outcomes were evaluated using the Scoliosis Research Society-22 (SRS-22) questionnaire. Statistical analysis was performed using SPSS and R software.

RESULTS

The study included 32 patients (22 males, 10 females) with a mean age of 5.00 ± 2.42 years at surgery and an average follow-up of 8.97 ± 2.81 years. On average, 3.47 ± 1.11 segments were fused. The main curve corrected from 38.64° ± 14.12° preoperatively to 9.06° ± 7.29° postoperatively, with a final correction rate of 61%. Significant improvements were observed in the SRS-22 domains of Appearance and Satisfaction with Treatment. There were 17 complications, including neurological, pulmonary, and mechanical issues, with some cases requiring revision surgery.

CONCLUSIONS

One-stage posterior hemivertebra resection and short segment fusion with pedicle screw fixation effectively correct TLCEOS long-term, offering significant improvements in patient appearance and satisfaction, with a manageable complication profile.

Benchmark Values for Construct Survival and Complications by Type of ASD Surgery

OBJECTIVE

The aim of this study was to provide benchmarks for the rates of complications by type of surgery performed.

STUDY DESIGN

Prospective multicenter database.

BACKGROUND

We have previously examined overall construct survival and complication rates for ASD surgery. However, the relationship between type of surgery and construct survival warrants more detailed assessment.

MATERIALS AND METHODS

Eight surgical scenarios were defined based on the levels treated, previous fusion status [primary (P) vs. revision (R)], and three-column osteotomy use (3CO): short lumbar fusion, LT-pelvis with 5 to 12 levels treated (P, R, or 3CO), UT-pelvis with 13 levels treated (P, R, or 3CO), and thoracic to lumbar fusion without pelvic fixation, representing 92.4% of the case in the cohort. Complication rates for each type were calculated and Kaplan-Meier curves with multivariate Cox regression analysis was used to evaluate the effect of the case characteristics on construct survival rate, while controlling for patient profile.

RESULTS

A total of 1073 of 1494 patients eligible for 2-year follow-up (71.8%) were captured. Survival curves for major complications (with or without reoperation), while controlling for demographics differed significantly among surgical types ( P <0.001). Fusion procedures short of the pelvis had the best survival rate, while UT-pelvis with 3CO had the worst survival rate. Longer fusions and more invasive operations were associated with lower 2-year complication-free survival, however, there were no significant associations between type of surgery and renal, cardiac, infection, wound, gastrointestinal, pulmonary, implant malposition, or neurological complications (all P >0.5).

CONCLUSIONS

This study suggests that there is an inherent increased risk of complication for some types of ASD surgery independent of patient profile. The results of this paper can be used to produce a surgery-adjusted benchmark for ASD surgery with regard to complications and survival. Such a tool can have very impactful applications for surgical decision-making and more informed patient counseling.

LEVEL OF EVIDENCE

Level III.

Complications and health-related quality of life following lumbosacral hemivertebra resection and short segmental fusion: a retrospective cohort study

BACKGROUND CONTEXT

Previous literature has provided descriptions of postoperative complications. However, these studies have included heterogeneous cohorts of hemivertebra patients undergoing different surgical methods and addressing deformities at various locations.

PURPOSE

To assess independent risk factors for complications following lumbosacral hemivertebra (LSHV) resection and to further explored the potential association between complications and health-related quality of life (HRQOL).

DESIGN

Retrospective cohort study.

PATIENT SAMPLE

We retrospectively analyzed consecutive patients who underwent LSHV resection and short segment fusion at our institution between 2010 and 2022.

OUTCOME MEASURE

In the current study, the outcome measure were complications and HRQOL.

METHODS

Between 2010 and 2022, a total of 64 consecutive patients with LSHV underwent hemivertebra resection. The diagnostic criteria for LSHV were delineated that the hemivertebra resides caudal to L5 and beyond. Electronic patient record and radiographic data were reviewed retrospectively in our electronic database. According to complications, the patients were divided into with and without complications, and further stratified as neurological, mechanical, and infectious complications. HRQOL outcomes were collected preoperatively, 3 months postoperatively, and at last follow-up using the Scoliosis Research Society-22 (SRS-22) questionnaire. Multivariate logistic regression models were used to determine independent risk factors affecting complications.

