Segmental Sagittal Alignment in Lumbar Spinal Fusion: A Review of Evidence-Based Evaluation of Preoperative Measurement, Surgical Planning, Intraoperative Execution, and Postoperative Evaluation.

BACKGROUND AND OBJECTIVES: Maintaining and restoring global and regional sagittal alignment is a well-established priority that improves patient outcomes in patients with adult spinal deformity. However, the benefit of restoring segmental (level-by-level) alignment in lumbar fusion for degenerative conditions is not widely agreed on. The purpose of this review was to summarize intraoperative techniques to achieve segmental fixation and the impact of segmental lordosis on patient-reported and surgical outcomes. METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, PubMed, Embase, Cochrane, and Web of Science databases were queried for the literature reporting lumbar alignment for degenerative lumbar spinal pathology. Reports were assessed for data regarding the impact of intraoperative surgical factors on postoperative segmental sagittal alignment and patient-reported outcome measures. Included studies were further categorized into groups related to patient positioning, fusion and fixation, and interbody device (technique, material, angle, and augmentation). RESULTS: A total of 885 studies were screened, of which 43 met inclusion criteria examining segmental rather than regional or global alignment. Of these, 3 examined patient positioning, 8 examined fusion and fixation, 3 examined case parameters, 26 examined or compared different interbody fusion techniques, 5 examined postoperative patient-reported outcomes, and 3 examined the occurrence of adjacent segment disease. The data support a link between segmental alignment and patient positioning, surgical technique, and adjacent segment disease but have insufficient evidence to support a relationship with patient-reported outcomes, cage subsidence, or pseudoarthrosis. CONCLUSION: This review explores segmental correction's impact on short-segment lumbar fusion outcomes, finding the extent of correction to depend on patient positioning and choice of interbody cage. Notably, inadequate restoration of lumbar lordosis is associated with adjacent segment degeneration. Nevertheless, conclusive evidence linking segmental alignment to patient-reported outcomes, cage subsidence, or pseudoarthrosis remains limited, underscoring the need for future research.

Lumbar Disc Replacement Versus Interbody Fusion: Meta-analysis of Complications and Clinical Outcomes.

Background: Lumbar spinal fusion is a commonly performed operation with relatively high complication and revision surgery rates. Lumbar disc replacement is less commonly performed but may have some benefits over spinal fusion. This meta-analysis aims to compare the outcomes of lumbar disc replacement (LDR) versus interbody fusion (IBF), assessing their comparative safety and effectiveness in treating lumbar DDD. Methods: PubMed, Cochrane, and Google Scholar (pages 1-2) were searched up until February 2024. The studied outcomes included operative room (OR) time, estimated blood loss (EBL), length of hospital stay (LOS), complications, reoperations, Oswestry Disability Index (ODI), back pain, and leg pain. Results: Ten studies were included in this meta-analysis, of which six were randomized controlled trials, three were retrospective studies, and one was a prospective study. A total of 1720 patients were included, with 1034 undergoing LDR and 686 undergoing IBF. No statistically significant differences were observed in OR time, EBL, or LOS between the LDR and IBF groups. The analysis also showed no significant differences in the rates of complications, reoperations, and leg pain between the two groups. However, the LDR group demonstrated a statistically significant reduction in mean back pain (p=0.04) compared to the IBF group. Conclusion: Both LDR and IBF procedures offer similar results in managing CLBP, considering OR time, EBL, LOS, complication rates, reoperations, and leg pain, with slight superiority of back pain improvement in LDR. This study supports the use of both procedures in managing degenerative spinal disease.

Laminoplasty Versus Laminectomy and Posterior Fusion for Cervical Myelopathy: A Meta-analysis of Radiographic and Clinical Outcomes.

