Ossification Of Posterior Longitudinal Ligament Research Articles

Pestle Needle Combined with Transforaminal Endoscopic Discectomy for the Treatment of Ossification of Posterior Longitudinal Ligament of Thoracic Vertebra in a Case

Pestle Needle Combined with Transforaminal Endoscopic Discectomy for the Treatment of Ossification of Posterior Longitudinal Ligament of Thoracic Vertebra in a Case

Letter to the Editor: Commentary on Progression of Ossification of Posterior Longitudinal Ligament After Anterior Cervical Discectomy and Fusion in Military Patients Exposed to Minor Trauma (Korean J Neurotrauma 2022;18:254-267).

Letter to the Editor: Commentary on Progression of Ossification of Posterior Longitudinal Ligament After Anterior Cervical Discectomy and Fusion in Military Patients Exposed to Minor Trauma (Korean J Neurotrauma 2022;18:254-267).

Are clinical outcomes affected by laminoplasty method and K-line in patients with cervical ossification of posterior longitudinal ligament? A multicenter study

BackgroundOpen-door laminoplasty (ODL) and French-door laminoplasty (FDL) are the main laminoplasty techniques used to treat cervical ossification of the posterior longitudinal ligament (C-OPLL). However, few studies have compared the outcomes of ODL and modified FDL (mFDL) for C-OPLL. We explored the differences in outcomes between ODL and mFDL for C-OPLL and analyzed the technical efficacy of each procedure in patients with K-line (+) or (−) C-OPLL.MethodsFrom January 2010 to December 2015, 202 patients with K-line (+) or (−) C-OPLL were retrospectively recruited from 4 institutions. Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) score, JOA score recovery rate, operative time, blood loss, and complications. Univariate analysis and binary logistic regression models were adjusted for confounding factors.ResultsTwo hundred patients (mFDL, n = 69; ODL, n = 131) with a median follow-up of 42 months (range 36–54 months) were included. The postoperative JOA score significantly improved in both groups (P < 0.05). After adjusting for confounding factors, there was a statistically significant difference in blood loss (≥ 300 mL) between the two groups (P = 0.005), but there was no significant difference in the postoperative JOA score (≥ 14) (P = 0.062), JOA score recovery rate (≥ 0.82) (P = 0.187), or operative time (≥ 90 min) (P = 0.925). C5 palsy tended to occur more often in the mFDL group, although the difference was not significant (P > 0.05). The stratified analysis of the K-line status showed more blood loss in K-line (+) patients who underwent mFDL, but there was no significant difference in the postoperative JOA score, JOA score recovery rate, or operative time between the ODL and mFDL groups. Additionally, there was no significant difference in blood loss, postoperative JOA score, JOA score recovery rate, or operative time among all patients with K-line (+) or (−) C-OPLL in both groups.ConclusionsBoth ODL and mFDL are effective for patients with C-OPLL. However, more blood loss tends to occur during mFDL. This study showed no significant difference in the operative time or incidence of complications between the two techniques. The efficacy of ODL and mFDL was not affected by the K-line status (+ or −) in patients with C-OPLL.

Clinical progression of ossification of the ligamentum flavum in thoracic spine: a 10- to 11-year follow-up study.