RESULTS

A total of 64 patients were enrolled in this study for at least 2-year follow-up. The mean follow-up was 7.3±4.2 years. In the coronal plane, the mean main curve was corrected from 27.3° preoperatively to 8.0° postoperatively, and 9.3° at last follow-up. Global spine balance was significantly improved after surgery, and kept stable during the follow-up. In all, 18 complications were recorded in 15 (23.4%) patients. In the multivariate logistic regression model, 3 independent risk factors for complication were screened out, including age (OR=1.16, 95% CI 1.01-1.34, p=.042), anterior reconstruction (OR=3.40, 95% CI 1.03-11.2, p=.045), and preoperative CB (OR=1.06, 95% CI 1.00-1.12, p=.036). The mean SRS-22 total and domain scores for the entire cohort showed improvement at last follow-up. However, in the noncomplication group, the improvements in SRS-22 scores were more substantial.

CONCLUSION

Postoperative neurological and mechanical complications are common medical events following LSHV resection. The age, anterior column reconstruction, and preoperative coronal balance were the independent risk factors. Compared to the noncomplication group, the improvements in HRQOL are blunted in the complication group.

Complication Rates Following Adult Spinal Deformity Surgery: Evaluation of the Category of Complication and Chronology

OBJECTIVE

Provide benchmarks for the rates of complications by type and timing.

STUDY DESIGN

Prospective multicenter database.

BACKGROUND

Complication rates following adult spinal deformity (ASD) surgery have been previously reported. However, the interplay between timing and complication type warrants further analysis.

METHODS

The data for this study were sourced from a prospective, multicenter ASD database. The date and type of complication were collected and classified into three severity groups (minor, major, and major leading to reoperation). Only complications occurring before the two-year visit were retained for analysis.

RESULTS

Of the 1260 patients eligible for two-year follow-up, 997 (79.1%) achieved two-year follow-up. The overall complication rate was 67.4% (N=672). 247 patients (24.8%) experienced at least one complication on the day of surgery (including intraoperatively), 359 (36.0%) between postoperative day 1 and six weeks postoperatively, 271 (27.2%) between six weeks and one-year postoperatively, and finally 162 (16.3%) between one year and two years postoperatively. Using Kaplan-Meier survival analysis, the rate of remaining complication-free was estimated at different time points for different severities and types of complications. Stratification by type of complication demonstrated that most of the medical complications occurred within the first 60 days. Surgical complications presented over two distinct timeframes. Operative complications, incision-related complications, and infections occurred early (within 60 d), while implant-related and radiographic complications occurred at a constant rate over the two-year follow-up period. Neurological complications had the highest occurrence within the first 60 days but continued to increase up to the two-year visit.

CONCLUSION

Only one-third of ASD patients remained complication-free by two years, and 2 of 10 patients had a complication requiring a reoperation or revision. An estimation of the timing and type of complications associated with surgical treatment may prove useful for more meaningful patient counseling and aid in assessing the cost-effectiveness of treatment.

LEVEL OF EVIDENCE

3.

Evaluation of the usefulness of the Clavien-Dindo classification of surgical complications

The Clavien-Dindo (CD) classification is widely used in the reporting of surgical complications in scientific literature. It groups complications based on the level of intervention required to resolve them, and benefits from simplicity and ease of use, both of which contribute its to high inter-rater reliability. It has been validated for use in many specialties due to strong correlation with key outcome measures including length of stay, postsurgical quality of life and case-related renumeration. Limitations of the classification include concerns over differentiating grade III and IV complications and not classifying intraoperative complications. The Comprehensive Complication Index is an adaptation of the CD classification which generates a morbidity score from 0 to 100. It has been proposed as a more effective method of assessing the morbidity burden of surgical procedures. However, it remains less popular as calculations of morbidity are complicated and time-consuming. In recent years there have been suggestions of adaptations to the CD classification such as the Clavien-Dindo-Sink classification, while in some specialties, completely new classifications have been proposed due to evidence the CD classification is not reliable. Similarly, the Surgical Expertise and Validity Evaluation project aims to determine benchmarks against which surgeons may compare their own practice.