STUDY DESIGN: Meta-analysis. OBJECTIVE: This meta-analysis investigates the outcomes of laminoplasty (LP) and laminectomy with fusion (LF) to guide effective patient selection for these two procedures. BACKGROUND: While LF traditionally offers the ability for excellent posterior decompression, it may alter cervical spine biomechanics and increase the risk of adjacent segment degeneration. LP aims to preserve the natural kinematics of the spine but has not been universally accepted, and may be associated with inadequate decompression, neck pain, and recurrent stenosis. METHODS: PubMed, Cochrane, and Google Scholar (Pages 1-20) were searched up until March 2024. The outcomes studied were surgery-related outcomes (operating room (OR) time, estimated blood loss (EBL), and length of stay (LOS)), adverse events (overall complications, C5 palsy, and reoperations), radiographic outcomes (cervical lordosis (CL), cervical sagittal vertical axis (cSVA), and T1 slope angle (T1SA)), and patient-reported outcome measures (PROMs) (Neck Disability Index (NDI), Visual Analog Scale (VAS) for neck pain, and Japanese Orthopaedic Association (JOA)). RESULTS: Twenty-two studies were included in this meta-analysis, of which 19 were retrospective studies, two were prospective non-randomized studies, and one was a randomized controlled trial. A total of 2,128 patients were included, with 1,025 undergoing LP and 1,103 undergoing LF. LP patients experienced significantly shorter OR time (P=0.009), less EBL (P=0.02), a lower rate of overall complications (P<0.00001) and C5 palsy (P=0.003), a lower T1SA (P=0.02), and a lower NDI (P=0.0004). No significant difference was observed in the remaining outcomes. CONCLUSION: This meta-analysis demonstrates that for cervical myelopathy, LP has the benefits of shorter OR time, less EBL, and reduced incidence of C5 palsy as well as overall complication rate. Given these findings, LP remains an important surgical option with a favorable complication profile in patients with cervical myelopathy, although careful patient selection is still paramount in choosing the right procedure for individual patients.

Same-Day Versus Staged Spinal Fusion: A Meta-analysis of Clinical Outcomes.

STUDY DESIGN: Meta-Analysis. OBJECTIVE: This meta-analysis aims to compare same-day versus staged spine surgery, assessing their effects on patient care and healthcare system efficiency. BACKGROUND: In spinal surgery, the debate between whether same-day and staged surgeries are better for patients continues, as the decision may impact patient related outcomes, healthcare resources and overall costs. While some surgeons advocate for staged surgeries citing reduced risks of complications, others proclaim same-day surgeries may minimize costs and length of hospital stays. METHODS: PubMed, Cochrane and Google Scholar (Pages 1-20) were searched up until February 2024. The studied outcomes were operative room (OR) time, estimated blood loss (EBL), length of hospital stay (LOS), overall complications, venous thromboembolism (VTE), death, reoperations and non-home discharge. RESULTS: Sixteen retrospective studies were included in this meta-analysis, representing a total of 2346 patients of which 644 underwent staged spinal fusion surgeries and 1702 same-day surgeries. No statistically significant difference was observed in EBL between staged and same-day surgery groups. However, the staged group exhibited a statistically significant longer OR time (P= 0.05) and LOS (P=0.004). A higher rate of overall complications (P=0.002) and VTE (P=0.0008) was significantly associated with the staged group. No significant differences were found in the rates of death, reoperations, and non-home discharge between the two groups. CONCLUSION: Both staged and same-day spinal fusion surgeries showed comparable rates of death, reoperations and non-home discharges for patients undergoing spinal surgeries. However, given the increased OR time, LOS and complications associated with staged spinal surgeries, this study supports same-day surgeries when possible to minimize the burden on healthcare resources and enhance efficiency.

Preoperative Resilience and Improvement in Patient-Reported Outcomes After Lumbar Spinal Fusion.

