Current concepts in adult cervical spine deformity surgery.

Cervical spine deformity surgery has significantly evolved over recent decades. There has been substantial work performed, which has furthered the true understanding of alignment and advancements in surgical technique and instrumentation. Concomitantly, understanding of cervical spine pathology and the contributing drivers have also improved, which have influenced the development of classification systems for cervical spine deformity and the development of treatment-guiding algorithms. This article aims to provide a synopsis of the current knowledge surrounding cervical spine deformity to date, with particular focus on preoperative expected alignment targets, perioperative optimization, and the whole operative strategy.

Assessing the Impact of Radiographic Realignment on Adult Spinal Deformity Patients with Sacroiliac Joint Pain at Presentation.

Background: Adult spinal deformity (ASD) patients with concurrent sacroiliac joint (SIJ) pain are susceptible to worse postoperative outcomes. There is scarce literature on the impact of ASD realignment surgery on SIJ pain. Methods: Patients undergoing ASD realignment surgery were included and stratified by the presence of SIJ pain at the baseline (SIJP+) or SIJ pain absence (SIJP-). Mean comparison tests via ANOVA were used to assess baseline differences between both cohorts. Multivariable regression analyses analyzed factors associated with SIJ pain resolution/persistence, factoring in BMI, frailty, disability, and deformity. Results: A total of 464 patients were included, with 30.8% forming the SIJP+ cohort. At the baseline (BL), SIJP+ had worse disability scores, more severe deformity, higher BMI, higher frailty scores, and an increased magnitude of lower limb compensation. SIJP+ patients had higher mechanical complication (14.7 vs. 8.2%, p = 0.024) and reoperation rates (32.4 vs. 20.2%, p = 0.011) at 2 years. SIJP+ patients who subsequently underwent SI fusion achieved disability score outcomes similar to those of their SIJ- counterparts. Multivariable regression analysis revealed that SIJP+ patients who were aligned in the GAP lordosis distribution index were more likely to report symptom resolution at six weeks (OR 1.56, 95% CI: 1.02-2.37, p = 0.039), 1 year (OR 3.21, 2.49-5.33), and 2 years (OR 3.43, 2.41-7.12). SIJP- patients who did not report symptom resolution by 1 year and 2 years were more likely to demonstrate PI-LL > 5° (OR 1.36, 1.07-2.39, p = 0.045) and SVA > 20 mm (OR 1.62, 1.24-1.71 p = 0.017). Conclusions: SIJ pain in ASD patients may result in worsened pain and disability at presentation. Symptom resolution may be achieved in affected patients by adequate postoperative lumbar lordosis restoration.

Is It Possible for Patients with Early Distal Junctional Kyphosis following Adult Cervical Deformity Corrective Surgery to Achieve Similar Outcomes to Their Unaffected Counterparts? An Analysis of Recovery Kinetics.

Background: Distal junctional kyphosis (DJK) is a concerning complication for surgeons performing cervical deformity (CD) surgery. Patients sustaining such complications may demonstrate worse recovery profiles compared to their unaffected peers. Methods: DJK was defined as a >10° change in kyphosis between LIV and LIV-2, and a >10° index angle. CD patients were grouped according to the development of DJK by 3M vs. no DJK development. Means comparison tests and regression analyses used to analyze differences between groups and arelevant associations. Results: A total of 113 patients were included (17 DJK, 96 non-DJK). DJK patients were more sagittally malaligned preop, and underwent more osteotomies and combined approaches. Postop, DJK patients experienced more dysphagia (17.7% vs. 4.2%; p = 0.034). DJK patients remained more malaligned in cSVA through the 2-year follow-up. DJK patients exhibited worse patient-reported outcomes from 3M to 1Y, but these differences subsided when following patients through to 2Y; they also exhibited worse NDI (65.3 vs. 35.3) and EQ5D (0.68 vs. 0.79) scores at 1Y (both p < 0.05), but these differences had subsided by 2Y. Conclusions: Despite patients exhibiting similar preoperative health-related quality of life metrics, patients who developed early DJK exhibited worse postoperative neck disability following the development of their DJK. These differences subsided by the 2-year follow-up, highlighting the prolonged but eventually successful course of many DJK patients after CD surgery.

Assessing the Economic Benefits of Enhanced Recovery After Surgery (ERAS) Protocols in Adult Cervical Deformity Patients: Is the Initial Additive Cost of Protocols Offset by Clinical Gains?