Thoracic ossification of ligamentum flavum (TOLF) can be asymptomatic and progress insidiously. But, long-term follow-up results of clinical progression of TOLF are still unknown. The clinical progression of 81 patients with TOLF at our center, followed for 10 to 11 (mean, 10.3) years from May 2010 to November 2021, were analyzed. Among them, 51 patients with thoracic myelopathy were caused by single- or multi-segment TOLF, and received partial TOLF resection (30 patients) or total TOLF resection (21 patients). The remaining 30 patients showed TOLF on imaging examinations, but TOLF was not the responsible compressing factor causing myelopathy and with no TOLF resection. The mJOA score (total 11 scores) and spinal operation were used to evaluate the clinical progression at follow-up. During the 10- to 11-year follow-up of 81 TOLF patients, 71 (87.7%) had no deterioration of neurological function, and 10 (12.3%) patients had deterioration of neurological function and had another spinal operation, including only 4 (4.9%) suffered thoracic myelopathy caused by the progression of TOLF; 6 (7.4%) for other spinal diseases: 2 (2.5%) had fall damage and acute spinal cord injury at the TOLF level; 2 (2.5%) had thoracic myelopathy caused by ossification of posterior longitudinal ligament (OPLL); 2 (2.5%) had cervical spondylosis and received cervical operation. Most TOLF (87.7%) patients had no clinical progression and received no reoperations for TOLF in the ten-year dimension (mean, 10.3years). Narrow spinal canal for TOLF increases the risk of traumatic paraplegia.

Vertebral Body Sliding Osteotomy for theTreatment of Symptomatic Ossification of Posterior Longitudinal Ligament: 2-DimensionalOperative Video.

Vertebral Body Sliding Osteotomy for theTreatment of Symptomatic Ossification of Posterior Longitudinal Ligament: 2-DimensionalOperative Video.

IL-6/Stat3 suppresses osteogenic differentiation in ossification of the posterior longitudinal ligament via miR-135b-mediated BMPER reduction.

Interleukin-6 (IL-6) has been reported to induce osteogenic differentiation of mesenchymal stem cells for increasing bone regeneration, while the role of IL-6 in osteogenic differentiation during ossification of the posterior longitudinal ligament (OPLL) remains to be determined. The current study aims to explore the downstream mechanism of IL-6 in cyclic tensile strain (CTS)-stimulated OPLL, which involves bioinformatically identified microRNA-135b (miR-135b). Initially, we clinically collected posterior longitudinal ligament (PLL) and ossified PLL tissues, from which ossified PLL cells were isolated, respectively. The obtained data revealed a greater osteogenic property of ossified PLL than non-ossified PLL cells. The effect of regulatory axis comprising IL-6, Stat3, miR-135b, and BMPER on osteogenic differentiation of CTS-stimulated ossified PLL cells was examined with gain- and loss-of-function experiments. BMPER was confirmed as a target gene to miR-135b. Knockdown of BMPER or overexpression of miR-135b inhibited the osteogenic differentiation of CTS-induced ossification in PLL cells. Besides, IL-6 promoted the post-transcriptional process to mature miR-135b via Stat3 phosphorylation. In conclusion, IL-6 inhibited CTS-induced osteogenic differentiation by inducing miR-135b-mediated inhibition of BMPER through Stat3 activation.

Diffuse Idiopathic Skeletal Hyperostosis Prevalence, Characteristics, and Associated Comorbidities: A Cross-Sectional Study of 1815 Whole Spine CT Scans.

A Retrospective Study. To determine the prevalence and characteristics of DISH using whole spine CT scans and to evaluate the association of DISH with co-morbidities and other ossified lesions. A retrospective study of whole-spine CT scans of polytrauma patients from 2018-2021 above the age of 20 years. The screening was done using modified Resnick criteria. Overall and age-specific prevalence, characteristics, and associations with obesity, diabetes mellitus (DM), ischemic heart disease (IHD), aortic calcification (AC), ossified posterior longitudinal ligament (OPLL), and ossified ligamentum flavum (OLF) were evaluated. Out of 1815 patients, 347 had DISH, with a prevalence rate of 19.1% and a mean age of 61.7 years. The highest prevalence of DISH was seen in individuals over 80 years of age (45.5%). The prevalence among males (20.2%) was higher than for females (14.9%). The most commonly involved level was T8-T9 (95.4%), followed by T9-T10 (91.9%), and the most common vertebra involved was T9 (96%). All the cases involving T9 had ossification on the right anterior aspect of the vertebral body. The presence of DM, high BMI, and IHD was found to be significantly higher in patients with DISH (P value < .001). The incidence of aortic calcification was 22.5%, OPLL was 13.3%, and OLF was 4.9% in patients with DISH. This study reports a prevalence rate of 19.1% for DISH, with the highest prevalence among individuals above 80 years of age (45.5%). DISH has a higher propensity to affect the right anterior aspect of the vertebral body in the thoracic spine and is strongly associated with obesity, DM, IHD, and AC.