Timing of inpatient medical complications after adult spinal deformity surgery: early ambulation matters

BACKGROUND

The substantial risk for medical complication after adult spinal deformity (ASD) surgery is well known. However, the timing of medical complications during the inpatient stay have not been previously described. Accurate anticipation of complications and adverse events may improve patient counseling and postoperative management.

PURPOSE

(1) Describe the rate of medical complication and adverse events by postoperative day after ASD surgery and (2) determine whether early ambulation is protective for complications.

STUDY DESIGN/SETTING

Single institution retrospective cohort study.

PATIENT SAMPLE

Two hundred thirty-five patients with ASD who underwent posterior-only fusion of the lumbar spine (≥5 levels to the pelvis) between 2013 and 2020.

OUTCOME MEASURES

Medical complications, categorized per the International Spine Study Group-AO system (cardiopulmonary [CP], gastrointestinal [GI], central nervous system [CNS], infectious [nonsurgical site], and renal) and adverse events (postoperative blood transfusion, urinary retention, and electrolyte abnormalities).

METHODS

Patients were identified from an institutional ASD database. Outcome measures were classified by the first postoperative day the event was recognized. Demographics, year of surgery, surgical factors, radiographic parameters, surgical invasiveness (ASD-S Index), frailty (Modified Frailty Index-5 [mFI-5]), Charlson Comorbidity Index (CCI), obstructive sleep apnea (OSA), smoking, preoperative opioid use, depression, and post-operative day of ambulation were assessed as risk factors for inpatient medical complications.

RESULTS

After exclusions of patients with incomplete medical chart data, 191 patients were available for analysis, mean age 66±10 y, BMI 28±5 kg/m2, PI-LL 24±20°, T1PA 28±13°. Inpatient medical complications occurred in 55 (28.8%) patients; adverse events occurred in 137 (71.7%). Length of stay was higher in patients with medical complications (mean 8.5±3.8 vs. 5.8±2.3 days, p<.001). However, for patients who had an adverse event, but no medical complication, LOS was comparable (p>.05). Most medical complications occurred by POD3 (58% of all complications). Risk (defined as the proportion of patients with that complication out of all inpatients that day) of CNS, CP, and GI complication peaked early in the postoperative course (CNS on POD1 [2.1% risk]; GI on POD2 [3.7%]; CP on POD3 [2.7%]). Risk for infectious and renal complications (infectious POD8 [2.7%]; renal POD7 [0.9%]) peaked later (Figure 1). On univariate analysis, patients with medical complications had higher rates of OSA (9.1% vs. 2.2%, p=.045), ASD-S (45.9 vs. 40.8, p=.04), max coronal cobb (46.9 vs. 36.7°, p=.003), ASA class (2.5 vs. 2.3, p=.01), and POD of ambulation (1.9 vs. 1.3, p=.01). On multivariate logistic regression (c-statistic 0.78), larger coronal cobb and later POD of ambulation were independent risk factors for complications (OR 1.04, 95% CI 1.01-1.07 and OR 2.3, 95% CI 1.2-4.7, respectively).

CONCLUSIONS

Our data may inform peri-operative management and patient expectations for hospitalization after ASD surgery. Early ambulation may reduce the risk of complications.

Modified Clavien-Dindo-Sink system is reliable for classifying complications following surgical treatment of early-onset scoliosis

PURPOSE

Appropriately measuring and classifying surgical complications is a critical component of research in vulnerable populations, including children with early-onset scoliosis (EOS). The purpose of this study was to assess the inter- and intra-rater reliability of a modified Clavien-Dindo-Sink system (CDS) classification system for EOS patients among a group of pediatric spinal deformity surgeons.

METHODS

Thirty case scenarios were developed and presented to experienced surgeons in an international spine study group. For each case, surgeons were asked to select a level of severity based on the modified CDS system to assess inter-rater reliability. The survey was administered on two occasions to allow for assessment of intra-rater reliability. Weighted Kappa values were calculated, with 0.61 to 0.80 considered substantial agreement and 0.81 to 1.00 considered nearly perfect agreement.

RESULTS

11/12 (91.7%) surgeons completed the first-round survey and 8/12 (66.7%) completed the second. Inter-observer weighted kappa values for the first and second survey were 0.75 [95% CI 0.56-0.94], indicating substantial agreement, and 0.84 [95% CI 0.70-0.98], indicating nearly perfect agreement, respectively. Intra-observer reliability was 0.86 (range 0.74-0.95) between the first and second surveys, indicating nearly perfect agreement .

