Hao1 Is Not a Pathogenic Factor for Ectopic Ossifications but Functions to Regulate the TCA Cycle In Vivo

Ossification of the posterior longitudinal ligament (OPLL), a disease characterized by the ectopic ossification of a spinal ligament, promotes neurological disorders associated with spinal canal stenosis. While blocking ectopic ossification is mandatory to prevent OPLL development and progression, the mechanisms underlying the condition remain unknown. Here we show that expression of hydroxyacid oxidase 1 (Hao1), a gene identified in a previous genome-wide association study (GWAS) as an OPLL-associated candidate gene, specifically and significantly decreased in fibroblasts during osteoblast differentiation. We then newly established Hao1-deficient mice by generating Hao1-flox mice and crossing them with CAG-Cre mice to yield global Hao1-knockout (CAG-Cre/Hao1flox/flox; Hao1 KO) animals. Hao1 KO mice were born normally and exhibited no obvious phenotypes, including growth retardation. Moreover, Hao1 KO mice did not exhibit ectopic ossification or calcification. However, urinary levels of some metabolites of the tricarboxylic acid (TCA) cycle were significantly lower in Hao1 KO compared to control mice based on comprehensive metabolomic analysis. Our data indicate that Hao1 loss does not promote ectopic ossification, but rather that Hao1 functions to regulate the TCA cycle in vivo.

Degrees of Canal Stenosis, Levels of Interleukin-6 (IL-6) And C-Reactive Protein (CRP) Preoperative as Predictors of the Output of Neurogenic Claudication Outcome Score (NCOS) 8 Weeks Post-Decompression-Stabilization-Fusion in Degenerative Lumbar Spinal Stenosis Patients

Introduction: Lumbar Spinal Stenosis (LSS) or spinal stenosis is the most common spinal disease in elderly patients. LSS is also one of the leading causes of spinal surgery in the world. The problem that is often encountered is the limited predictor of outcomes that are considered affordable and accurate, so as to provide education to patients about possible output after the surgery process is carried out. Therefore, a predictor is needed that is considered accurate and affordable such as the degree of measurable canal stenosis of Magnetic resonance imaging (MRI), serum levels of C-Reactive Protein (CRP) and Interleukin-6 (IL-6) Method: This study used a prospective cohort design conducted to compare Neurogenic Claudication Outcome Score scores among people with degenerative lumbar canal stenosis whose post-decompression-stabilization-fusion had higher degrees of canal stenosis (measured through Schizas grading of Magnetic resonance Imaging/MRI) examinations), as well as high pre-operative CRP and IL-6 levels with those with normal CRP and IL-6 levels. From the population of lumbar spinal stenosis, the selection of samples was conducted consecutively sampling. After that, statistical tests in the form of descriptor tests, normality tests, risk factor assessments with 2x2 cross tabulation, and proportion comparison analysis using the Fisher Exact test. Result: Severe lumbar canal stenosis degrees resulted in worse NCOS 8 weeks postoperative than mild degrees of lumbar canal stenosis, with statistically significant differences (p=0.008; p < 0.05) and RR 6.4 (0.99-41.08). High CRP levels resulted in worse NCOS 8 weeks postoperative than mild lumbar degrees of canal stenosis, with statistically significantly differences (p=0.008; p < 0.05) and RR 6.4 (0.99-41.08). High pre-operative IL-6 levels resulted in worse NCOS 8 weeks postoperative than normal pre-operative IL-6 levels with statistically significantly differences (p=0.002; p < 0.05) and RR 8 (1.24-51.50). Conclusion: Degrees of preoperative (mild) canal stenosis, high pre-operative CRP levels, and high levels of pre-operative IL-6 were predictors for better 8-week NCOS scores in patients with post-decompression-stabilizing-fusion degenerative LSS disease. Key words: Degenerative lumbar spinal stenosis, IL-6, CRP, canal degree stenosis, NCOS.

