Spine

Spine

“Naples. Awakening in the December Morning.”

01-12-2019 –

Journal Article

No abstract available

Mesenchymal Stem Cell Homing Into Intervertebral Discs Enhances the Tie2-positive Progenitor Cell Population, Prevents Cell Death, and Induces a Proliferative Response

01-12-2019 – Wangler, Sebastian; Peroglio, Marianna; Menzel, Ursula; Benneker, Lorin M.; Haglund, Lisbet; Sakai, Daisuke; Alini, Mauro; Grad, Sibylle

Study Design. Experimental study with human mesenchymal stem cells (MSCs) and intervertebral disc (IVD) tissue samples.
Objective. This study aimed to characterize the effect of MSC homing on the Tie2-positive IVD progenitor cell population, IVD cell survival, and proliferation.
Summary of Background Data. Homing of human MSCs has been described as potential alternative to MSC injection, aiming to enhance the regenerative capacity of the IVD. IVD cells expressing Tie2 (also known as CD202b or Angiopoietin-1 receptor TEK tyrosine kinase) represent a progenitor cell population with discogenic differentiation potential. However, the fraction of Tie2-positive progenitor cells decreases with aging and degree of IVD degeneration, resulting in a potential loss of the IVDs regenerative capacity.
Methods. Human MSCs, isolated from vertebral bone marrow aspirates, were labeled and seeded onto the endplate of bovine IVDs and human IVD tissue. Following MSC migration for 5 days, IVD cells were isolated by tissue digestion. The fractions of Tie2-positive, dead, apoptotic, and proliferative IVD cells were evaluated by flow cytometry and compared to untreated IVDs. For human IVDs, 3 groups were investigated: nondegenerated (organ donors), IVDs of patients suffering from spinal trauma, and degenerative IVD tissue samples.
Results. MSC homing enhanced the fraction of Tie2-positive IVD cells in bovine and human IVD samples. Furthermore, a proliferative response and lower fraction of dead cells were observed after MSC homing in both bovine and human IVD tissues.
Conclusion. Our findings indicate that MSC homing enhances the survival and regenerative capability of IVD cells, which may be mediated by intercellular communication. MSC homing could represent a potential treatment strategy to prevent the onset of the degenerative cascade in IVDs at risk such as IVDs adjacent to a fused segment or IVDs after herniation.
Level of Evidence: N/A

Association of Susceptibility Genes for Adolescent Idiopathic Scoliosis and Intervertebral Disc Degeneration With Adult Spinal Deformity

01-12-2019 – Takeda, Kazuki; Kou, Ikuyo; Hosogane, Naobumi; Otomo, Nao; Yagi, Mitsuru; Kaneko, Shinjiro; Kono, Hitoshi; Ishikawa, Masayuki; Takahashi, Yohei; Ikegami, Takeshi; Nojiri, Kenya; Okada, Eijiro; Funao, Haruki; Okuyama, Kunimasa; Tsuji, Takashi; Fujita, Nobuyuki; Nagoshi, Narihito; Tsuji, Osahiko; Ogura, Yoji; Ishii, Ken; Nakamura, Masaya; Matsumoto, Morio; Ikegawa, Shiro; Watanabe, Kota

Journal Article

Study Design. Genetic case-control study of single nucleotide polymorphisms (SNPs).
Objective. To examine the association of previously reported susceptibility genes for adolescent idiopathic scoliosis (AIS) and intervertebral disc (IVD) degeneration with adult spinal deformity (ASD).
Summary of Background Data. ASD is a spinal deformity that develops and progresses with age. Its etiology is unclear. Several ASD susceptibility genes were recently reported using a candidate gene approach; however, the sample sizes were small and associations with ASD development were not determined.
Methods. ASD was defined as structural scoliosis with a Cobb angle more than 15° on standing radiographs, taken of patients at age 40 to 75 years in this study. Subjects in whom scoliosis was diagnosed before age 20 were excluded. We recruited 356 Japanese ASD subjects and 3341 healthy controls for case-control association studies of previously reported SNPs. We genotyped four known AIS-associated SNPs (rs11190870 in LBX1, rs6570507 in GPR126, rs10738445 in BNC2, and rs6137473 in PAX1) and three IVD degeneration-associated SNPs (rs1245582 in CHST3, rs2073711 in CILP, and rs1676486 in COL11A1) by the Invader assay.
Results. Among the AIS-associated SNPs, rs11190870 and rs6137473 showed strong and nominal associations with ASD (P = 1.44 × 10−4, 1.00 × 10−2, respectively). Of the IVD degeneration-associated SNPs, rs1245582 and rs2073711 showed no association with ASD, while rs1676486 showed a nominal association (P = 1.10 × 10−2). In a subgroup analysis, rs11190870 was significantly associated with a Cobb angle more than 20° in the minor thoracic curve (P = 1.44 × 10−4) and with a left convex lumbar curve (P = 6.70 × 10−4), and nominally associated with an apical vertebra higher than L1 (P = 1.80 × 10−2).
Conclusion. rs11190870 in LBX1, a strong susceptibility SNP for AIS, may also be a susceptibility SNP for ASD. Thus, ASD and AIS may share a common genetic background.
Level of Evidence: 4