OBJECTIVE: To assess the financial impact of Enhanced Recovery After Surgery (ERAS) protocols and cost-effectiveness in cervical deformity corrective surgery. STUDY DESIGN: Retrospective review of prospective CD database. BACKGROUND: Enhanced Recovery After Surgery (ERAS) can help accelerate patient recovery and assist hospitals in maximizing the incentives of bundled payment models while maintaining high-quality patient care. However, the economic benefit of ERAS protocols, nor the heterogeneous components that make up such protocols, has not been established. METHODS: Operative CD patients ≥18 y with complete pre-(BL) and up to 2-year(2Y) postop radiographic/HRQL data were stratified by enrollment in Standard-of-Care ERAS beginning in 2020. Differences in demographics, clinical outcomes, radiographic alignment targets, perioperative factors, and complication rates were assessed through means comparison analysis. Costs were calculated using PearlDiver database estimates from Medicare pay scales. QALY was calculated using NDI mapped to SF6D using validated methodology with a 3% discount rate to account for a residual decline in life expectancy. RESULTS: In all, 127 patients were included (59.07±11.16 y, 54% female, 29.08±6.43 kg/m 2 ) in the analysis. Of these patients, 54 (20.0%) received the ERAS protocol. Per cost analysis, ERAS+ patients reported a lower mean total 2Y cost of 35049 USD compared with ERAS- patients at 37553 ( P <0.001). Furthermore, ERAS+ patients demonstrated lower cost of reoperation by 2Y ( P <0.001). Controlling for age, surgical invasiveness, and deformity per BL TS-CL, ERAS+ patients below 70 years old were significantly more likely to achieve a cost-effective outcome by 2Y compared with their ERAS- counterparts (OR: 1.011 [1.001-1.999, P =0.048]. CONCLUSIONS: Patients undergoing ERAS protocols experience improved cost-effectiveness and reduced total cost by 2Y post-operatively. Due to the potential economic benefit of ERAS for patients incorporation of ERAS into practice for eligible patients should be considered.

Assessing the effects of prehabilitation protocols on post-operative outcomes in adult cervical deformity surgery: does early optimization lead to optimal clinical outcomes?

PURPOSE: To investigate the effect of a prehabilitation program on peri- and post-operative outcomes in adult cervical deformity (CD) surgery. METHODS: Operative CD patients ≥ 18 years with complete baseline (BL) and 2-year (2Y) data were stratified by enrollment in a prehabilitation program beginning in 2019. Patients were stratified as having undergone prehabilitation (Prehab+) or not (Prehab-). Differences in pre and post-op factors were assessed via means comparison analysis. Costs were calculated using PearlDiver database estimates from Medicare pay-scales. RESULTS: 115 patients were included (age: 61 years, 70% female, BMI: 28 kg/m2). Of these patients, 57 (49%) were classified as Prehab+. At baseline, groups were comparable in age, gender, BMI, CCI, and frailty. Surgically, Prehab+ were able to undergo longer procedures (p = 0.017) with equivalent EBL (p = 0.627), and shorter SICU stay (p < 0.001). Post-operatively, Prehab+ patients reported greater reduction in pain scores and greater improvement in quality of life metrics at both 1Y and 2Y than Prehab- patients (all p < 0.05). Prehab+ patients reported significantly less complications overall, as well as less need for reoperation (all p < 0.05). CONCLUSION: Introducing prehabilitation protocols in adult cervical deformity surgery may aid in improving patient physiological status, enabling patients to undergo longer surgeries with lessened risk of peri- and post-operative complications.

Impact of congestive heart failure on patients undergoing lumbar spine fusion for adult spine deformity.