BACKGROUND: It is incompletely understood how preoperative resilience affects 1-year postoperative outcomes after lumbar spinal fusion. METHODS: Patients undergoing open lumbar spinal fusion at a single-center institution were identified between November 2019 and September 2022. Preoperative resilience was assessed using the Brief Resilience Scale. Demographic data at baseline including age, gender, comorbidities, and body mass index (BMI) were extracted. Patient-reported outcome measures including Oswestry Disability Index, PROMIS (Patient-Reported Outcomes Measurement Information System) Global Physical Health, PROMIS Global Mental Health (GMH), and EuroQol5 scores were collected before the surgery and at 3 months and 1 year postoperatively. Bivariate correlation was conducted between Brief Resilience Scale scores and outcome measures at 3 months and 1 year postoperatively. RESULTS: Ninety-three patients had baseline and 1 year outcome data. Compared with patients with high resilience, patients in the low-resilience group had a higher percentage of females (69.4% vs. 43.9%; P = 0.02), a higher BMI (32.7 vs. 30.1; P = 0.03), and lower preoperative Global Physical Health (35.8 vs. 38.9; P = 0.045), GMH (42.2 vs. 49.2; P < 0.001), and EuroQol scores (0.56 vs. 0.61; P = 0.01). At 3 months postoperatively, resilience was moderately correlated with GMH (r = 0.39) and EuroQol (r = 0.32). Similarly, at 1 year postoperatively, resilience was moderately correlated with GMH (r = 0.33) and EuroQol (r = 0.34). Comparable results were seen in multivariable regression analysis controlling for age, gender, number of levels fused, BMI, Charlson Comorbidity Index, procedure, anxiety/depression, and complications. CONCLUSIONS: Low preoperative resilience can negatively affect patient-reported outcomes 1 year after lumbar spinal fusion. Resiliency is a potentially modifiable risk factor, and surgeons should consider targeted interventions for at-risk patient groups.

Cutibacterium acnes in spine surgery: pathophysiology, diagnosis, and treatment.

Cutibacterium acnes (C. acnes) previously named Propionibacterium acnes (P. acnes) has been increasingly recognized by spine surgeons as a cause of indolent post-surgical spinal infection. Patients infected with C. acnes may present with pseudarthrosis or nonspecific back pain. Currently, microbiological tissue cultures remain the gold standard in diagnosing C. acnes infection. Ongoing research into using genetic sequencing as a diagnostic method shows promising results and may be another future way of diagnosis. Optimized prophylaxis involves the use of targeted antibiotics, longer duration of antibiotic prophylaxis, antibacterial-coated spinal implants, and evidence-based sterile surgical techniques all of which decrease contamination. Antibiotics and implant replacement remain the mainstay of treatment, with longer durations of antibiotics proving to be more efficacious. Local guidelines must consider the surge of antimicrobial resistance worldwide when treating C. acnes.

Impact of Self-Reported Loss of Balance and Gait Disturbance on Outcomes following Adult Spinal Deformity Surgery.

Background: The objective of this study was to evaluate if imbalance influences complication rates, radiological outcomes, and patient-reported outcomes (PROMs) following adult spinal deformity (ASD) surgery. Methods: ASD patients with baseline and 2-year radiographic and PROMs were included. Patients were grouped according to whether they answered yes or no to a recent history of pre-operative loss of balance. The groups were propensity-matched by age, pelvic incidence-lumbar lordosis (PI-LL), and surgical invasiveness score. Results: In total, 212 patients were examined (106 in each group). Patients with gait imbalance had worse baseline PROM measures, including Oswestry disability index (45.2 vs. 36.6), SF-36 mental component score (44 vs. 51.8), and SF-36 physical component score (p < 0.001 for all). After 2 years, patients with gait imbalance had less pelvic tilt correction (-1.2 vs. -3.6°, p = 0.039) for a comparable PI-LL correction (-11.9 vs. -15.1°, p = 0.144). Gait imbalance patients had higher rates of radiographic proximal junctional kyphosis (PJK) (26.4% vs. 14.2%) and implant-related complications (47.2% vs. 34.0%). After controlling for age, baseline sagittal parameters, PI-LL correction, and comorbidities, patients with imbalance had 2.2-times-increased odds of PJK after 2 years. Conclusions: Patients with a self-reported loss of balance/unsteady gait have significantly worse PROMs and higher risk of PJK.

Management of traumatic spinal cord injury: A current concepts review of contemporary and future treatment.