Treg-promoted New Bone Formation Through Suppressing Th17 by Secreting Interleukin-10 in Ankylosing Spondylitis

01-12-2019 – Xu, Fan; Guanghao, Chi; Liang, Yan; Jun, Wang; Wei, Wu; Baorong, He

Journal Article

Study Design. Retrospective single-center study.
Objective. We want to know whether interleukin (IL)-10-secreting regulatory T cells (Treg) promote the new bone formation (NBF) through suppressing Th17 in ankylosing spondylitis (AS).
Summary of Background Data. NBF in AS is unknown. Since there are balances of bone remodeling in human body and proinflammatory helper T cells Th17 promoted bone resorption.
Methods. Eighteen AS patients with or without NBF (both nine cases) and nine healthy individuals were selected and the demographic data, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), MRI sacroiliitis score (MRISIS), and computer tomography sacroiliitis score (CTSIS) were recorded. Removed hip ligament tissue in the lesions after arthroplasty was collected and the lymphocytes and the peripheral blood mononuclear cells were prepared. Second, pathological section in hematoxylin–eosin stain were analyzed and flow cytometry and quantitative polymerase chain reaction analyses were carried out to detect the levels of Th17, Treg, IL-10, and nuclear factor (NF)-κB, and the relevance between them. The effect of Treg on Th17 was further analyzed by using Transwell coculturing.
Results. Compared to AS patients without NBF, AS patients with NBF had significantly higher CTSIS and complications (P < 0.05 and 0.01, respectively), but significantly lower BASDAI (3.0 ± 0.4) and MRISIS (3.3 ± 0.8) (P < 0.01 and 0.05, respectively) and no acute inflammation in HE stain for hip joint. Compared to healthy donors, the ratio of Th17/Treg was significantly higher in AS patients without NBF and lower in AS patient with NBF (both P < 0.01) in flow cytometry analysis (FCA). Furthermore, Th17 significantly decreased after indirectly coculturing with Treg in FCA (P < 0.01). Finally, IL-10 had significantly higher m
RNA expression in AS patients with NBF (P < 0.01), and NF-κB had significantly higher m
RNA expression in AS patients without NBF (P < 0.05) than healthy donors. Only the m
RNA expression of IL-10 was significantly correlated to the ratio of Th17/Treg (r = −0.93, P < 0.01).
Conclusion. Treg-induced NBF of AS through suppressing Th17 by secreting IL10 and declining of the ratio of Th17/Treg indicated the development of NBF. This is important not only for screening development of NBF, but also for control of NBF of AS by immune therapy.
Level of Evidence: N/A

Procalcitonin and Neutrophil Lymphocyte Ratio After Spinal Instrumentation Surgery

01-12-2019 – Inose, Hiroyuki; Kobayashi, Yutaka; Yuasa, Masato; Hirai, Takashi; Yoshii, Toshitaka; Okawa, Atsushi

Journal Article

Study Design. This was a retrospective observational study.
Objective. To assess the diagnostic value of procalcitonin (PCT) and neutrophil lymphocyte ratio (NLR) for predicting surgical site infection (SSI) in patients undergoing spinal instrumentation surgery, we analyzed a large consecutive cohort of patients who had undergone spinal instrumentation surgery.
Summary of Background Data. Although PCT and NLR are commonly used as markers for bacterial infection, the diagnostic value of these factors for predicting SSI in the context of spinal instrumentation surgery has not been extensively investigated.
Methods. We retrospectively investigated 242 patients who underwent spinal instrumentation surgery and evaluated the significance of various postoperative measures for predicting SSI, including PCT and NLR. We then determined the diagnostic cut-off values for these markers in the prediction of SSI using receiver operating characteristic curve analysis.
Results. Among the 242 patients analyzed, 10 were diagnosed with infection. Even though univariate analysis showed that neutrophil percentage and NLR at 6 to 7 days postoperatively were significant predictors for SSI, PCT at 6 to 7 days postoperatively did not differ significantly between the SSI and non-SSI groups. The cut-off value used for neutrophil percentage at 6 to 7 days postoperatively was more than 69.0% sensitivity, 80.0%; specificity, 70.0%; area under the curve, 0.737. The cut-off value used for NLR at 6 to 7 days postoperatively was 3.87 (sensitivity, 70.0%; specificity, 73.2%; area under the curve, 0.688).
Conclusion. Neutrophil percentage and NLR at 6 to 7 days postoperatively were more useful markers than PCT at 6 to 7 days postoperatively for early prediction of SSI in patients who had undergone spinal instrumentation surgery. Therefore, routine use of PCT as a predictor of postoperative infection is not supported by the results of this study.
Level of Evidence: 4