Dural ossification associated with ossification of posterior longitudinal ligament in the cervical spine: a retrospective analysis.

Dural ossification (DO) is common in patients with ossification of the posterior longitudinal ligament (OPLL). The existence of DO makes surgery challenging and increases the risk of complications. The aim of this study was to investigate the incidence, distribution and radiological characteristics of DO associated with OPLL. From January 2017 to January 2019, 55 patients with cervical OPLL were treated in our single center using an anterior cervical approach microsurgery. Preoperative CT images of decompressed segments were evaluated to identify imaging signs of DO. The 'double-layer sign' (DLS), 'parenthese sign' (PS) and 'hook sign' (HS) were considered to be characteristic imaging findings of DO in OPLL. Two kinds of confusing signs (false double-layer) were identified. Nineteen segments from 15 patients with OPLL had DO related to OPLL. The incidence of DO in OPLL segments was 30.16% (19/63), and the incidence of DO in patients with OPLL was 27.27% (15/55). DO occurred at the intervertebral space level in 14 cases and at the posterior level of the vertebral body in 5 cases. The sensitivity and specificity of imaging diagnosis were 89.47% (17/19) and 81.82% (36/44), respectively. The positive predictive value was relatively low, 68.00% (17/25), due to the false-positive double-layer sign. The negative predictive value was 94.74% (36/38). DO was relatively common in cervical OPLL. DLS might be misdiagnosed. PS and HS can vividly and intuitively describe the imaging features of DO and have high diagnostic accuracy.

Evidence for a genetic contribution to the ossification of spinal ligaments in Ossification of Posterior Longitudinal Ligament and Diffuse idiopathic skeletal hyperostosis: A narrative review.

Diffuse Idiopathic Skeletal Hyperostosis (DISH) and Ossification of the Posterior Longitudinal Ligament (OPLL) are common disorders characterized by the ossification of spinal ligaments. The cause for this ossification is currently unknown but a genetic contribution has been hypothesized. Over the last decade, many studies on the genetics of ectopic calcification disorders have been performed, mainly on OPLL. Most of these studies were based on linkage analysis and case control association studies. Animal models have provided some clues but so far, the involvement of the identified genes has not been confirmed in human cases. In the last few years, many common variants in several genes have been associated with OPLL. However, these associations have not been at definitive levels of significance and evidence of functional significance is generally modest. The current evidence suggests a multifactorial aetiopathogenesis for DISH and OPLL with a subset of cases showing a stronger genetic component.

Stress Distribution on Spinal Cord According to Type of Laminectomy for Large Focal Cervical Ossification of Posterior Longitudinal Ligament Based on Finite Element Method.

Most studies on the ossification of the posterior longitudinal ligament (OPLL) using the finite element method were conducted in the neutral state, and the resulting decompression was judged to be good. As these studies do not reflect the actual behavior of the cervical spine, this study conducted an analysis in the neutral state and a biomechanical analysis during flexion and extension behaviors. After validation via the construction of an intact cervical spine model, the focal OPLL model was inserted into the C4–C5 segment and a simulation was performed. The neutral state was shown by applying a fixed condition to the lower part of the T1 and Y-axis fixed condition of the spinal cord and simulating spinal cord compression with OPLL. For flexion and extension simulation, a ±30-degree displacement was additionally applied to the top of the C2 dens. Accordingly, it was confirmed that spinal cord decompression did not work well during the flexion and extension behaviors, but rather increased. Thus, if patients with focal OPLL inevitably need to undergo posterior decompression, additional surgery using an anterior approach should be considered.

