Faculty Bibliography

BACKGROUND AND OBJECTIVES/OBJECTIVE:Anterior vertebral body tether (VBT) is a fusionless approach to treat idiopathic scoliosis, and surgeons are beginning to implement the technique into current practice. This study aims to evaluate the learning curve for single and double VBT. METHODS:A retrospective review of 3 surgeons' first 40 single and 20 double VBT was performed. Skeletally immature patients with idiopathic scoliosis who underwent thoracic (single) or thoracolumbar (double) VBT were included. Thoracic VBT was done via video-assisted thoracoscopic surgery and lumbar VBT through a mini-open retroperitoneal approach. Primary outcomes of interest were operative time, radiation exposure, and radiographic correction. Pooled and individual-surgeon analyses were performed. RESULTS:A total of 180 patients were included: 120 single and 60 double. Mean age was 12.7 years, and 87.8% were female. Mean segments tethered was 7.8 in single and 11.0 in double. Mean preoperative thoracic scoliosis was 51.5: single 50.5° and double 53.3°. Mean lumbar scoliosis was 36.4°: single 30.0° and double 49.0°. Average operating time was 276.2 minutes; double VBT was significantly longer (217.3 vs 394.0 minutes, P < .001). Mean blood loss was 198.5 mL, and mean fluoroscopy dose was 73.0 mGy. For single VBT, there was a decrease in operative time (283.3-174.8 minutes, P < .001) and fluoroscopy dose (70.1-53.5 mGy, P = .047) over time. Every 10 cases resulted in a 31.4 minute decrease in operative time (P < .001). There were no intraoperative complications. Single VBT resulted in 54.9% thoracic curve correction. Double VBT achieved 53.0% thoracic and 56.7% lumbar correction. There were no differences in curve correction across the learning curve. CONCLUSION/CONCLUSIONS:VBT is viable fusionless surgical option for scoliosis. As expected, increased experience resulted in shorter operative time; the threshold for such improvement seems to be 10 cases. Importantly, adequate and consistent curve correction can be achieved at the start of the learning curve while mitigating complications.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Pediatric spine surgery has evolved considerably over the past century. No previous study conducted a bibliometric analysis of the corpus of pediatric spine surgery. We used big data and advanced bibliometric analyses to evaluate trends in the progression of pediatric spine surgery as a distinct field since the beginning of the 20th century. METHODS:A Web of Science query was designed to capture the representative corpus of pediatric spine literature. Statistical and bibliometric analyses were performed using various Python packages and the Bibliometrix R package. RESULTS:The collection, published from 1902 to 2023, comprised a total of 11 861 articles from 61 journals and 32 715 unique authors. The overall growth rate annually for publications was 5.08%. An upsurge in publications was seen in the 1980s, after the advent of specialty and subspecialty journals. Illustratively, over 90% of all articles pertaining to pediatric spine surgery were published in the past 3 decades. International and domestic collaboration also increased exponentially over this time period. Reference publication year spectroscopy allowed us to identify 75 articles that comprise the historical roots of modern pediatric spine surgery. There was a recent lexical evolution of topics and terms toward alignment, outcomes, and patient-centric terms. Coauthorship among under-represented groups increased since 1990, but remains low, with disparities persisting across journals. CONCLUSION/CONCLUSIONS:This comprehensive bibliometric analysis on the corpus of pediatric spine surgery offers insight into the evolving landscape of research, authorship, and publication trends over the past century. Advancements in the understanding of the natural history and technology have led the field to become increasingly outcomes focused, all of which have been fueled by pioneering authors. While diversity among authors improves, under-representation of various groups continues to persist, indicating a critical role for further outreach and promotion.