Outcomes at Skeletal Maturity of 34 Children With Scoliosis Treated With a Traditional Single Growing Rod

01-12-2019 – Bouthors, Charlie; Gaume, Mathilde; Glorion, Chistophe; Miladi, Lotfi

Journal Article

Study Design. Retrospective case series.
Objectives. To analyze the outcomes at skeletal maturity of patients treated with a single traditional growing rod (GR). To compare results of patients according to whether posterior spinal fusion (PSF) was performed at treatment completion.
Summary of Background Data. Few studies examined the end results of GRs at skeletal maturity. There is no agreement on requirement of PSF at GR treatment completion.
Methods. Clinical and radiological analysis of consecutive patients with severe and/or progressive scoliosis treated initially with traditional single GR. Group comparisons of patients with PSF and without fusion surgery at treatment completion.
Results. Thirty-four patients underwent traditional single GR implantation at a median age of 11.7 years. Median follow-up was 6.5 years. At last follow-up, T1-S1 distance was increased by a median 116 mm (P < 0.001) and median major curve Cobb angle was changed from 55° preoperatively to 30° (P < 0.001). Complications included 26 rod fractures, 1 implant prominence, 4 proximal junctional kyphosis, 2 proximal hook dislodgments, and 2 wound infections. At the beginning our experience, PSF was performed systematically in 17 patients. Relying on spinal ankylosis, 17 patients were subsequently not fused at GR treatment completion (single GR removed N = 2, single GR retained N = 7, dual GR surgery N = 8). There were no statistical differences between groups in improvements of radiological parameters from preoperative GR insertion to last follow-up. No GR fracture occurred after dual GR surgery.
Conclusion. Single GR allows curve control and promotes spinal growth. Dual GR is, however, recommended for rod fracture prevention and better correction maintenance. In patients with satisfactory deformity correction at skeletal maturity, one may consider retaining dual GR instead of performing PSF.
Level of Evidence: 4

Two-Level Osteotomy for the Corrective Surgery of Severe Kyphosis From Ankylosing Spondylitis: A Retrospective Series

01-12-2019 – Zhong, Woquan; Chen, Zhongqiang; Zeng, Yan; Sun, Chuiguo; Li, Weishi; Qi, Qiang; Guo, Zhaoqing

Journal Article

Study Design. Retrospective study.
Objective. To describe the treatment results of patients with severe ankylosing spondylitis (AS) kyphosis who underwent two-level osteotomy and correction surgery.
Summary of Background Data. The best solution for the fixed kyphotic deformity of AS is corrective osteotomy. Many osteotomy options are available: pedicle subtraction osteotomy (PSO), Smith-Peterson osteotomy (SPO), and vertical column resection (VCR). These procedures all provide multiplanar deformity correction. Nevertheless, when the AS deformity is severe, an additional osteotomy site to get more correction, achieve more ideal, and smooth curvature of the spine than single osteotomy.
Methods. From May, 2008 to August, 2016, 19 patients of severe AS kyphosis underwent two-level spinal osteotomy and correction surgery. The patients had an average kyphosis angle greater than 90°. The radiological features and clinical evaluation, including Oswestry Disability Index (ODI), visual analog scale (VAS), and Scoliosis Research Society (SRS)-22 components were assessed before surgery and at follow-up. The patients underwent either one-level PSO combined with one-level SPO (n = 9) or two-level PSO (n = 10).
Results. The height was increased after surgery in all patients (P < 0.05). The median follow-up was 24 months. The kyphosis angle improved from 92.0 ± 16.6° to 30.0 ± 17.2°. The chin-brow vertical angle improved from 37.6 ± 19.2° to –0.6 ± 2.5°. The sacral slope improved from 3.9 ± 11.8° to 21.7 ± 7.4°. Sagittal imbalance improved from 241.4 ± 115.3 mm to 74.6 ± 48.5 mm (P < 0.05). Lumbar lordosis improved from –3.9 ± 20.8° to 29.4 ± 14.1° (all P < 0.05). There were significant improvements in the ODI, VAS, and all components of SRS-22 (all P < 0.05). All patients with pseudarthrosis (n = 5) underwent PSO + SPO and achieved satisfactory results. Six complications were observed perioperatively, but without permanent sequelae.
Conclusion. Two-level osteotomy and correction procedure can achieve satisfactory results in severe AS kyphosis. PSO + SPO could be a good option for patients with pseudarthrosis because of relatively easier and faster operation.
Level of Evidence: 4

Lower SRS Mental Health Scores are Associated With Greater Preoperative Pain in Patients With Adolescent Idiopathic Scoliosis