Analysis between preoperative cervical radiographic parameters represented by the K-line tilt and the short-term prognosis of laminoplasty for posterior longitudinal ligament ossification: A retrospective study.

ObjectivesTo investigate the relationship between preoperative radiographic parameters and the short-term prognosis of patients with cervical ossification of the posterior longitudinal ligament (OPLL) who underwent laminoplasty (LAMP).MethodsA retrospective analysis of Cervical OPLL 50 patients with K-line (+) OPLL with no cervical kyphosis who received LAMP was performed. Based on preoperative neutral position x-ray, the K-line tilt, C2–C7 SVA (sagittal vertical axis), CL (cervical lordosis), T1 slope, and T1 slope-CL were recorded. The JOA (Japanese orthopaedic association scores) score and the cervical kyphosis change were recorded 1 year after surgery. Patients were divided into good and poor prognosis groups according to the median (12.5) of the postoperative JOA score.ResultsThere were differences between the two groups in K-line tilt, C2–C7 SVA, and T1 slope (all ps < 0.05). There was a strong linear correlation between the three, K-Line tilt, JOA score, and C2–C7 SVA. The degree of influence of K-line tilt, C2–C7 SVA, T1 slope on postoperative JOA score was analyzed using multiple linear regression, and the absolute value of the standardized coefficient Beta were 0.550, 0.319, 0.185, respectively. There was no cervical kyphosis change 1 year after surgery.ConclusionAs preoperative cervical parameters, the influence of K-line tilt, C2–C7 SVA, and T1 slope on postoperative JOA score decreases in order. There was a linear relationship between preoperative K-line tilt and postoperative JOA score, implying that patients with cervical OPLL with high K-line tilt were not eligible for LAMP. K-line tilt was not predictive of cervical kyphosis change after LAMP in patients with OPLL at short-term follow-up.

Short term clinical observation of cervical anterior Hybrid surgery

To investigate the short-term clinical effect of the cervical anterior Hybrid surgery in the treatment of two-segment and three-segment cervical spondylosis. From January 2018 to January 2019, 108 patients who were performed anterior Hybrid surgery with cervical degenerative diseases were collected. The patients were divided into a two-segment group with 52 patients and a three-segment group with 56 patients according to surgical segments. In two-segment group, there were 24 males and 28 females, aged from 35 to 67 years old with an average of(45.94±14.67) years old. In three-segment group, there were 23 males and 33 females, aged from 32 to 65 years old with an average of (47.54±15.34) years old. The outcome indicators of the two groups were compared. Clinical indicators:neck disability index(NDI) was used to evaluate daily life ability, Japanese Orthopedic Association(JOA) score was used to evaluate neurological function improvement, visual analogue scale(VAS) was used to evaluate pain intensity, and general clinical results were graded according to Odom's score. Cervical range of motion (ROM), fusion and complications were measured by X-ray, CT and MRI. All operations were successfully completed and all patients were followed up for more than 12 months. The operation time of two-segment group and three-segment group were 95 to 180 min with an average of(152.30±44.74) min and 110 to 210 min with an average of (165.18±45.86) mins, the blood loss were 20 to 100 ml with an average of (32.88±8.75) ml and 20 to 150 ml with an average of(34.64±10.63) ml respectively which has no statistical differences between the two groups (P>0.05). Compared with those before surgery, NDI, JOA, VAS and Odom's scores between two groups were significantly improved at 12 months after operation(P<0.05). However, there was no significant difference in the NDI, JOA and Odom's scores between two groups (P>0.05), and VAS in three-segment group was higher than that in two-segment group. There was no significant difference in C3-C7 cervical mobility between two groups. Surgical incisions healed smoothly in all patients without complication such as spinal cord injury and cerebrospinal fluid leakage. The bone fusion of the two groups were 43 cases (82.69%) and 45 cases(80.35%) respectively. In two-segment group, there were 2 cases of adjacent segmental hyperosteogeny, and there were 3 cases of adjacent segmental hyperosteogeny and 1 case of adjacent posterior longitudinal ligament ossification in the three-segment group. In addition, in three-segment group, there was 1 case of looseness of implants with no obvious clinical symptoms. The anterior Hybrid surgery in treating multi-level cervical spondylosis could not only improve clinical symptoms of patients but also preserve mobility. Meanwhile, the efficacy and safety of Hybrid surgery in different multi-level cervical disc diseases are confirmed, proving its value in clinical practice.