Background: With the increasing amount of elective spine fusion patients presenting with cardiac disease and congestive heart failure, it is becoming difficult to assess when it is safe to proceed with surgery. Assessing the severity of heart failure (HF) through ejection fraction may provide insight into patients' short- and long-term risks. Purpose: The purpose of this study was to assess the severity of HF on perioperative outcomes of spine fusion surgery patients. Study Design/Setting: This was a retrospective cohort study of the PearlDiver database. Patient Sample: We enrolled 670,526 patients undergoing spine fusion surgery. Outcome Measures: Thirty-day and 90-day complication rates, discharge destination, length of stay (LOS), physician reimbursement, and hospital costs. Methods: Patients undergoing elective spine fusion surgery were isolated and stratified by preoperative HF with preserved ejection fraction (P-EF) or reduced ejection fraction (R-EF) (International Classification of Diseases-9: 428.32 [chronic diastolic HF] and 428.22 [chronic systolic HF]). Means comparison tests (Chi-squared and independent samples t-tests, as appropriate) compared differences in demographics, diagnoses, comorbidities, procedural characteristics, LOS, 30-day and 90-day complication outcomes, and total hospital charges between those diagnosed with P-EF and those not R-EF. Binary logistic regression assessed the odds of complication associated with HF, controlling for levels fused (odds ratio [OR] [95% confidence interval]). Statistical significance was set at P < 0.05. Results: Totally 670,526 elective spine fusion patients were included. Four thousand and seventy-seven were diagnosed with P-EF and 2758 R-EF. Overall, P-EF patients presented with higher rates of morbid obesity, chronic kidney disease, chronic obstructive pulmonary disease, diabetes mellitus, and hypertension (all P < 0.001). In relation to No-HF, P-EF patients had higher rates of 30-day major complications including pulmonary embolism, pneumonia, cerebrovascular accident (CVA), myocardial infarctions (MI), sepsis, and death (all P < 0.001). Furthermore, P-EF was associated significantly with increased odds of pneumonia (OR: 2.07 [1.64-2.56], P < 0.001) and sepsis (OR: 2.09 [1.62-2.66], P < 0.001). Relative to No-HF, R-EF was associated with significantly higher odds of MI (OR: 3.66 [2.34-5.47]), CVA (OR: 2.70 [1.67-4.15]), and pneumonia (OR: 1.85 [1.40-2.40]) (all P < 0.001) postoperative within 30 days. Adjusting for prior history of MI, CAD, and the presence of a pacemaker R-EF was a significant predictor of an MI 30 days postoperatively (OR: 2.2 [1.14-4.32], P = 0.021). Further adjusting for history of CABG or stent placement, R-EF was associated with higher odds of CVA (OR: 2.11 [1.09-4.19], P = 0.028) and MI (OR: 2.27 [1.20-4.43], P = 0.013). Conclusions: When evaluating the severity of HF before spine surgery, R-EF was associated with a higher risk of major complications, especially the occurrence of a myocardial infarction 30 days postoperatively. During preoperative risk assessment, congestive HF should be considered thoroughly when thinking of postoperative outcomes with emphasis on R-EF.

Highest Achievable Outcomes for Adult Spinal Deformity Corrective Surgery: Does Frailty Severity Exert a Ceiling Effect?

STUDY DESIGN: Retrospective Single-Center Study. OBJECTIVE: To assess the influence of frailty on optimal outcome following ASD corrective surgery. SUMMARY OF BACKGROUND DATA: Frailty is a determining factor in outcomes after ASD surgery and may exert a ceiling effect on best possible outcome. METHODS: ASD patients with frailty measures, baseline and 2-year ODI included. Frailty was classified as Not Frail (NF), Frail (F) and Severely Frail (SF) based on the modified Frailty Index, then stratified into quartiles based on 2-year ODI improvement (most improved designated "Highest"). Logistic regression analyzed relationships between frailty and ODI score and improvement, maintenance, or deterioration. A Kaplan-Meier survival curve was used to analyze differences in time to complication or reoperation. RESULTS: 393 ASD patients were isolated (55.2% NF, 31.0% F, and 13.7% SF), then classified as 12.5% NF-Highest, 17.8% F-Highest, and 3.1% SF-Highest. The SF-group had the highest rate of deterioration (16.7%, P=0.025) at the second postoperative year but the groups were similar in improvement (NF: 10.1%, F: 11.5%, SF: 9.3%, P=0.886). Improvement of SF patients was greatest at 6 months (ΔODI of -22.6±18.0, P<0.001) but NF and F patients reached maximal ODI at 2 years (ΔODI of -15.7±17.9 and -20.5±18.4, respectively). SF patients initially showed the greatest improvement in ODI (NF: -4.8±19.0, F: -12.4±19.3, SF: -22.6±18.0 at 6 months, P<0.001). A Kaplan-Meier survival curve showed a trend of less time to major complication or reoperation by 2 years with increasing frailty (NF: 7.5±0.381 years, F: 6.7±0.511 years, SF: 5.8±0.757 years; P=0.113). CONCLUSIONS: Increasing frailty had a negative effect on maximal improvement, where severely frail patients exhibited a parabolic effect with greater initial improvement due to higher baseline disability, but reached a ceiling effect with less overall maximal improvement. Severe frailty may exert a ceiling effect on improvement and impair maintenance of improvement following surgery. LEVEL OF EVIDENCE: III.