CONCLUSION

The modified CDS classification system demonstrated substantial to nearly perfect agreement between and within observers for the evaluation of complications following the surgical treatment of EOS patients. Adoption of this reliable classification system as a standard for reporting complications in EOS patients can be a valuable tool for future research endeavors, as we seek to ultimately improve surgical practices and patient outcomes.

LEVEL OF EVIDENCE

Level V.

Operative treatment outcomes for adult cervical deformity: a prospective multicenter assessment with mean 3-year follow-up

OBJECTIVE

Adult cervical deformity (ACD) has high complication rates due to surgical complexity and patient frailty. Very few studies have focused on longer-term outcomes of operative ACD treatment. The objective of this study was to assess minimum 2-year outcomes and complications of ACD surgery.

METHODS

A multicenter, prospective observational study was performed at 13 centers across the United States to evaluate surgical outcomes for ACD. Demographics, complications, radiographic parameters, and patient-reported outcome measures (PROMs; Neck Disability Index, modified Japanese Orthopaedic Association, EuroQol-5D [EQ-5D], and numeric rating scale [NRS] for neck and back pain) were evaluated, and analyses focused on patients with ≥ 2-year follow-up.

RESULTS

Of 169 patients with ACD who were eligible for the study, 102 (60.4%) had a minimum 2-year follow-up (mean 3.4 years, range 2-8.1 years). The mean age at surgery was 62 years (SD 11 years). Surgical approaches included anterior-only (22.8%), posterior-only (39.6%), and combined (37.6%). PROMs significantly improved from baseline to last follow-up, including Neck Disability Index (from 47.3 to 33.0) and modified Japanese Orthopaedic Association score (from 12.0 to 12.8; for patients with baseline score ≤ 14), neck pain NRS (from 6.8 to 3.8), back pain NRS (from 5.5 to 4.8), EQ-5D score (from 0.74 to 0.78), and EQ-5D visual analog scale score (from 59.5 to 66.6) (all p ≤ 0.04). More than half of the patients (n = 58, 56.9%) had at least one complication, with the most common complications including dysphagia, distal junctional kyphosis, instrumentation failure, and cardiopulmonary events. The patients who did not achieve 2-year follow-up (n = 67) were similar to study patients based on baseline demographics, comorbidities, and PROMs. Over the course of follow-up, 23 of the total 169 enrolled patients were reported to have died. Notably, these represent all-cause mortalities during the course of follow-up.

CONCLUSIONS

This multicenter, prospective analysis demonstrates that operative treatment for ACD provides significant improvement of health-related quality of life at a mean 3.4-year follow-up, despite high complication rates and a high rate of all-cause mortality that is reflective of the overall frailty of this patient population. To the authors' knowledge, this study represents the largest and most comprehensive prospective effort to date designed to assess the intermediate-term outcomes and complications of operative treatment for ACD.

Combined anterior-posterior versus all-posterior approaches for adult spinal deformity correction: a matched control study

PURPOSE

Anterior approaches are gaining popularity for adult spinal deformity (ASD) surgeries especially with the introduction of hyperlordotic cages and improvement in MIS techniques. Combined Approaches provide powerful segmental sagittal correction potential and increase the surface area available for fusion in ASD surgery, both of which would improve overall. This is the first study directly comparing surgical outcomes between combined anterior-posterior approaches and all-posterior approach in a matched ASD population.

METHODS

This is a retrospective matched control cohort analysis with substitution using a multicenter prospectively collected ASD data of patients with > 2 year FU. Matching criteria include: age, American Society of Anesthesiologists Score, Lumbar Cobb angle, sagittal deformity (Global tilt) and ODI.

RESULTS

In total, 1024 ASD patients were available for analysis. 29 Combined Approaches patients met inclusion criteria, and only 22 could be matched (1:2 ratio). Preoperative non-matched demographical, clinical, surgical and radiological parameters were comparable between both groups. Combined approaches had longer surgeries (548 mns vs 283) with more blood loss (2850 ml vs 1471) and needed longer ICU stays (74 h vs 27). Despite added morbidity, they had comparable complication rates but with significantly less readmissions (9.1% vs 38.1%) and reoperations (18.2% vs 43.2%) at 2 years. Combined Approaches achieved more individualised and harmonious deformity correction initially. At the 2 years control, Combined Approaches patients reported better outcomes as measured by COMI and SRS scores. This trend was maintained at 3 years.