01-12-2019 – Hwang, Steven W.; Pahys, Joshua M.; Bastrom, Tracey P.; Lonner, Baron S.; Newton, Peter O.; Samdani, Amer F.; Harms Study Group§

Journal Article

Study Design. Retrospective review of a prospectively collected multicenter database.
Objective. The aim of this study was to investigate factors associated with low preoperative SRS pain scores.
Summary of Background Data. The prevalence of preoperative pain in patients with adolescent idiopathic scoliosis (AIS) has become increasingly evident and is a primary concern for patients and families. Greater preoperative pain is associated with more postoperative pain; however, less is understood about what contributes to preoperative pain.
Methods. A prospectively collected, multicenter database was queried for patients with AIS. Patients were divided into 2 cohorts based on preoperative SRS pain scores: ≤ 3 (Pain cohort), 4 to 5 (No Pain cohort). Univariate analysis was performed identifying which factors were associated with a low preoperative SRS score and used for a CART analysis.
Results. Of 2585 patients total, 2141 (83%) patients had SRS pain scores of 4 to 5 (No Pain) and 444 (17%) had SRS pain scores ≤3 (Pain). Female sex, older age, greater % body mass index, larger lumbar curves, greater T5–12 kyphosis, and lower mental health scores were associated with greater preoperative pain. In multivariate CART analysis, lower mental health SRS scores (P = 0.04) and older age (P = 0.003) remained significant, with mental health scores having the greatest contribution. In subdividing the mental health component questions, anxiety-related questions appeared to have the greatest effect followed by mood/depression (SRS Question 13: OR 2.04; Q16: OR 1.35; Q7: OR 1.31; Q3: OR 1.20).
Conclusion. Anxiety and mood are potentially modifiable risk factors that have the greatest impact on pre- and postoperative pain. These results can be used to identify higher-risk patients and develop preoperative therapeutic protocols to improve postoperative outcomes.
Level of Evidence: 3

Comparison of Radiological Features and Clinical Characteristics in Scoliosis Patients With Chiari I Malformation and Idiopathic Syringomyelia: A Matched Study

01-12-2019 – Shen, Jianxiong; Tan, Haining; Chen, Chong; Zhang, Jianguo; Lin, Youxi; Rong, Tianhua; Jiao, Yang; Liang, Jinqian; Li, Zheng

Study Design. Retrospective study.
Objective. To compare syrinx characteristics, scoliotic parameters, and neurological deficits between Chiari I malformation (CIM) and idiopathic syringomyelia (IS) in the scoliotic population.
Summary of Background Data. CIM and IS are common in neuromuscular scoliosis patients; however, differences in syrinx characteristics, scoliotic parameters, and neurological deficits between CIM and IS are unclear.
Methods. Thirty-six patients with scoliosis secondary to CIM were enrolled retrospectively and matched with 36 IS patients for sex, age, scoliosis classification, and Cobb angle. Information on radiographic features of scoliosis and syrinx and neurological deficits was systematically collected.
Results. Sex, age, and coronal, and sagittal scoliosis parameters did not differ between the CIM and IS groups. The CIM group had a longer syrinx (12.9 ± 4.0 vertebral levels vs. 8.7 ± 5.5 vertebral levels, P < 0.001), a higher cranial extent (3.6 ± 2.2 vs. 5.2 ± 3.5, P = 0.027), and a lower caudal extent (15.6 ± 2.9 vs. 13.0 ± 4.6, P = 0.006) than the IS group, despite no differences in syrinx/cord (S/C) ratio or syrinx classification. No differences in neurological deficits were identified between the CIM and IS patients.
Conclusion. With demographic and scoliotic coronal parameters matched, the CIM patients had a longer syrinx, located at a higher cranial and lower caudal level, compared with the IS group. No significant differences in syrinx S/C ratio, sagittal features of scoliosis, or neurological deficits were detected between the two groups.
Level of Evidence: 3

Predicting the Natural Course of Hemivertebra in Early Childhood: Clinical Significance of Anteroposterior Discordance Based on Three-dimensional Analysis

01-12-2019 – Chang, Sam Yeol; Nam, Yunjin; Lee, Jeongik; Lee, Na-Kyoung; Chang, Bong-Soon; Lee, Choon-Ki; Kim, Hyoungmin