Spinal Cord Injury (SCI) is a condition leading to inflammation, edema, and dysfunction of the spinal cord, most commonly due to trauma, tumor, infection, or vascular disturbance. Symptoms include sensory and motor loss starting at the level of injury; the extent of damage depends on injury severity as detailed in the ASIA score. In the acute setting, maintaining mean arterial pressure (MAP) higher than 85 mmHg for up to 7 days following injury is preferred; although caution must be exercised when using vasopressors such as phenylephrine due to serious side effects such as pulmonary edema and death. Decompression surgery (DS) may theoretically relieve edema and reduce intraspinal pressure, although timing of surgery remains a matter of debate. Methylprednisolone (MP) is currently used due to its ability to reduce inflammation but more recent studies question its clinical benefits, especially with inconsistency in recommending it nationally and internationally. The choice of MP is further complicated by conflicting evidence for optimal timing to initiate treatment, and by the reported observation that higher doses are correlated with increased risk of complications. Thyrotropin-releasing hormone may be beneficial in less severe injuries. Finally, this review discusses many options currently being researched and have shown promising pre-clinical results.

Variability in expenses related to spine oncology care: comparison of payer-negotiated rates at National Cancer Institute-Designated Cancer Centers.

BACKGROUND: As of 2021, the Centers for Medicare and Medicaid Services (CMS) requires all hospitals to publish their commercially negotiated prices. To our knowledge, price variation of spine oncology diagnosis and treatments has not been previously investigated. PURPOSE: The aim of this study is to characterize the availability and variation of prices for spinal oncology services among National Cancer Institute-Designated Cancer Centers (NCI-DCC). STUDY DESIGN: Cross-sectional analysis. METHODS: Cancer centers were identified; those that did not provide patient care or participate in Medicare's Inpatient Prospective System were excluded. A cross-sectional analysis was conducted to gather commercially negotiated prices by searching online for "[center name] price transparency OR machine-readable file OR chargemaster." Data obtained was queried using 44 current procedural terminology (CPT) codes for imaging, procedures, and surgeries relevant to spine oncology. Comparison of prices was achieved by normalizing the median price for each service at each center to the estimated 2022 Medicare reimbursement for the center's Medicare Administrator Contractor. The ratios between the lowest and highest median commercial negotiated price within a center and across all centers were defined as "within-center ratio" and "across-center ratio" respectively. RESULTS: In total, 49 centers disclosed commercial payer-negotiated rates. Mean rate (±SD) for cervical corpectomy was $9,134 (±$10,034), thoracic laminectomy for neoplasm excision was $5,382 (±$5502), superficial bone biopsy was $1,853 (±$1,717), and single-photon emission computerized tomography (SPECT) was $813 (±$232). Within-center ratios ranged from 5.0 (SPECT scan) to 17.8 (radiofrequency bone ablation). Across-center ratios (for codes with > 10 centers reporting) ranged from 9.0 (corpectomy, thoracic, lateral extra-cavitary) to 418.7 (anterior approach cervical corpectomy). CONCLUSIONS: Price transparency for spinal oncology remains elusive despite recent CMS regulatory oversight, with marked heterogeneity in the quality of published rates complicating patients' ability to "shop" for care. Additionally, there continues to be significant variation in commercial rates for spine oncology diagnosis and treatment. CLINICAL SIGNIFICANCE: Despite regulation by CMS, prices for spinal oncology services are not uniformly available to patients and vary between NCI-DCC. The findings of this manuscript present potential barriers for patients to compare and obtain affordable care.

Management of Thoracolumbar Vertebral Fractures and Dislocations in Patients with Ankylosing Conditions of the Spine.

Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are bone-forming spinal conditions which inherently increase spine rigidity and place patients at a higher risk for thoracolumbar fractures. Due to the long lever-arm associated with their pathology, these fractures are frequently unstable and may significantly displace leading to catastrophic neurologic consequences. Operative and non-operative management are considerations in these fractures. However conservative measures including immobilization and bracing are typically reserved for non-displaced or incomplete fractures, or in patients for whom surgery poses a high risk. Thus, first line treatment is often surgery which has historically been an open posterior spinal fusion. Recent techniques such as minimally invasive surgery (MIS) and robotic surgery have shown promising lower complication rates as compared to open techniques, however these methods need to be further validated.