Treatment of restenosis after lumbar decompression surgery: decompression versus decompression and fusion

OBJECTIVE The aim of this study was to compare perioperative complications and postoperative outcomes between patients with lumbar recurrent stenosis without lumbar instability and radiculopathy who underwent decompression surgery and those who underwent decompression with fusion surgery. METHODS For this retrospective study, the authors identified 2606 consecutive patients who underwent posterior surgery for lumbar spinal canal stenosis at eight affiliated hospitals between April 2017 and June 2019. Among these patients, those with a history of prior decompression surgery and central canal restenosis with cauda equina syndrome were included in the study. Those patients with instability or radiculopathy were excluded. The patients were divided between the decompression group and decompression with fusion group. The demographic characteristics, numerical rating scale score for low-back pain, incidence rates of lower-extremity pain and lower-extremity numbness, Oswestry Disability Index score, 3-level EQ-5D score, and patient satisfaction rate were compared between the two groups using the Fisher’s exact probability test for nominal variables and the Student t-test for continuous variables, with p < 0.05 as the level of statistical significance. RESULTS Forty-six patients met the inclusion criteria (35 males and 11 females; 19 patients underwent decompression and 27 decompression and fusion; mean ± SD age 72.5 ± 8.8 years; mean ± SD follow-up 18.8 ± 6.0 months). Demographic data and perioperative complication rates were similar. The percentages of patients who achieved the minimal clinically important differences for patient-reported outcomes or satisfaction rate at 1 year were similar. CONCLUSIONS Among patients with central canal stenosis who underwent revision, the short-term outcomes of the patients who underwent decompression were comparable to those of the patients who underwent decompression and fusion. Decompression surgery may be effective for patients without instability or radiculopathy.

A Comparative Study on Efficacies of Posterior Microscopic Mini-open and Open Technique for Thoracolumbar Burst Fractures Accompanied With Severe Traumatic Spinal Stenosis

Purpose To compare the efficacies of minimal invasive decompression by posterior microscopic mini-open technique combined with percutaneous pedicle fixation (hereafter MOT) and traditional open surgeries in patients with severe traumatic spinal canal stenosis resulting from AO Type A3 or A4 thoracolumbar burst fractures and provide references for clinical treatment. Methods The clinical materials of 133 patients with severe traumatic spinal canal stenosis caused by AO Type A3 or A4 thoracolumbar burst fractures who underwent MOT (group A) or traditional open surgery (group B) were retrospectively enrolled. The patient demographic and radiological data were analyzed between the two groups. Results A total of 64 patients were finally recruited in this study. There were no significant differences in gender, age, follow-up time, injury mechanism, injured level, Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, American Spinal Injury Association (ASIA) score, Visual analogue scale (VAS) score and hospital stay between the two groups (P>0.05). After procedures, the prevertebral height ratio (PHR), the Cobb angle, and the mid-sagittal canal diameter compression ratio (MSDCR) in two groups were significantly improved (P<0.05). Meanwhile, group A with little intraoperative bleeding volume, and the VAS score improved better at post-operation and last follow up, but the operative time was longer (P<0.05). The PHR, the Cobb angle in the two groups at the post-operation and last follow up without significantly different (P>0.05), the MSDCR was improved at last follow up when compared with the value at post-operation (P<0.05). However, the Cobb angle in group A was well maintained than in group B at last follow up (P<0.05) and the MSDCR in group B at last follow up improved better than in group A (P<0.05). Conclusions Both the MOT and traditional open surgery can treat AO type A3 and A4 thoracolumbar burst fractures accompanied with severe traumatic spinal stenosis effectively. The MOT has advantages including minimal invasion, extremely fine spinal canal decompression, lower intraoperative bleeding volume and obvious pain relief. We suggest that MOT should be preferentially selected for AO type A3 or A4 thoracolumbar burst fractures accompanied with severe traumatic spinal stenosis.