Journal Article

Study Design. A retrospective cohort, radiographic study.
Objective. The aim of this study was to compare the progression of scoliosis owing to single hemivertebra (HV) during early childhood, according to the anteroposterior discordance obtained from the three-dimensional computed tomography (3D-CT) studies.
Summary of Background Data. Previous studies have utilized 3D-CT for the classification of congenital spinal deformities and have introduced the concept of two types of deformity: unison and discordant anomalies. However, there have been no further studies on the clinical significance of these discordant deformities, especially in the identification of deformities that will progress and require an operation.
Methods. We retrospectively analyzed 97 cases of single HV with thoracolumbar scoliosis, diagnosed in children before the age of 3 years and followed up past the age of 6 years. The segmentation of the anterior and posterior components, and anteroposterior discordance of the HV were evaluated using 3D-CT images. Coronal segmental curve angle (SCA) and balance were measured using whole spine plain radiographs.
Results. Using 3D-CT, 41 (42.3%) cases of unison HV and 56 (57.7%) discordant HV were identified. Unison HV comprised 21 (21.6%) cases of fully segmented (FS) unison HV and 20 (20.6%) cases of semi-segmented unison HV with corresponding anterior and posterior segmentation. Fifty-six cases of discordant HV were further classified into 4 different types. In the 86 patients who were followed without operation between the ages of 3 and 6 years, the average progression of SCA was significantly larger in FS unison HV (one-way analysis of variance, P < 0.001). Ten of 86 (11.6%) patients showed a coronal imbalance at the age of 6 years, but the proportion of patients with coronal imbalance was not significantly different among the deformity types.
Conclusion. Anteroposterior discordance on 3D analysis is a useful indicator for the progression of congenital scoliosis due to single HV in early childhood.
Level of Evidence: 4

Cervical Spine Fractures: Who Really Needs CT Angiography?

01-12-2019 – Fourman, Mitchell S.; Shaw, Jeremy D.; Vaudreuil, Nicholas J.; Dombrowski, Malcolm E.; Wawrose, Rick A.; Boakye, Lorraine A.T.; Alarcon, Louis H.; Lee, Joon Y.; Donaldson, William F. III

Journal Article

Study Design. Retrospective cohort study.
Objective. Compare a novel two-step algorithm for indicating a computed tomography angiography (CTA) in the setting of a cervical spine fracture with established gold standard criteria.
Summary of Background Data. As CTA permits the rapid detection of blunt cerebrovascular injuries (BCVI), screening criteria for its use have broadened. However, more recent work warns of the potential for the overdiagnosis of BCVI, which must be considered with the adoption of broad criteria.
Methods. A novel two-step metric for indicating CTA screening was compared with the American College of Surgeons guidelines and the expanded Denver Criteria using patients who presented with cervical spine fractures to a tertiary-level 1 trauma center from January 1, 2012 to January 1, 2016. The ability for each metric to identify BCVI and posterior circulation strokes that occurred during this period was assessed.
Results. A total of 721 patients with cervical fractures were included, of whom 417 underwent CTAs (57.8%). Sixty-eight BCVIs and seven strokes were diagnosed in this cohort. All algorithms detected an equivalent number of BCVIs (52 with the novel metric, 54 with the ACS and Denver Criteria, P = 0.84) and strokes (7/7, 100% with the novel metric, 6/7, 85.7% with the ACS and Denver Criteria, P = 1.0). However, 63% fewer scans would have been needed with the proposed screening algorithm compared with the ACS or Denver Criteria (261/721, 36.2% of all patients with our criteria vs. 413/721, 57.3% with the ACS standard and 417/721, 57.8%) with the Denver Criteria, P < 0.0002 for each).
Conclusion. A two-step criterion based on mechanism of injury and patient factors is a potentially useful guide for identifying patients at risk of BCVI and stroke after cervical spine fractures. Further prospective analyses are required prior to widespread clinical adoption.
Level of Evidence: 4.

Benchmarks of Duration and Magnitude of Opioid Consumption After Common Spinal Procedures: A Database Analysis of 47,823 Patients

01-12-2019 – Cook, David J.; Kaskovich, Samuel; Pirkle, Sean; Ho, Alisha; Conti Mica, Megan; Shi, Lewis; Lee, Michael

Study Design. A retrospective cohort study performed in a nationwide insurance claims database.
Objective. This study aimed to examine duration and magnitude of postoperative opioid prescriptions following common spinal procedures.
Summary of Background Data. Postoperative opioid prescription practices vary widely among providers and procedures and standards of care are not well-established. Previous work does not adequately quantify both duration and magnitude of opioid prescription.
Methods. Forty seven thousand eight hundred twenty three patients with record of any of four common spinal procedures in a nationwide insurance claims database were stratified by preoperative opioid use into three categories: “opioid naive,” “sporadic user,” or “chronic user,” defined as 0, 1, or 2+ prescriptions filled in the 6 months preceding surgery. Those with record of subsequent surgery or readmission were excluded. Duration of opioid use was defined as the time between the index surgery and the last record of filling an opioid prescription. Magnitude of opioid use was defined as milligram morphine equivalents (MME) filled by 30 days post-op, converted to 5 mg oxycodone pills for interpretation.
Results. Opioid naive patients were less likely than chronic opioid users to fill any opioid prescription after surgery (63–68% naive vs. 91–95% chronic, P < 0.001), and when they did, their prescriptions were smaller in magnitude (76–91 pills naive vs. 127–152 pills chronic). One year after surgery, 15% to 18% of opioid naive and 50% to 64% of chronic opioid users continued filling prescriptions.
Conclusion. Opioid naive patients use less postoperative opioids, and for a shorter period of time, than chronic users. This study serves as a normative benchmark for examining postoperative opioid use, which can assist providers in identifying patients with opioid dependence. Importantly, this work calls out the high risk of opioid exposure, as 15% to 18% of opioid naive patients continued filling opioid prescriptions 1 year after surgery.
Level of Evidence: 3