Assessing the Accuracy and Reliability of AI-Generated Responses to Patient Questions Regarding Spine Surgery.

BACKGROUND: In today's digital age, patients increasingly rely on online search engines for medical information. The integration of large language models such as GPT-4 into search engines such as Bing raises concerns over the potential transmission of misinformation when patients search for information online regarding spine surgery. METHODS: SearchResponse.io, a database that archives People Also Ask (PAA) data from Google, was utilized to determine the most popular patient questions regarding 4 specific spine surgery topics: anterior cervical discectomy and fusion, lumbar fusion, laminectomy, and spinal deformity. Bing's responses to these questions, along with the cited sources, were recorded for analysis. Two fellowship-trained spine surgeons assessed the accuracy of the answers on a 6-point scale and the completeness of the answers on a 3-point scale. Inaccurate answers were re-queried 2 weeks later. Cited sources were categorized and evaluated against Journal of the American Medical Association (JAMA) benchmark criteria. Interrater reliability was measured with use of the kappa statistic. A linear regression analysis was utilized to explore the relationship between answer accuracy and the type of source, number of sources, and mean JAMA benchmark score. RESULTS: Bing's responses to 71 PAA questions were analyzed. The average completeness score was 2.03 (standard deviation [SD], 0.36), and the average accuracy score was 4.49 (SD, 1.10). Among the question topics, spinal deformity had the lowest mean completeness score. Re-querying the questions that initially had answers with low accuracy scores resulted in responses with improved accuracy. Among the cited sources, commercial sources were the most prevalent. The JAMA benchmark score across all sources averaged 2.63. Government sources had the highest mean benchmark score (3.30), whereas social media had the lowest (1.75). CONCLUSIONS: Bing's answers were generally accurate and adequately complete, with incorrect responses rectified upon re-querying. The plurality of information was sourced from commercial websites. The type of source, number of sources, and mean JAMA benchmark score were not significantly correlated with answer accuracy. These findings underscore the importance of ongoing evaluation and improvement of large language models to ensure reliable and informative results for patients seeking information regarding spine surgery online amid the integration of these models in the search experience.

Sacroplasty for Sacral Insufficiency Fractures: Narrative Literature Review on Patient Selection, Technical Approaches, and Outcomes.

Sacral insufficiency fractures commonly affect elderly women with osteoporosis and can cause debilitating lower back pain. First line management is often with conservative measures such as early mobilization, multimodal pain management, and osteoporosis management. If non-operative management fails, sacroplasty is a minimally invasive intervention that may be pursued. Candidates for sacroplasty are patients with persistent pain, inability to tolerate immobilization, or patients with low bone mineral density. Before undergoing sacroplasty, patients' bone health should be optimized with pharmacotherapy. Anabolic agents prior to or in conjunction with sacroplasty have been shown to improve patient outcomes. Sacroplasty can be safely performed through a number of techniques: short-axis, long-axis, coaxial, transiliac, interpedicular, and balloon-assisted. The procedure has been demonstrated to rapidly and durably reduce pain and improve mobility, with little risk of complications. This article aims to provide a narrative literature review of sacroplasty including, patient selection and optimization, the various technical approaches, and short and long-term outcomes.

Anterior cervical discectomy and fusion versus cervical disc arthroplasty: an epidemiological review of 433,660 surgical patients from 2011 to 2021.