49 DCM-Related Degenerative Spinal Changes in the Healthy: Meta-Analysis &amp; Comparison to a Symptomatic Cohort

Abstract Aim Degenerative cervical myelopathy (DCM) is a progressive cervical spinal cord injury brought about by mechanical stress from degenerative changes in the cervical spine. It is typically diagnosed on clinical symptoms, examination findings together with MRI findings. The objective was to determine the significance of category of degenerative pathology (identified in Nouri et al, 2017) to onset of DCM, by comparing symptomatic and asymptomatic populations. Method A systematic review and meta-analysis were conducted in accordance with the PRISMA guidelines, cognizant of their adaptation for epidemiological studies. A search strategy was used to identify original research carrying out MRI screening of cervical spines of asymptomatic patients in MEDLINE and Embase from 1985 to the present day. Results The search yielded a total of 1,098 studies of which 17 were included in this meta-analysis, covering a total of 5,059 patients. Ossification of posterior longitudinal ligament (pooled asymptomatic prevalence of 0.4%), enlargement of ligamentum flavum (pooled asymptomatic prevalence of 11.8%) and degenerative multilevel disc pathology (pooled asymptomatic prevalence of 64.5%, I2 100%) were found to be significantly lower in asymptomatic populations (factor of 25 times, 4 times and 1.5 times respectively), and thus associated with DCM. Conclusions Ossification of posterior longitudinal ligament and enlargement of ligamentum flavum were found to be markedly lower in asymptomatic populations, possibly significantly implicating ligamentous pathology in the onset of DCM. Understanding the natural history of DCM is a recognised research priority, and whilst these perspectives require further evaluation, they may be of significance to the evolving biomechanical understanding of the disease.

Imaging features of developmental stenosis of atlas with degenerative cervical myelopathy

Objective: To investigate the imaging features of patients with developmental stenosis of atlas (small atlas) complicated with degenerative cervical myelopathy and to explore the diagnostic criteria of small atlas. Methods: The clinical data of patients with degenerative cervical myelopathy treated by posterior cervical laminoplasty and resection of posterior arch of atlas from 2006 to 2020 in the Department of Orthopedics, Peking University Third Hospital were retrospectively analyzed. Sixteen cases had spinal cord compression at C1 level after the exclusion of ossification of cervical posterior longitudinal ligament (OPLL) and other pathology. These cases were suspected small atlas (small atlas group). Forty-six cases without posterior arch resection in the same period were selected as control group. The middle sagittal diameter of atlas and the vertical distance from posterior tubercle of atlas to occipitoaxial line under CT in both groups were compared. The sagittal diameter of the spinal canal at the atlas level under MRI, the Japanese Orthopaedic Association (JOA) score for functional state of cervical spine before operation and at last follow-up were also measured. Results: There were 9 males and 7 females in the small atlas group, aged (63±12) years. There were 21 males and 25 females in the control group, aged (57±10) years. The patients in both group were followed-up for at least one year. The sagittal diameter of atlas in the small atlas group was (26.4±3.1) mm, which was significantly smaller than that in the control group [(29.6±2.2) mm, P=0.010]. The vertical distance from the posterior tubercle of atlas to the occipitoaxial line in the small atlas group was larger than that in the control group[(6.79±1.17) mm vs (5.57±1.29) mm, P=0.001]. The diameter of atlas canal in the small atlas group was (8.25±1.44) mm which was significantly smaller than that in the control group [(13.00±1.66) mm, P<0.001]. The JOA score of the small atlas group before operation and at the last follow-up were both slightly lower than that in the control group (both P<0.05), but there was no significant difference in the recovery rate of JOA score between the two groups (61.9% vs 66.0%, P=0.066). Among the 16 cases in the small atlas group, 5 cases of occipital-axial connection were located at the posterior 1/3 of the posterior arch of atlas, and 11 cases of occipital-axial connection were completely located at the posterior arch of atlas. Conclusions: The effective sagittal diameter of atlas is smaller in small atlas group which can lead to more severe cervical myelopathy. The presence of a small atlas should be highly suspected when the sagittal diameter of atlas canal is less than 26 mm under CT. The existence of the small atlas should be alert when the occipitalaxial line is located at the dorsal 1/3 or behind of the posterior arch of atlas.