National Trends in the Surgical Management of Lumbar Spinal Stenosis in Adult Spinal Deformity Patients

01-12-2019 – Al Jammal, Omar M.; Delavar, Arash; Maguire, Kathleen R.; Hirshman, Brian R.; Wali, Arvin R.; Kazzaz, Majd; Pham, Martin H.

Journal Article

Study Design. This is a retrospective analysis of national administrative hospital data.
Objective. This study examines national trends in the surgical management of lumbar spinal stenosis (LSS) in patients with and without coexisting scoliosis between 2010 and 2014. The study also examines revision rates for LSS procedures.
Summary of Background Data. There is wide variability in the surgical management of patients with LSS, with and without coexisting spinal deformity.
Methods. Data were obtained from the Healthcare Cost and Utilization Projects National Inpatient Sample Database. International Classification of Diseases 9th revision- Clinical Modification codes were used to identify all patients with a primary diagnosis of lumbar spinal stenosis. These patients were divided into two groups: 1) LSS alone and 2) LSS with coexisting scoliosis. The two groups were examined for one of three surgical outcomes: 1) decompression alone (discectomy, laminectomy), 2) simple fusion, and 3) complex fusion (>three vertebrae or 360° fusion). The groups were then further examined for revision operations. National Inpatient Sample discharge weights were applied where relevant.
Results. In 2014 national estimates of discharged patients indicated 76,275 patients with a primary diagnosis of LSS (population rate, 23.9; in the elderly (65+) the age-adjusted population rate was 95.4). Of these patients, 88.5% were managed through primary surgery (34.6% decompression, 47.2% simple fusion, 5.7% complex fusion). Between 2010 and 2014, the percentage of decompression decreased from 47.5% to 34.6%, the percent of simple fusion increased from 35.3% to 47.2%, and the percent of complex fusion increased from 5.7% to 7.1% (P < 0.01). In patients with coexisting scoliosis, lumbar spinal stenosis was predominantly managed by simple fusion and complex fusion (15.5% decompression, 51.9% simple fusion, 27.3% complex fusion, in 2014). Revision rates were highest among patients without scoliosis managed with complex fusion (15.8% in 2014) compared with patients with scoliosis (8.8% in 2014). Patients with scoliosis who underwent decompression only had revision rates of 1.7% and 0.62% in 2010 and 2014, respectively.
Conclusion. We observed a leveling-off of the rate of operation for patients with a primary diagnosis of LSS at around 88%. There was an increase in the rate of fusion and a decrease in the rate of decompression across all patient groups. We report no difference in revision rates between patients with and without scoliosis, except in those undergoing a complex fusion.
Level of Evidence: 3

Validation of the Disabilities of the Arm, Shoulder, and Hand in Patients Undergoing Cervical Spine Surgery

01-12-2019 – Khalifeh, Jawad M.; Akbari, Syed Hassan A.; Khandpur, Umang; Johnston, William; Wright, Neill M.; Hawasli, Ammar H.; Dorward, Ian; Santiago, Paul; Ray, Wilson Z.

Study Design. Retrospective cohort study.
Objective. To evaluate the performance and convergent validity of the disabilities of the arm, shoulder, and hand (DASH) in comparison with the visual analog scale (VAS) for pain, and neck disability index (NDI) in patients undergoing cervical spine surgery.
Summary of Background Data. Neck-specific disability scales do not adequately assess concurrent upper extremity involvement in patients with cervical spine disorders. The DASH is a patient-reported outcomes (PRO) instrument designed to measure functional disability due to upper extremity conditions but has additionally been shown to perform well in patients with neck disorders.
Methods. We identified patients who underwent cervical spine surgery at our institution between 2013 and 2016. We collected demographic information, clinical characteristics, and PRO measures—DASH, VAS, NDI—preoperatively, as well as early and late postoperatively. We calculated descriptive statistics and changes from baseline in PROs. Correlation coefficients were used to quantify the association between PRO measures. The analysis was stratified by radiculopathy and myelopathy diagnoses.
Results. A total of 1046 patients (52.8% male) with PROs data at baseline were included in the analysis. The mean age at surgery ± SD was 57.2 ± 11.3 years, and postoperative follow-up duration 12.7 ± 10.7 months. The most common surgical procedure was anterior cervical discectomy and fusion (71.1%). Patients experienced clinically meaningful postoperative improvements in all PRO measures. The DASH showed moderate positive correlations with VAS preoperatively (Spearman rho = 0.43), as well as early (rho = 0.48) and late postoperatively (rho = 0.60). DASH and NDI scores were strongly positively correlated across operative states (Preoperative rho = 0.74, Early Postoperative rho = 0.78, Late Postoperative rho = 0.82). Stratified analysis by preoperative diagnosis showed similar within-groups trends and pairwise correlations. However, radiculopathy patients experienced larger magnitude early and late change scores.
Conclusion. The DASH is a valid and responsive PRO measure to evaluate disabling upper extremity involvement in patients undergoing cervical spine surgery.
Level of Evidence: 3