CONCLUSION

Despite an increased initial surgical invasiveness, combined approaches seem to achieve more harmonious correction with superior sagittal deformity control; they need fewer revisions and have improved long-term functional outcomes when compared to all-posterior approaches for ASD deformity correction.

Assessment of Adult Spinal Deformity Complication Timing and Impact on 2-Year Outcomes Using a Comprehensive Adult Spinal Deformity Classification System

STUDY DESIGN

Retrospective review of prospectively collected multicenter registry data.

OBJECTIVE

To identify rates and timing of postoperative complications in adult spinal deformity (ASD) patients, the impact of complication type and timing on health related quality of life (HRQoL) outcomes, and the impact of complication timing on readmission and reoperation rates. Better understanding of complication timing and impact on HRQoL may improve patient selection, preoperative counseling, and postoperative complication surveillance.

SUMMARY OF BACKGROUND DATA

ASD is common and associated with significant disability. Surgical correction is often pursued, but is associated with high complication rates. The International Spine Study Group, AO Spinal Deformity Forum, and European Spine Study Group have developed a new complication classification system for ASD (ISSG-AO spine complications classification system).

METHODS

The ISSG-AO spine complications classification system was utilized to assess complications occurring over the 2-year postoperative time period amongst a multicenter, prospectively enrolled cohort of patients who underwent surgery for ASD. Kaplan-Meier survival curves were established for each complication type. Propensity score matching was performed to adjust for baseline disability and comorbidities. Associations between each complication type and HRQoL, and reoperation/readmission and complication timing, were assessed.

RESULTS

Of 584 patients meeting inclusion criteria, cardiopulmonary, gastrointestinal, infection, early adverse events, and operative complications contributed to a rapid initial decrease in complication-free survival. Implant-related, radiographic, and neurologic complications substantially decreased long-term complication-free survival. Only radiographic and implant-related complications were significantly associated with worse 2-year HRQoL outcomes. Need for readmission and/or reoperation was most frequent among those experiencing complications after postoperative day 90.

CONCLUSION

Surgeons should recognize that long-term complications have a substantial negative impact on HRQoL, and should carefully monitor for implant-related and radiographic complications over long-term follow-up.Level of Evidence: 4.

Surgical Factors and Treatment Severity for Perioperative Complications Predict Hospital Length of Stay in Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective review of prospectively collected multicenter registry data.

OBJECTIVE

The aim of this study was to determine whether surgical variables and complications as graded by treatment severity impact postoperative hospital length of stay (LOS).

SUMMARY OF BACKGROUND DATA

Surgical treatment can substantially improve quality of life for patients with adult spinal deformity (ASD). However, surgical treatment is associated with high complication rates, which may impact hospital LOS. Classifying complications by severity of subsequent treatment may allow surgeons to better understand complications and predict their impact on important outcome metrics, including LOS.

METHODS

Patients enrolled in a multicenter, prospectively enrolled database for ASD were assessed for study inclusion. Complications were graded based on intervention severity. Associations between LOS, complication intervention severity, and surgical variables (fusion length, use of interbody fusion, use of major osteotomy, primary versus revision surgery, same day vs. staged surgery, and surgical approach), were assessed. Two multivariate regression models were constructed to assess for independent associations with LOS.

RESULTS

Of 1183 patients meeting inclusion criteria, 708 did not and 475 did experience a perioperative complication during their index hospitalization, with 660 and 436 included in the final cohorts, respectively. Among those with complications, intervention severities included 14.9% with no intervention, 68.6% with minor, 8.9% with moderate, and 7.6% with severe interventions. Multivariate regression modeling demonstrated that length of posterior fusion, use of major osteotomy, staged surgery, and severity of intervention for complications were significantly associated with LOS.

CONCLUSION

Careful selection of surgical factors may help reduce hospital LOS following surgery for ASD. Classification of complications by treatment severity can help surgeons better understand and predict the implications of complications, in turn assisting with surgical planning and patient counseling.Level of Evidence: 4.