BACKGROUND CONTEXT: Anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) are commonly performed operations to address cervical radiculopathy and myelopathy. Trends in utilization and revision surgery rates warrant investigation. PURPOSE: To explore the epidemiology, postoperative complications, and reoperation rates of ACDF and CDA DESIGN: Retrospective cohort study. PATIENT SAMPLE: A total of 433,660 patients who underwent ACDF or CDA between 2011 and 2021 were included in this study. OUTCOME MEASURES: The following data were observed for all cases: patient demographics, complications, and revisions. METHODS: The PearlDiver database was queried to identify patients who underwent ACDF and CDA between 2011 and 2021. Epidemiological analyses were performed to examine trends in cervical procedure utilization by age group and year. After matching by age, sex, Charlson Comorbidity Index (CCI), levels of operation, and reason for surgery, the early postoperative (2-week), short-term (2-year), and long-term (5-year) complications of both cervical procedures were examined. RESULTS: In total, 404,195 ACDF and 29,465 CDA patients were included. ACDF utilization rose by 25.25% between 2011 and 2014 while CDA utilization rose by 654.24% between 2011-2019 followed by relative plateauing in both procedures. Mann-Kendall trend test confirmed a significant but small rise in ACDF and large rise in CDA procedures from 2011 to 2021 (p<.001). After matching, ACDF and CDA had an overall complication rate of 12.20% and 8.77%, respectively, with the most common complications being subsequent anterior revision (4.96% and 3.35%) and dysphagia (3.70% and 2.98%). The ACDF cohort, especially multilevel ACDF patients, generally had more complications and higher revision rates than the CDA cohort (p<.05). CONCLUSIONS: While ACDF utilization has plateaued since 2014, CDA rates have risen by a staggering 654.24% over the past decade. ACDF and CDA complication and revision rates were relatively low in comparison to previously published values, with significantly lower rates in CDA. Although a lack of radiographic data in this study limits its power to recommend either procedure for individual patients with cervical radiculopathy or myelopathy, CDA may be associated with minor improvement in the complication and revision profile.

Impact of Hip and Knee Osteoarthritis on Full Body Sagittal Alignment and Compensation for Sagittal Spinal Deformity.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To investigate the effect of lower extremity osteoarthritis on sagittal alignment and compensatory mechanisms in adult spinal deformity (ASD). BACKGROUND: Spine, hip, and knee pathologies often overlap in ASD patients. Limited data exists on how lower extremity osteoarthritis impacts sagittal alignment and compensatory mechanisms in ASD. PATIENTS AND METHODS: In total, 527 preoperative ASD patients with full body radiographs were included. Patients were grouped by Kellgren-Lawrence grade of bilateral hips and knees and stratified by quartile of T1-Pelvic Angle (T1PA) severity into low-, mid-, high-, and severe-T1PA. Full-body alignment and compensation were compared across quartiles. Regression analysis examined the incremental impact of hip and knee osteoarthritis severity on compensation. RESULTS: The mean T1PA for low-, mid-, high-, and severe-T1PA groups was 7.3°, 19.5°, 27.8°, and 41.6°, respectively. Mid-T1PA patients with severe hip osteoarthritis had an increased sagittal vertical axis and global sagittal alignment ( P <0.001). Increasing hip osteoarthritis severity resulted in decreased pelvic tilt ( P =0.001) and sacrofemoral angle ( P <0.001), but increased knee flexion ( P =0.012). Regression analysis revealed that with increasing T1PA, pelvic tilt correlated inversely with hip osteoarthritis and positively with knee osteoarthritis ( r2 =0.812). Hip osteoarthritis decreased compensation through sacrofemoral angle (ß-coefficient=-0.206). Knee and hip osteoarthritis contributed to greater knee flexion (ß-coefficients=0.215, 0.101; respectively). For pelvic shift, only hip osteoarthritis significantly contributed to the model (ß-coefficient=0.100). CONCLUSIONS: For the same magnitude of spinal deformity, increased hip osteoarthritis severity was associated with worse truncal and full body alignment with posterior translation of the pelvis. Patients with severe hip and knee osteoarthritis exhibited decreased hip extension and pelvic tilt but increased knee flexion. This examines sagittal alignment and compensation in ASD patients with hip and knee arthritis and may help delineate whether hip and knee flexion is due to spinal deformity compensation or lower extremity osteoarthritis.

Burst fracture treatment caudal to long posterior spinal fusion for adolescent idiopathic scoliosis utilizing temporary lumbo-pelvic fixation with restoration of lumbar mobility after instrumentation removal.