Comparative and Predictor Analysis of 30-day Readmission, Reoperation, and Morbidity in Patients Undergoing Multilevel ACDF Versus Single and Multilevel ACCF Using the ACS-NSQIP Dataset

01-12-2019 – Katz, Austen David; Mancini, Nickolas; Karukonda, Teja; Cote, Mark; Moss, Isaac L.

Journal Article

Study Design. Retrospective cohort study.
Objective. The aim of this study was to determine the differences in 30-day readmission, reoperation, and morbidity for patients undergoing multilevel anterior cervical discectomy and fusion (ACDF) or single and multilevel anterior cervical corpectomy and fusion (ACCF).
Summary of Background Data. Despite increasing rates of surgical treatment of cervical spine disease, few studies have compared outcomes by surgical technique. To the best of our knowledge, this is the only large-scale administrative database study that directly evaluates early outcomes between multilevel ACDF and single and multilevel ACCF.
Methods. Patients who underwent ACDF and ACCF were identified using the NSQIP database. Multivariate regression was utilized to compare rates of readmission, reoperation, morbidity, and specific complications between surgical techniques, and to evaluate for predictors of primary outcomes.
Results. We identified 15,600 patients. ACCF independently predicted (P < 0.001) greater reoperation (odds ratio OR = 1.876) and morbidity (OR = 1.700), but not readmission, on multivariate analysis. ACCF was also associated with greater rates of transfusion (OR = 3.273, P < 0.001) and DVT/thrombophlebitis (OR = 2.852, P = 0.001). ACCF had significantly (P < 0.001) greater operative time and length of stay. In the cohort, increasing age (P < 0.001), diabetes (P = 0.025), chronic obstructive pulmonary disease (P = 0.027), disseminated cancer (P = 0.009), and American Society of Anesthesiologists (ASA) class ≥3 (P < 0.001) predicted readmission. Age (P = 0.011), female sex (P = 0.001), heart failure (P = 0.002), ASA class ≥3 (P < 0.001), and increased creatinine (P = 0.044), white cell count (P = 0.033), and length of stay (P < 0.001) predicted reoperation. Age (P < 0.001), female sex (P = 0.002), disseminated cancer (P = 0.010), ASA class ≥3 (P < 0.001), increased white cell count (P = 0.036) and length of stay (P < 0.001), and decreased hematocrit (P < 0.001) predicted morbidity. Within ACDF, three or more levels treated compared to two levels did not predict poorer 30-day outcomes.
Conclusion. Compared to multilevel ACDF, ACCF was associated with an 88% increased odds of reoperation and 70% increased odds of morbidity; readmission was similar between techniques. Older age, higher ASA class, and specific comorbidities predicted poorer 30-day outcomes. These findings can guide surgical solution given specific factors.
Level of Evidence: 3

The Use of Patient-Reported Outcome Measurement Information System Physical Function to Predict Outcomes Based on Body Mass Index Following Minimally Invasive Transforaminal Lumbar Interbody Fusion