Lumbar spinous process-splitting technique for ligamentum flavum cyst removal: the first use in Europe.

Background Laminotomy for lumbar stenosis is a well-defined procedure and represents a routine in every neurosurgical department. It is a common experience that the mono- or bilateral paraspinal muscles detachment together with supra and interspinous ligaments injury can lead to postoperative pain. In literature has been reported the application at the level of the lumbar spine of a minimally invasive technique defined as lumbar spinous process-splitting technique (LSPST). Methods In the current study, we present a case series of 12 patients that underwent LSPSL from September 2019 to April 2020. Two patient suffering from ligamentum flavum cyst, 8 patients with single level lumbar canal stenosis (LCS) and two patients with two-level LCS. The approach was mini-open, with reduced soft tissue dissection and without paraspinal muscles injury. Moreover, a novel morphological classification of postoperative muscle atrophy is proposed as well as a volumetric analysis of the decompression achieved. Conclusion At our knowledge, this is the first description of this surgical technique and the first LSPSL case series in Europe. Furthermore, cases of ligamentum flavum cyst removal using this safe and effective technique are not yet reported. Abbreviations Lumbar canal stenosis (LCS), lumbar spinous process-splitting technique (LSPST), minimally invasive spine surgery (MISS)

Is Dynamic Spino-Pelvic Alignment During Gait Associated with Quality of Life in Patients with Degenerative Lumbar Spinal Canal Stenosis?

This study aims to investigate the relationship between dynamic alignment of the spine and pelvis during gait and quality of life (QOL) in lumbar spinal canal stenosis (LSS) patients. We evaluated QOL using the Oswestry Disability Index (ODI), trunk and hip muscle strength as physical function, static spinal alignment, and dynamic spinal/pelvic alignment during gait. The relationship between the ODI score and physical function or static and dynamic alignment were examined. A total of 30 preoperative patients with LSS were participated in this study. ODI score significantly correlated with trunk extension strength (r = -0.559, p = 0.002), hip extension strength (r = -0.473, p = 0.011), maximum flexion angle of spine during gait (r = -0.551, p = 0.002) and maximum anterior tilt angle of pelvis (r = 0.528, p = 0.004). Multiple regression analysis showed that trunk extension strength (standardized β; - 0.35), maximum spinal flexion angle (standardized β; - 0.51) and hip extension strength (standardized β; - 0.40) significantly affected the ODI score, with adjusted coefficient of determination of 0.62. The results of this study showed that the LSS patients with weak hip or trunk extensor muscles, a greater angle of pelvic tilt or a less spinal flexion during gait had a lower QOL.

Functional outcome in operated patients of multilevel lumbar canal stenosis and use of HRQoL role in depicting the anxiety and its correlation with the pain

Background Lumbar canal stenosis (LCS) is a degenerative spinal disease of elderly people, and it not only impairs the mechanical activity but also alters the economic and mental status of the patients indirectly. This is single-center observational prospective study conducted for 2 years and included 30 consecutive operated patients of multilevel LCS patients and excluded the patients with single-level LCS, with primary LCS or with grade II subluxation. We analyzed the various measurement indices used for the surgical outcome assessment as ED-5D 5L and OLBPDI (Oswestry low back pain disability index). Statistical analysis was done using SPSS (Statistical Package for Social Sciences) Version 21.0 statistical Analysis Software. The independent t test, post hoc analysis, Wilcoxon signed rank statistic test and RM-ANOVA test were also applied. Result Most patients have improvement in pain and all the components of HRQoL (health-related quality of life) after surgery, which was further improved in mean follow-up of 1 year. Our study also suggested that the patients with higher anxiety/depression have higher pain intensity and low HRQoL, which was persistent in postoperative period (p < .001). Conclusion ED-5D 5L and OLBPD are good indices to assess all the components of quality of life and give valuable information overall. Anxiety has shown important correlation with the pain component in both preoperative and postoperative phase.