Background: Thoracolumbar burst fractures are common traumatic spinal fractures. The goals of treatment include stabilization, prevention of neurologic compromise or deformity, and preservation of mobility. The aim of this case report is to describe the occurrence and treatment of an L4 burst fracture caudal to long posterior fusion for adolescent idiopathic scoliosis (AIS). Case report: A 15-year-old girl patient underwent posterior spinal fusion from T3-L3. The patient tolerated the procedure well and there were no complications. Seven years postoperatively, the patient reported to the emergency department with lumbar pain after fall from height. A burst fracture at L4 was diagnosed and temporary posterior instrumentation to the pelvis was performed. One-year postinjury, the hardware was removed with fixation replaced only into the fractured segment. Flexion/extension radiographs revealed restored motion. Conclusions: Treatment of fractures adjacent to fusion constructs may be challenging. This case demonstrates that avoiding fusion may lead to satisfactory outcomes and restoration of mobility after instrumentation removal.

Lumbar Lordosis Redistribution and Segmental Correction in Adult Spinal Deformity (ASD): Does it Matter?

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVE: Evaluate the impact of correcting to normative segmental lordosis values on post-operative outcomes. BACKGROUND: Restoring lumbar lordosis magnitude is crucial in adult spinal deformity surgery, but the optimal location and segmental distribution remains unclear. METHODS: Patients were grouped based on offset to normative segmental lordosis values, extracted from recent publications. Matched patients were within 10% of the cohort's mean offset, less than or over 10% were under- and over-corrected. Surgical technique, PROMs, and surgical complications were compared across groups at baseline and 2-year. RESULTS: 510 patients with an average age of 64.6, mean CCI 2.08, and average follow-up of 25 months. L4-5 was least likely to be matched (19.1%), while L4-S1 was the most likely (24.3%). More patients were overcorrected at proximal levels (T10-L2; Undercorrected, U: 32.2% vs. Matched, M: 21.7% vs. Overcorrected, O: 46.1%) and undercorrected at distal levels (L4-S1: U: 39.0% vs. M: 24.3% vs. O: 36.8%). Postoperative ODI was comparable across correction groups at all spinal levels except at L4-S1 and T10-L2/L4-S1, where overcorrected patients and matched were better than undercorrected (U: 32.1 vs. M: 25.4 vs. O: 26.5, P=0.005; U: 36.2 vs. M: 24.2 vs. O: 26.8, P=0.001; respectively). Patients overcorrected at T10-L2 experienced higher rates of proximal junctional failure (PJF) (U: 16.0% vs. M: 15.6% vs. O: 32.8%, P<0.001) and had greater posterior inclination of the upper instrumented vertebra (UIV) (U: -9.2±9.4° vs. M: -9.6±9.1° vs. O: -12.2±10.0°, P<0.001), whereas undercorrection at these levels led to higher rates of revision for implant failure (U: 14.2% vs. M: 7.3% vs. O: 6.4%, P=0.025). CONCLUSIONS: Patients undergoing fusion for adult spinal deformity suffer higher rates of PJF with overcorrection and increased rates of implant failure with undercorrection based on normative segmental lordosis. LEVEL OF EVIDENCE: IV.

Sagittal Alignment in the Degenerative Lumbar Spine: Surgical Planning.

➤ Sagittal alignment of the spine has gained attention in the field of spinal deformity surgery for decades. However, emerging data support the importance of restoring segmental lumbar lordosis and lumbar spinal shape according to the pelvic morphology when surgically addressing degenerative lumbar pathologies such as degenerative disc disease and spondylolisthesis.➤ The distribution of caudal lordosis (L4-S1) and cranial lordosis (L1-L4) as a percentage of global lordosis varies by pelvic incidence (PI), with cephalad lordosis increasing its contribution to total lordosis as PI increases.➤ Spinal fusion may lead to iatrogenic deformity if performed without attention to lordosis magnitude and location in the lumbar spine.➤ A solid foundation of knowledge with regard to optimal spinal sagittal alignment is beneficial when performing lumbar spinal surgery, and thoughtful planning and execution of lumbar fusions with a focus on alignment may improve patient outcomes.