The Impact of Peri-operative Enhanced Recovery After Surgery Protocols on Outcomes Following Adult Cervical Deformity Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To assess the impact of Enhanced recovery after surgery (ERAS) protocols on peri-operative course in adult cervical deformity (ACD) corrective surgery. METHODS: Patients ≥18 yrs with complete pre-(BL) and up to 2-year (2Y) radiographic and clinical outcome data were stratified by enrollment in an ERAS protocol that commenced in 2020. Differences in demographics, clinical outcomes, radiographic alignment targets, peri-operative factors and complication rates were assessed via means comparison analysis. Logistic regression analysed differences while controlling for baseline disability and deformity. RESULTS: We included 220 patients (average age 58.1 ± 11.9 years, 48% female). 20% were treated using the ERAS protocol (ERAS+). Disability was similar between both groups at baseline. When controlling for baseline disability and myelopathy, ERAS- patients were more likely to utilize opioids than ERAS+ (OR 1.79, 95% CI: 1.45-2.50, P = .016). Peri-operatively, ERAS+ had significantly lower operative time (P < .021), lower EBL (583.48 vs 246.51, P < .001), and required significantly lower doses of propofol intra-operatively than ERAS- patients (P = .020). ERAS+ patients also reported lower mean LOS overall (4.33 vs 5.84, P = .393), and were more likely to be discharged directly to home (χ2(1) = 4.974, P = .028). ERAS+ patients were less likely to require steroids after surgery (P = .045), were less likely to develop neuromuscular complications overall (P = .025), and less likely experience venous complications or be diagnosed with venous disease post-operatively (P = .025). CONCLUSIONS: Enhanced recovery after surgery programs in ACD surgery demonstrate significant benefit in terms of peri-operative outcomes for patients.

Risk of spinal surgery among individuals who have been re-vascularized for coronary artery disease.

HYPOTHESIS: Revascularization is a more effective intervention to reduce future postop complications. METHODS: Patients undergoing elective spine fusion surgery were isolated in the PearlDiver database. Patients were stratified by having previous history of vascular stenting (Stent), coronary artery bypass graft (CABG), and no previous heart procedure (No-HP). Means comparison tests (chi-squared and independent samples t-tests, as appropriate) compared differences in demographics, diagnoses, and comorbidities. Binary logistic regression assessed the odds of 30-day and 90-day postoperative (postop) complications associated with each heart procedure (Odds Ratio [95 % confidence interval]). Statistical significance was set p < 0.05. RESULTS: 731,173 elective spine fusion patients included. Overall, 8,401 pts underwent a CABG, 24,037 pts Stent, and 698,735 had No-HP prior to spine fusion surgery. Compared to Stent and No-HP patients, CABG patients had higher rates of morbid obesity, chronic kidney disease, and diabetes (p < 0.001 for all). Meanwhile, stent patients had higher rates of PVD, hypertension, and hyperlipidemia (all p < 0.001). 30-days post-op, CABG patients had significantly higher complication rates including pneumonia, CVA, MI, sepsis, and death compared to No-HP (all p < 0.001). Stent patients vs. No-HF had higher 30-day post-op complication rates including pneumonia, CVA, MI, sepsis, and death. Furthermore, adjusting for age, comorbidities, and sex Stent was significantly predictive of a MI 30-days post-op (OR: 1.90 [1.53-2.34], P < 0.001). Additionally, controlling for levels fused, stent patients compared to CABG patients had 1.99x greater odds of a MI within 30-days (OR: 1.99 [1.26-3.31], p = 0.005) and 2.02x odds within 90-days postop (OR: 2.2 [1.53-2.71, p < 0.001). CONCLUSION: With regards to spine surgery, coronary artery bypass graft remains the gold standard for risk reduction. Stenting does not appear to minimize risk of experiencing a post-procedure cardiac event as dramatically as CABG.