01-12-2019 – Yoo, Joon S.; Hrynewycz, Nadia M.; Brundage, Thomas S.; Singh, Kern

Study Design. Retrospective.
Objective. To determine clinical outcomes in obese patients compared with non-obese patients utilizing Patient-Reported Outcome Measurement Information System Physical Function (PROMIS PF) following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).
Summary of Background Data. Although obesity is a risk factor for poor outcomes after spinal fusion, there has not been a study to evaluate clinical outcomes of obese patients utilizing the PROMIS PF survey.
Methods. Patients undergoing MIS TLIF were stratified into three cohorts: non-obese (body mass index BMI ≤ 29.9 kg/m2), obese I (BMI = 30.0–34.9 kg/m2), and obese II–III (BMI ≥ 35.0 kg/m2). Demographic and perioperative characteristics were compared using chi-squared analysis and linear regression. Change in PROMIS PF scores was calculated using paired t tests. Differences in PROMIS PF scores at each postoperative timepoint and changes in PROMIS PF from baseline were compared using linear regression.
Results. One hundred eighty-six patients were included: 101 were non-obese, 41 were classified as obese I, and 44 were classified as obese II–III. Obese patients were more likely to be diabetic. Otherwise, no significant differences in demographic and perioperative characteristics were identified. Patients with higher BMIs reported significantly lower PROMIS PF scores at preoperative and all postoperative timepoints. However, patients experienced similar improvements through 6-month follow-up in PROMIS PF scores regardless of BMI. For the non-obese cohort, the change in the postoperative PROMIS PF score from baseline was significant at every postoperative timepoint. However, for the obese I and obese II–III cohorts, the change in the PROMIS PF score from baseline was significant at the 3-month and 6-month timepoints, but not at the 6-week timepoint.
Conclusion. Patients with higher BMI had lower preoperative PROMIS PF scores and experienced similar improvement in PROMIS PF scores in the postoperative period. This study established that PROMIS PF may be utilized to evaluate the recovery of obese patients following MIS TLIF.
Level of Evidence: 3

Technical and Nontechnical Skills in Surgery: A Simulated Operating Room Environment Study

01-12-2019 – Pfandler, Michael; Stefan, Philipp; Mehren, Christoph; Lazarovici, Marc; Weigl, Matthias

Journal Article

Study Design. Observational simulation study.
Objective. The goal of this study was to investigate the relationship between technical and nontechnical skills (NTS) in a simulated surgical procedure.
Summary of Background Data. Although surgeons’ technical and NTS during surgery are crucial determinants for clinical outcomes, little literature is available in spine surgery. Moreover, evidence regarding how surgeons’ technical and NTS are related is limited.
Methods. A mixed-reality and full-scale simulated operating room environment was employed for the surgical team. Eleven surgeons performed the vertebroplasty procedure (VP). Technical skills (TS) were assessed using Objective Structured Assessment of Technical Skill scores and senior expert-evaluated VP outcome assessment. NTS were assessed with the Observational Teamwork Assessment for Surgery. Kendall-Tau-b tests were performed for correlations. We further controlled the influence of surgeons′ experience (based on professional tenure and number of previous VPs performed).
Result. Surgeons’ NTS correlated significantly with their technical performance (τ = 0.63; P = 0.006) and surgical outcome scores (τ = 0.60; P = 0.007). This association was attenuated when controlling for surgeons’ experience.
Conclusion. Our results suggest that spine surgeons with higher levels of TS also apply better communication, leadership, and coordination behaviors during the procedure. Yet, the role of surgeons′ experience needs further investigation for improving surgeons’ intraoperative performance during spine surgery.
Level of Evidence: 3

Complications with Minimally Invasive Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis in the Obese Population

01-12-2019 – Buyuk, Abdul Fettah; Shafa, Eiman; Dawson, John M.; Schwender, James D.

Journal Article

Study Design. A level-3 retrospective cohort analysis.
Objective. The aim of this study was to describe obesitys effect on complications and outcomes in degenerative spondylolisthesis patients treated by minimally invasive transforaminal lumbar interbody fusion (MI TLIF).
Summary of Background Data. Obesity is associated with a greater complication rate among lumbar spine surgery patients. Poor clinical outcomes might likewise be supposed, but the association is not well established. Minimally invasive techniques have been developed to reduce complications and improve clinical outcomes in comparison to traditional open techniques.
Methods. We reviewed 134 consecutive patients with degenerative spondylolisthesis undergoing MI TLIF. Subjects were grouped into nonobese (N = 65) and obese (N = 69) cohorts. The obese group was further subdivided by BMI. Patient demographics, perioperative complications, and outcome scores were collected over a minimum of 24 months. Four periods (intraoperative, postoperative hospitalization, 6-month, and 24-month postoperative) were assessed.
Results. Cohort demographics were not significantly different, but it was noted that obese patients had more major comorbidities than nonobese patients. There was no difference in intraoperative complications between the two groups. The in-hospital complication rate was significantly greater in the obese group. The 6-month postoperative complication rate was not different between cohorts. Wound drainage was most common and noted only in the obese cohort. Complications at 24 months were not different but did trend toward significance in the obese for recurrence of symptoms and total complications. Functional outcome was better among nonobese subjects compared with obese subjects at every interval (significant at 6 and 12 months). Back pain scores were significantly better among nonobese subjects than obese subjects at 24 months, but Leg Pain scores were not different.
Conclusions. MI TLIF can be safely performed in the obese population despite a higher in-hospital complication rate. Knowledge of common complications will help the treatment team appropriately manage obese patients with degenerative spondylolisthesis.
Level of Evidence: 3

TO THE EDITOR:

01-12-2019 – Hu, Bailong; Zou, Xiaohua

Journal Article

No abstract available

TO THE EDITOR:

01-12-2019 – Hua, Wenbin; Yang, Cao

Journal Article

No abstract available