OBJECTIVE:This study aimed to assess whether elderly patients (aged ≥ 70 years) face an elevated risk of complications following pedicle subtraction osteotomy (PSO) for adult spinal deformity (ASD) compared with younger patients (< 70 years) and to evaluate if clinical and radiological outcomes differ between these age groups. METHODS:A retrospective analysis of 513 patients undergoing PSO for ASD by a single surgical team between January 2006 and January 2023 was conducted. Patients were categorized by age (≥ 70 years and < 70 years). Data on clinical, demographic, comorbidity, and radiographic details were collected and compared between the groups. For health-related quality of life assessment, the authors recorded the Oswestry Disability Index (ODI), numeric rating scale (NRS), and Scoliosis Research Society-22 revised (SRS-22r) scores preoperatively and at 6 weeks and 1 year postoperatively. Perioperative complications included major (neurological deficit, death, acute myocardial infarction, stroke), minor (ileus, arrhythmia, delirium), and intraoperative (durotomy, vascular injury). RESULTS:Of 513 patients, 412 were included in the study. Clinical outcomes, as measured by NRS, ODI, and SRS-22r scores, were comparable between groups, with both groups showing significant improvements postoperatively. Radiographic outcomes also showed significant and comparable improvements in sagittal balance and spinopelvic harmony in both groups. Deformity corrections were also well maintained at 1 year postoperatively. The elderly group (mean age 75.48 years) had a higher rate of perioperative complications (44.64%) than the younger group (mean age 59.60 years; 30.33%) (p = 0.0030), primarily minor complications such as delirium and arrhythmia (16.07% vs 8.61%, p = 0.0279). There was no significant difference between groups regarding the major complication rate (elderly group: 20.83% vs younger group: 14.34%, p = 0.1087), intraoperative complication rate (2.98% vs 3.69%, p = 0.6949), short-term complication rate (10.12% vs 8.20%, p = 0.5024), mechanical complication rate (30.95% vs 32.79%, p = 0.6949), and reoperation rate due to mechanical complications (38.46% vs 43.75% p = 0.5470). CONCLUSIONS:Elderly patients undergoing PSO for ASD experience a higher rate of minor complications but can achieve clinical and radiological outcomes that are comparable to those of younger patients. The authors found no significant increase in major, intraoperative, short-term, or mechanical complication rates and their subsequent reoperation rates among the elderly. These findings underscore the effectiveness of PSO in improving the quality of life for patients with ASD across age groups, emphasizing the critical role of personalized perioperative management in enhancing outcomes and minimizing risks for all patients.

BACKGROUND AND OBJECTIVES/OBJECTIVE:Intraoperative red blood cell (RBC) salvage is frequently used in contemporary spine surgery, despite clinical concern in its efficacy as a surrogate for blood-banked allogeneic packed RBCs (pRBCs). During spine surgery, salvaged RBCs (sRBCs) are exposed to injurious high-heat electrocautery, prolonged stasis, and abrasive pharmaceuticals, potentially making sRBCs a poor blood substitute. We therefore sought to scientifically and objectively define the quality of sRBCs in the context of complex spine surgery. METHODS:This is a single-center, prospective, nonrandomized controlled trial of patients undergoing posterior-based multilevel thoracolumbar instrumented fusion for spinal deformity with planned use of intraoperative RBC salvage between June 2022 and July 2023. Surgeries were performed by fellowship-trained spinal neurosurgeons and orthopedic surgeons. The participants were split based on transfusion of sRBCs (given sufficient yield) vs no sRBC transfusion. Primary outcomes were RBC electrolyte composition, indices, deformability, and integrity, which were evaluated in comparison blood samples: Baseline, pRBC, and sRBC. Secondary outcomes were related to clinical effects of sRBC transfusion. Morphological assessment used Stimulated Raman Histology and machine learning. Deformability was assessed using ektacytometry. RESULTS:A total of 174 patients were included. The mean age was 50.2years ±25.4, 58.6% was female, the mean level fused was 10.0 ± 3.9, and 58.0% received sRBCs (median 207.0 mL). sRBCs differed significantly on standard laboratory measures, had a high proportion (30.7%) of shrunken and irregularly spiculated morphologies, and demonstrated abnormal deformability and relaxation kinetics. The hemolysis index was significantly elevated in sRBCs (2.9 ± 1.8) compared with Baseline samples and pRBCs (P < .01). Transfusion of sRBCs was associated with suboptimal resuscitation and provided no practical clinical benefit. CONCLUSION/CONCLUSIONS:RBCs salvaged during posterior thoracolumbar spine surgery are irreversibly injured, with hemolysis index exceeding Food and Drug Administration and Council of Europe transfusion standards in all samples, questioning their efficacy and safety as a blood substitute.