The Evolution of Enhanced Recovery After Surgery: Assessing the Clinical Benefits of Developments Within Enhanced Recovery After Surgery Protocols in Adult Cervical Deformity Surgery.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To investigate the impact of evolving Enhanced Recovery After Surgery (ERAS) protocols on outcomes after cervical deformity (CD) surgery. BACKGROUND: ERAS can help accelerate patient recovery and assist hospitals in maximizing the incentives of bundled payment models while maintaining high-quality patient care. However, there remains a paucity of literature assessing how developments have impacted outcomes after adult CD surgery. METHODS: Patients with operative CD 18 years or older with pre-baseline and 2 years (2Y) postoperative data, who underwent ERAS protocols, were stratified by increasing implantation of ERAS components: (1) early (multimodal pain program), (2) intermediate (early protocol + paraspinal blocks, early ambulation), and (3) late (early/intermediate protocols + comprehensive prehabilitation). Differences in demographics, clinical outcomes, radiographic alignment targets, perioperative factors, and complication rates were assessed through Bonferroni-adjusted means comparison analysis. RESULTS: A total of 131 patients were included (59.4 ± 11.7 y, 45% females, 28.8 ± 6.0 kg/m 2 ). Of these patients, 38.9% were considered "early," 36.6% were "intermediate," and 24.4% were "late." Perioperatively, rates of intraoperative complications were lower in the late group ( P = 0.036). Postoperatively, discharge disposition differed significantly between cohorts, with late patients more likely to be discharged to home versus early or intermediate cohorts [χ 2 (2) = 37.973, P < 0.001]. In terms of postoperative disability recovery, intermediate and late patients demonstrated incrementally improved 6 W modified Japanese Orthopedic Association scores ( P = 0.004), and late patients maintained significantly higher mean Euro-QOL 5-Dimension Questionnaire and modified Japanese Orthopedic Association scores by 1 year ( P < 0.001, P = 0.026). By 2Y, cohorts demonstrated incrementally increasing SWAL-QOL scores (all domains P < 0.028) domain scores versus early or intermediate cohorts. By 2Y, incrementally decreasing reoperation was observed in early versus intermediate versus late cohorts ( P = 0.034). CONCLUSIONS: The present study demonstrates that patients enrolled in an evolving ERAS program demonstrate incremental improvement in preoperative optimization and candidate selection, greater likelihood of discharge to home, decreased postoperative disability and dysphasia burden, and decreased likelihood of intraoperative complications and reoperation rates.

Developing a risk score to inform the use of rhBMP-2 in adult spinal deformity surgery.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) has not shown superior benefit overall in cost-effectiveness during adult spinal deformity (ASD) surgery. STUDY DESIGN/SETTING: Retrospective PURPOSE: Generate a risk score for pseudarthrosis to inform the utilization of rhBMP-2, balancing costs against quality of life and complications. METHODS: ASD patients with 3-year data were included. Quality of life gained was calculated from ODI to SF-6D and translated to quality-adjusted life years (QALYs). Cost was calculated using the PearlDiver database and CMS definitions for complications and comorbidities. Established weights were generated for predictive variables via logistic regression to yield a predictive risk score for pseudarthrosis that accounted for frailty, diabetes, depression, ASA grade, thoracolumbar kyphosis and three-column osteotomy use. Risk score categories, established via conditional inference tree (CIT)-derived thresholds were tested for cost-utility of rhBMP-2 usage, controlling for age, prior fusion, and baseline deformity and disability. RESULTS: 64% of ASD patients received rhBMP-2 (308/481). There were 17 (3.5%) patients that developed pseudarthrosis. rhBMP-2 use overall did not lower pseudarthrosis rates (OR: 0.5, [0.2-1.3]). Pseudarthrosis rates for each risk category were: No Risk (NoR) 0%; Low-Risk (LowR) 1.6%; Moderate Risk (ModR) 9.3%; High-Risk (HighR) 24.3%. Patients receiving rhBMP-2 had similar QALYs overall to those that did not (0.163 vs. 0.171, p = .65). rhBMP-2 usage had worse cost-utility in the LowR cohort (p < .001). In ModR patients, rhBMP-2 usage had equivocal cost-utility ($53,398 vs. $61,581, p = .232). In the HighR cohort, the cost-utility was reduced via rhBMP-2 usage ($98,328 vs. $211,091, p < .001). CONCLUSION: Our study shows rhBMP-2 demonstrates effective cost-utility for individuals at high risk for developing pseudarthrosis. The generated score can aid spine surgeons in the assessment of risk and enhance justification for the strategic use of rhBMP-2 in the appropriate clinical contexts. LEVEL OF EVIDENCE: III.