Bibliometric and visualized analysis of research on ossification of posterior longitudinal ligament

Objectives: Through the analysis of the publication years, countries, institutions, keywords, references, authors, and journals, we found the main directions and hot topics of Ossification of the posterior longitudinal ligament research. Methods: Using the Science Citation Index Expanded (SCI E) database of the Web Of Science (WOS) Core Collection database, publications on OPLL research were retrieved from 1995 to 2019, and bibliometric methodology was used to research the source data. VOSviewer software were used to analyze the publication trend in OPLL research. Network maps were made by using VOS viewer, to discover the relationship between institutions, keywords, references, authors, and journals. Results: 1525 literatures were retrieved in the field of OPLL by using the database of the Web Of Science (WOS). The country and institution with the largest number of publications are Japan and Hirosaki University (Japan). The most co-cited document was “Operative Results and Postoperative Progression of Ossification among Patients with Ossification of Cervical Posterior Longitudinal Ligament”, authored by Hirabayashi K, published in the journal “Spine”. Hirabayashi K was also the most co-cited author. The relationship between co-cited authors was also awfully close and active. The most articles about OPLL were published in SPINE, which is also the most co-cited journal. Conclusions: Japan contributed the most publications. The overall trend of literature publication on OPLL was increasing year by year. By summarizing keywords, co-cited keywords, references, and co-cited references, it was not difficult to find the surgical method and the factors that affect the long-term postoperative effect were the hotspots of research.

An Institutional Experience and Literature Review on Iatrogenic Major Vascular Injury in Neurosurgery: Proposal of a Management Algorithm.

Major vessel injury is among the most dreaded complications of any neurosurgical procedure. Once intraoperatively tamponaded, it can present in the form of pseudoaneurysm, dissecting aneurysm or complete occlusion of vessel. These injuries are often associated with very high morbidity and mortality. The literature available on this topic is limited and our understanding remains limited. In this article, we present our surgical experience with iatrogenic aneurysms and present a review of literature. We conducted a retrospective analysis of all patients with major vessel injury during surgery from a prospectively maintained database from January 2012 to February 2020. A total of 15 patients developed iatrogenic aneurysms following a major vessel injury during various neurosurgical procedures. The most common vessel injured was vertebral artery (n = 9) in craniovertebral junction (CVJ) anomalies and ossification of posterior longitudinal ligament (OPLL) followed by internal carotid artery injury (n = 5) in sellar and parasellar pathologies. One patient developed basilar artery injury during endoscopic third ventriculostomy (ETV). Eight patients had pseudoaneurysm and seven had dissecting aneurysm with or without complete thrombosis of the involved artery. A total of two patients died after vascular injury and remaining thirteen patients survived and discharged. The adage "prevention is better than cure" applies most aptly in such cases. Any major vessel injury should be followed by immediate angiography and subsequent early management. The endovascular management is more favorable as these aneurysms are difficult to clip due to the absence of a neck and fragile wall.

Clinical Characteristics of Patients with Ossification of the Posterior Longitudinal Ligament and a High OP Index: A Multicenter Cross-Sectional Study (JOSL Study).