OBJECTIVE:Spinal meningiomas pose unique challenges based on the location of their dural attachment. However, there is a paucity of literature investigating the role of dural attachment location on outcomes after posterior-based approach for spinal meningioma resection. The aim of this study was to investigate any differences in outcomes between dural attachment location subgroups in spinal meningioma patients who underwent posterior-based resection. METHODS:This was a single-institution review of patients who underwent resection of a spinal meningioma from 1997 to 2017. Surgical, oncological, and neurological outcomes were compared between patients with varying dural attachments. Multivariate analysis was utilized. RESULTS:A total of 141 patients were identified. The mean age was 62 years, and 110 women were included. The sites of dural attachments were as follows: 16 (11.3%) dorsal, 31 (22.0%) dorsolateral, 17 (12.1%) lateral, 40 (28.4%) ventral, and 37 (26.2%) ventrolateral. Most meningiomas were WHO grade I (92.2%) and in the thoracic spine (61.0%). All patients underwent a posterior approach for tumor resection. There were no differences between subgroups in terms of largest diameter of tumor resected (p = 0.201), gross-total resection (GTR) or subtotal resection (p = 0.362), Simpson grade of resection, perioperative complications (p = 0.116), long-term neurological deficit (p = 0.100), or postoperative radiation therapy (p = 0.971). Cervical spine location was associated with reduced incidence of GTR (OR 0.271, 95% CI 0.108-0.684, p = 0.006) on multivariate analysis. The overall incidence of recurrence/progression was 4.6%, with no difference (p = 0.800) between subgroups. Similarly, the average length of follow-up was 28.1 months, with no difference between subgroups (p = 0.413). CONCLUSIONS:Posterior-based approaches for resection of spinal meningiomas are safe and effective, regardless of dural attachment location, with similar surgical, oncological, and neurological outcomes. Comparison of long-term recurrence rates between dural attachment subgroups is required.

Over the past generation, outcome measures in spine care have evolved from a reliance on clinician-reported assessment toward recognizing the importance of the patient's perspective and the wide incorporation of patient-reported outcomes (PROs). While patient-reported outcomes are now considered an integral component of outcomes assessments, they cannot wholly capture the state of a patient's functionality. There is a clear need for quantitative and objective patient-centered outcome measures. The pervasiveness of smartphones and wearable devices in modern society, which passively collect data related to health, has ushered in a new era of spine care outcome measurement. The patterns emerging from these data, so-called "digital biomarkers," can accurately describe characteristics of a patient's health, disease, or recovery state. Broadly, the spine care community has thus far concentrated on digital biomarkers related to mobility, although the researcher's toolkit is anticipated to expand in concert with advancements in technology. In this review of the nascent literature, we describe the evolution of spine care outcome measurements, outline how digital biomarkers can supplement current clinician-driven and patient-driven measures, appraise the present and future of the field in the modern era, as well as discuss present limitations and areas for further study, with a focus on smartphones (see Supplemental Digital Content , http://links.lww.com/NEU/D809 , for a similar appraisal of wearable devices).

BACKGROUND:Hirayama disease (HD) is a rare, nonfamilial neuromuscular disease causing cervical myelopathy and deformity, most commonly effecting pubertal Asian males. Patients whose nonoperative treatment fails and who cannot tolerate long-term cervical immobilization, experience relapse after arrest of symptoms, or present with severe features warrant surgical treatment. Here, the authors present an unusual case of HD that resulted in rapid progression of severe cervical kyphosis and discuss surgical management strategies. OBSERVATIONS/METHODS:A 15-year-old male presented with unprovoked neck pain, progressive chin-on-chest phenomenon, and cervical myelopathy. Imaging revealed a severe subaxial cervical kyphosis of 88° and severe spinal cord compression secondary to changes within the thecal sac, ligaments, and bony elements. He underwent a multistage surgery involving halo gravity traction, C3-6 anterior cervical discectomy and fusion, and C2 to T2 posterior instrumented fusion with C3-5 Smith-Petersen osteotomies. Cervical subaxial pedicle screws facilitated deformity correction through a cantilever technique. LESSONS/CONCLUSIONS:HD is rare and often self-limited. For severe or refractory cases of HD, guidelines for surgical management have been suggested, with a variety of approaches deemed efficacious. This is the first case of a patient presenting with such severe cervical deformity; early diagnosis and recognition is the first step toward prompt, adequate management.