Expectations of clinical improvement following corrective surgery for adult cervical deformity based on functional disability at presentation.

PURPOSE: To assess impact of baseline disability on HRQL outcomes. METHODS: CD patients with baseline (BL) and 2 year (2Y) data included, and ranked into quartiles by baseline NDI, from lowest/best score (Q1) to highest/worst score (Q4). Means comparison tests analyzed differences between quartiles. ANCOVA and logistic regressions assessed differences in outcomes while accounting for covariates (BL deformity, comorbidities, HRQLs, surgical details and complications). RESULTS: One hundred and sixteen patients met inclusion (Age:60.97 ± 10.45 years, BMI: 28.73 ± 7.59 kg/m2, CCI: 0.94 ± 1.31). The cohort mean cSVA was 38.54 ± 19.43 mm and TS-CL: 37.34 ± 19.73. Mean BL NDI by quartile was: Q1: 25.04 ± 8.19, Q2: 41.61 ± 2.77, Q3: 53.31 ± 4.32, and Q4: 69.52 ± 8.35. Q2 demonstrated greatest improvement in NRS Neck at 2Y (-3.93), compared to Q3 (-1.61, p = .032) and Q4 (-1.41, p = .015). Q2 demonstrated greater improvement in NRS Back (-1.71), compared to Q4 (+ 0.84, p = .010). Q2 met MCID in NRS Neck at the highest rates (69.9%), especially compared to Q4 (30.3%), p = .039. Q2 had the greatest improvement in EQ-5D (+ 0.082), compared to Q1 (+ 0.073), Q3 (+ 0.022), and Q4 (+ 0.014), p = .034. Q2 also had the greatest mJOA improvement (+ 1.517), p = .042. CONCLUSIONS: Patients in Q2, with mean BL NDI of 42, consistently demonstrated the greatest improvement in HRQLs whereas those in Q4, (NDI 70), saw the least. BL NDI between 39 and 44 may represent a disability "Sweet Spot," within which operative intervention maximizes patient-reported outcomes. Furthermore, delaying intervention until patients are severely disabled, beyond an NDI of 61, may limit the benefits of surgery.

Predictors of reoperation for spinal disorders in Chiari malformation patients with prior surgical decompression.

Background: Chiari malformation (CM) is a cluster of related developmental anomalies of the posterior fossa ranging from asymptomatic to fatal. Cranial and spinal decompression can help alleviate symptoms of increased cerebrospinal fluid pressure and correct spinal deformity. As surgical intervention for CM increases in frequency, understanding predictors of reoperation may help optimize neurosurgical planning. Materials and Methods: This was a retrospective analysis of the prospectively collected Healthcare Cost and Utilization Project's California State Inpatient Database years 2004-2011. Chiari malformation Types 1-4 (queried with ICD-9 CM codes) with associated spinal pathologies undergoing stand-alone spinal decompression (queried with ICD-9 CM procedure codes) were included. Cranial decompressions were excluded. Results: One thousand four hundred and forty-six patients (29.28 years, 55.6% of females) were included. Fifty-eight patients (4.01%) required reoperation (67 reoperations). Patients aged 40-50 years had the most reoperations (11); however, patients aged 15-20 years had a significantly higher reoperation rate than all other groups (15.5% vs. 8.2%, P = 0.048). Female gender was significantly associated with reoperation (67.2% vs. 55.6%, P = 0.006). Medical comorbidities associated with reoperation included chronic lung disease (19% vs. 6.9%, P < 0.001), iron deficiency anemia (10.3% vs. 4.1%, P = 0.024), and renal failure (3.4% vs. 0.9%, P = 0.05). Associated significant cluster anomalies included spina bifida (48.3% vs. 34.8%, P = 0.035), tethered cord syndrome (6.9% vs. 2.1%, P = 0.015), syringomyelia (12.1% vs. 5.9%, P = 0.054), hydrocephalus (37.9% vs. 17.7%, P < 0.001), scoliosis (13.8% vs. 6.4%, P = 0.028), and ventricular septal defect (6.9% vs. 2.3%, P = 0.026). Conclusions: Multiple medical and CM-specific comorbidities were associated with reoperation. Addressing them, where possible, may aid in improving CM surgery outcomes.