Background: The purpose of this study was to clarify the clinical features of ossification of the posterior longitudinal ligament (OPLL) and extreme ossification at multiple sites. Methods: This prospective study involved patients with a diagnosis of cervical OPLL at 16 institutions in Japan. Patient-reported outcome measures, including responses on the Japanese Orthopaedic Association (JOA) Cervical Myelopathy Evaluation Questionnaire (JOA-CMEQ), JOA Back Pain Evaluation Questionnaire (JOA-BPEQ), and visual analog scale pain score, were collected to investigate clinical status. In each patient, the sum of the levels at which OPLL was located (OP index) was evaluated on whole-spine computed tomography, along with ossification of other spinal ligaments including the anterior longitudinal ligament (OALL), ligament flavum (OLF), supra- and intraspinous ligaments (SSL), and diffuse idiopathic skeletal hyperostosis (DISH). The distribution of OP index values in the study population was investigated, and the clinical and radiologic characteristics of patients in the top 10% were assessed. Results: In total, 236 patients (163 male, 73 female; mean age 63.5 years) were enrolled. Twenty-five patients with OP index ≥ 17 were categorized into a high OP index group and the remainder into a moderate/low OP index group. There were significantly more women in the high OP index group. Patients in the high OP index group also had significantly poorer scores for lower extremity function and quality of life on the JOA-CMEQ and in each domain but not for body pain on the JOA-BPEQ compared with those in the moderate/low OP index group. Patients in the high OP index group had more OALL in the cervical spine and more OLF and SSL in the thoracic spine. The prevalence of DISH was also significantly higher in the high OP index group. In the high OP index group, interestingly, OPLL was likely to be present adjacent to DISH in the cervicothoracic and thoracolumbar spine, especially in men, and often coexisted with DISH in the thoracic spine in women. Conclusion: This prospective cohort registry study is the first to demonstrate the clinical and radiologic features of patients with OPLL and a high OP index. In this study, patients with a high OP index had poorer physical function in the lumbar spine and lower extremities and were also predisposed to extreme ossification of spinal ligaments other than the OPLL.

Perioperative Complications of Anterior Decompression with Fusion in Degenerative Cervical Myelopathy-A Comparative Study between Ossification of Posterior Longitudinal Ligament and Cervical Spondylotic Myelopathy Using a Nationwide Inpatient Database.

For ossification of the posterior longitudinal ligament (OPLL) and cervical spondylotic myelopathy (CSM), anterior decompression with fusion (ADF) can accurately achieve spinal decompression. However, the difference in perioperative complications in ADF between OPLL and CSM is poorly described. This study aimed to investigate the perioperative complication rates of patients with degenerative cervical myelopathy undergoing ADF, represented by OPLL and CSM, using a large national inpatient database. In the OPLL and CSM groups, postoperative complication (systemic and local) rates, reoperation rates, medical costs during hospitalization, and mortality after propensity score matching were compared. After matching, 1197 matched pairs were made. The incidence of total systemic complications was similar between both groups (OPLL, 12.4%; CSM, 12.2%). In the OPLL group, more perioperative local complications (cerebrospinal fluid leakage: CSFL, [OPLL, 2.7%; CSM, 0.3%] and surgical site infection: SSI [OPLL, 2.1%; CSM, 0.9%]) were detected, and the hospitalization cost was approximately $3200 higher than that in the CSM group. Moreover, medical costs were significantly higher in patients who experienced complications in both OPLL and CSM. The frequency of perioperative complications of OPLL and CSM in ADF was detailed using large real-world data. Compared to CSM, OPLL had more perioperative complications such as CSFL and SSI, and higher medical costs. Regardless of the disease, medical costs were significantly increased when perioperative complications occurred.

Postoperative progression of ligamentum flavum ossification after posterior instrumented surgery for thoracic posterior longitudinal ligament ossification: long-term outcomes during a minimum 10-year follow-up.