The Case for Operative Efficiency in Adult Spinal Deformity Surgery: Impact of Operative Time on Complications, Length of Stay, Alignment, Fusion Rates, and Patient-Reported Outcomes.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To analyze the impact of operative room (OR) time in adult spinal deformity (ASD) surgery on patient outcomes. BACKGROUND: It is currently unknown if OR time in ASD patients matched for deformity severity and surgical invasiveness is associated with patient outcomes. MATERIALS AND METHODS: ASD patients with baseline and two-year postoperative radiographic and patient-reported outcome measures (PROM) data, undergoing a posterior-only approach for long fusion (>L1-Ilium) were included. Patients were grouped into short OR time (<40th percentile: <359 min) and long OR time (>60th percentile: >421 min). Groups were matched by age, baseline deformity severity, and surgical invasiveness. Demographics, radiographic, PROM data, fusion rate, and complications were compared between groups at baseline and two years follow-up. RESULTS: In total, 270 patients were included for analysis: the mean OR time was 286 minutes in the short OR group versus 510 minutes in the long OR group ( P <0.001). Age, gender, percent of revision cases, surgical invasiveness, pelvic incidence minus lumbar lordosis, sagittal vertical axis, and pelvic tilt were comparable between groups ( P >0.05). Short OR had a slightly lower body mass index than the short OR group ( P <0.001) and decompression was more prevalent in the long OR time ( P =0.042). Patients in the long group had greater hospital length of stay ( P =0.02); blood loss ( P <0.001); proportion requiring intensive care unit ( P =0.003); higher minor complication rate ( P =0.001); with no significant differences for major complications or revision procedures ( P >0.5). Both groups had comparable radiographic fusion rates ( P =0.152) and achieved improvement in sagittal alignment measures, Oswestry disability index, and Short Form-36 ( P <0.001). CONCLUSION: Shorter OR time for ASD correction is associated with a lower minor complication rate, a lower estimated blood loss, fewer intensive care unit admissions, and a shorter hospital length of stay without sacrificing alignment correction or PROMs. Maximizing operative efficiency by minimizing OR time in ASD surgery has the potential to benefit patients, surgeons, and hospital systems.

Cannabis use Disorder and Complications After Anterior Cervical Diskectomy and Fusion.

OBJECTIVE: The aim of this study, a retrospective database analysis, was to assess the impact of baseline cannabis use disorder (CUD) on perioperative complication outcomes in patients undergoing primary 1- to 2-level anterior cervical diskectomy and fusion (ACDF) surgery. METHODS: The PearlDiver Database was queried from January 2010 to December 2021 for patients who underwent primary 1- to 2-level ACDF surgery for degenerative spine disease. Patients with CUD diagnosis 6 months before the index ACDF surgery (i.e., CUD) were propensity matched with patients without CUD (i.e., control in a ratio of 1:1, employing age, gender, and Charlson Comorbidity Index as matching covariates). Univariate and multivariable analysis models with adjustment of confounding variables were used to evaluate the risk of CUD on perioperative complications between the propensity-matched cohorts. RESULTS: The 1:1 matched cohort included 838 patients in each group. Following multivariate analysis, CUD was demonstrated to be associated with an increased incidence of hospital readmission at 90 days (odds ratio [OR] = 2.64, 95% confidence interval: [1.19 to 6.78], [P = 0.027]) and revision surgery at 1 year postoperative (OR = 3.36, 95% confidence interval: [1.17 to 14.18], [P = 0.049]). CUD was additionally associated with reduced risk of overall medical complications at both 6 months and 1 year postoperative (OR = 0.55, [P = 0.021], and OR = 0.54, [P = 0.015], respectively). CONCLUSIONS: These findings indicate that isolated baseline CUD is associated with an increased risk of hospital readmission at 90 days postoperative and cervical spine reoperation at 1 year after primary 1- to 2-level ACDF surgery with a decrease in overall medical complications, cardiac arrhythmias, and acute renal failure.