STUDY DESIGN/METHODS:Retrospective comparative study. OBJECTIVE:To assess the relationship of fusion mass bone density on computed tomography (CT) and the development of rod fractures (RFs) and proximal junctional kyphosis (PJK). SUMMARY OF BACKGROUND DATA/BACKGROUND:Few studies have evaluated the relationship of fusion mass bone density to mechanical complications. MATERIALS AND METHODS/METHODS:A retrospective review of adult spinal deformity patients who underwent thoracolumbar three-column osteotomy from 2007 to 2017 was performed. All patients underwent routine 1-year CT imaging and had at least 24 months follow-up. Posterior fusion mass bone density was evaluated by measuring hounsfield unit (HU) on CT in three different regions [upper instrumented vertebra (UIV), lower instrumented vertebra, and osteotomy site], and were compared between patients with and without mechanical complications. RESULTS:A total of 165 patients (63.2 years, 33.5% male) were included. Overall PJK rate was 18.8%, and 35.5% of these underwent PJK revision. There was significantly lower density of posterior fusion mass at the UIV in patients who experienced PJK compared with patients without PJK (431.5HU vs. 537.4HU, P =0.026). Overall RF rate was 34.5% and 61.4% of these underwent revision for RFs. Among 57 patients with RFs, 71.9% had pseudarthrosis. Fusion mass density did not differ between patients with or without RFs. However, in RF patients with pseudarthrosis, there was significantly higher bone mass density near the osteotomy compared with those without pseudarthrosis (515.7HU vs. 354.2HU, P =0.012). There were no differences in radiographic sagittal measures between the patients with and without RF or PJK. CONCLUSIONS:Patients with PJK tend to have less dense posterior fusion mass at the UIV. Fusion mass density does not correlate with RF, but greater bone density near the osteotomy was correlated with accompanying pseudarthrosis in patients with RFs. Assessing density of posterior fusion mass on CT may be helpful in assessing risk for PJK and provide insight as to the causes of RFs.

STUDY DESIGN/METHODS:Retrospective review of a prospectively collected multicenter database. OBJECTIVE:To compare outcomes of patients with cerebral palsy (CP) who undergo surgery for scoliosis with normal lordosis (NL) versus hyperlordosis. SUMMARY OF BACKGROUND DATA/BACKGROUND:Surgical correction of scoliosis with lumbar hyperlordosis is challenging. Hyperlordosis may confer higher perioperative morbidity, but this is not well understood. MATERIALS AND METHODS/METHODS:A multicenter database was queried for CP patients who underwent surgery from 2008 to 2017. The minimum follow-up was 2 years. Two groups were identified: lumbar lordosis <75° (NL) versus ≥ 75° hyperlordosis (HL). Perioperative, radiographic, and clinical outcomes were compared. RESULTS:Two hundred seventy-five patients were studied: 236 NL and 39 HL (-75 to -125°). The mean age was 14.1 years, and 52.4% were male. Patients with hyperlordosis had less cognitive impairment (76.9% vs. 94.0%, P =0.008) and higher CPCHILD scores (59.4 vs. 51.0, P =0.003). Other demographics were similar between the groups. Patients with hyperlordosis had greater lumbar lordosis (-90.5 vs. -31.5°, P <0.001) and smaller sagittal vertical axis (-4.0 vs. 2.6 cm, P <0.001). Patients with hyperlordosis had greater estimated blood loss (2222.0 vs. 1460.7 mL, P <0.001) but a similar perioperative complication rate (20.5% vs. 22.5%, P =0.787). Significant correction of all radiographic parameters was achieved in both groups. The HL group had postoperative lumbar lordosis of -68.2° and sagittal vertical axis of -1.0 cm. At a 2-year follow-up, patients with hyperlordosis continued to have higher CPCHILD scores and gained the greatest benefit in overall quality of life measures (20.0 vs. 6.1, P =0.008). The reoperation rate was 10.2%: implant failure (3.6%), pseudarthrosis (0.7%), and wound complications (7.3%). There were no differences in the reoperation rate between the groups. CONCLUSION/CONCLUSIONS:Surgical correction of scoliosis with hyperlordosis is associated with greater estimated blood loss but similar radiographic results, perioperative morbidity, and reoperation rate as normal lordosis. Patients with hyperlordosis gained greater overall health benefits. Correction of ≥25% of hyperlordosis seems satisfactory. LEVEL OF EVIDENCE/METHODS:3.