The authors sought to investigate clinical and radiological outcomes after thoracic posterior fusion surgery during a minimum of 10 years of follow-up, including postoperative progression of ossification, in patients with thoracic ossification of the posterior longitudinal ligament (T-OPLL). The study participants were 34 consecutive patients (15 men, 19 women) with an average age at surgery of 53.6 years (range 36-80 years) who underwent posterior decompression and fusion surgery with instrumentation at the authors' hospital. The minimum follow-up period was 10 years. Estimated blood loss, operative time, pre- and postoperative Japanese Orthopaedic Association (JOA) scores, and JOA score recovery rates were investigated. Dekyphotic changes were evaluated on plain radiographs of thoracic kyphotic angles and fusion levels pre- and postoperatively and 10 years after surgery. The distal junctional angle (DJA) was measured preoperatively and at 10 years after surgery to evaluate distal junctional kyphosis (DJK). Ossification progression at distal intervertebrae was investigated on CT. The Cobb angles at T1-12 were 46.8°, 38.7°, and 42.6°, and those at the fusion level were 39.6°, 31.1°, and 34.1° pre- and postoperatively and at 10 years after surgery, respectively. The changes in the kyphotic angles from pre- to postoperatively and to 10 years after surgery were 8.0° and 7.2° at T1-12 and 8.4° and 7.9° at the fusion level, respectively. The DJA changed from 4.5° postoperatively to 10.9° at 10 years after surgery. There were 11 patients (32.3%) with DJK during follow-up, including 4 (11.8%) with vertebral compression fractures at lower instrumented vertebrae or adjacent vertebrae. Progression of ossification of the ligamentum flavum (OLF) on the caudal side occurred in 8 cases (23.6%), but none had ossification of the posterior longitudinal ligament (OPLL) progression. Cases with OLF progression had a significantly lower rate of DJK (0% vs 38.5%, p < 0.01), a lower DJA (3.4° vs 13.2°, p < 0.01), and a smaller change in DJA at 10 years after surgery (0.8° vs 8.1°, p < 0.01). Posterior decompression and fusion surgery with instrumentation for T-OPLL was found to be a relatively safe and stable surgical procedure based on the long-term outcomes. Progression of OLF on the caudal side occurred in 23.6% of cases, but cases with OLF progression did not have DJK. Progression of DJK shifts the load in the spinal canal forward and the load on the ligamentum flavum is decreased. This may explain the lack of ossification in cases with DJK.

Prognostic Factors for Respiratory Dysfunction for Cervical Spinal Cord Injury and/or Cervical Fractures in Elderly Patients: A Multicenter Survey.

Retrospective Cohort Study. The purpose of this study was to investigate the prognosis of respiratory function in elderly patients with cervical spinal cord injury (SCI) and to identify predictive factors. We included 1353 cases of elderly cervical SCI patients collected from 78 institutions in Japan. Patients who required early tracheostomy and ventilator management and those who developed respiratory complications were defined as the respiratory disability group. Patients' background characteristics, injury mechanism, injury form, neurological disability, complications, and treatment methods were compared between the disability and non-disability groups. Multiple logistic regression analysis was used to examine the independent factors. Patients who required respiratory management for 6 months or longer after injury and those who died of respiratory complications were classified into the severe disability group and were compared with minor cases who were weaned off the respirator. A total of 104 patients (7.8%) had impaired respiratory function. Comparisons between the disabled and non-disabled groups and between the severe and mild injury groups yielded distinct trends. In multiple logistic regression analysis, age, blood glucose level, presence of ossification of posterior longitudinal ligament (OPLL), anterior vertebral hematoma, and critical paralysis were selected as independent risk factors. Age, OPLL, severe paralysis, anterior vertebral hematoma, hypoalbuminemia, and blood glucose level at the time of injury were independent factors for respiratory failure. Hyperglycemia may have a negative effect on respiratory function in this condition.