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Review of Basic Research about Ossification of the Spinal Ligaments Focusing on Animal Models. J Clin Med 2023; 12:jcm12051958. [PMID: 36902744 PMCID: PMC10003841 DOI: 10.3390/jcm12051958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/25/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
Ossification of the posterior longitudinal ligament (OPLL) is a heterotopic ossification that may cause spinal cord compression. With the recent development of computed tomography (CT) imaging, it is known that patients with OPLL often have complications related to ossification of other spinal ligaments, and OPLL is now considered part of ossification of the spinal ligaments (OSL). OSL is known to be a multifactorial disease with associated genetic and environmental factors, but its pathophysiology has not been clearly elucidated. To elucidate the pathophysiology of OSL and develop novel therapeutic strategies, clinically relevant and validated animal models are needed. In this review, we focus on animal models that have been reported to date and discuss their pathophysiology and clinical relevance. The purpose of this review is to summarize the usefulness and problems of existing animal models and to help further the development of basic research on OSL.
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Tang T, Zhu Z, He Z, Wang F, Chen H, Liu S, Zhan M, Wang J, Tian W, Chen D, Wu X, Liu X, Zhou Z, Liu S. DLX5
regulates the osteogenic differentiation of spinal ligaments cells derived from ossification of the posterior longitudinal ligament patients via
NOTCH
signaling. JOR Spine 2023. [DOI: 10.1002/jsp2.1247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Tao Tang
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Zhengya Zhu
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
| | - Zhongyuan He
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Fuan Wang
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Hongkun Chen
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
| | - Shengkai Liu
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Mingbin Zhan
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Jianmin Wang
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
| | - Wei Tian
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials Beijing Research Institute of Orthopaedics and Traumatology, Beijing Jishuitan Hospital Beijing China
| | - Dafu Chen
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials Beijing Research Institute of Orthopaedics and Traumatology, Beijing Jishuitan Hospital Beijing China
| | - Xinbao Wu
- Laboratory of Bone Tissue Engineering, Beijing Laboratory of Biomedical Materials Beijing Research Institute of Orthopaedics and Traumatology, Beijing Jishuitan Hospital Beijing China
| | - Xizhe Liu
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Zhiyu Zhou
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
| | - Shaoyu Liu
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital Sun Yat‐sen University Shenzhen China
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Orthopaedic Research Institute/Department of Spinal Surgery The First Affiliated Hospital of Sun Yat‐sen University Guangzhou China
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Tung NTC, He Z, Makino H, Yasuda T, Seki S, Suzuki K, Watanabe K, Futakawa H, Kamei K, Kawaguchi Y. Association of Inflammation, Ectopic Bone Formation, and Sacroiliac Joint Variation in Ossification of the Posterior Longitudinal Ligament. J Clin Med 2023; 12:jcm12010349. [PMID: 36615149 PMCID: PMC9821616 DOI: 10.3390/jcm12010349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/22/2022] [Accepted: 12/30/2022] [Indexed: 01/03/2023] Open
Abstract
Ossification of the posterior longitudinal ligament (OPLL) is considered a multifactorial condition characterized by ectopic new bone formation in the spinal ligament. Recently, its connections with inflammation as well as sacroiliac (SI) joint ankylosis have been discussed. Nevertheless, whether inflammation, spinal ligament ossification, and SI joint changes are linked in OPLL has never been investigated. In this study, whole-spinal computed tomography and serum high-sensitive C-reactive protein (hs-CRP) levels were obtained in 162 patients with cervical OPLL. Ossification lesions were categorized as plateau and hill shapes. Accordingly, patients were divided into plateau-shaped (51 males and 33 females; mean age: 67.7 years) and hill-shaped (50 males and 28 females; mean age: 67.2 years) groups. SI joint changes were classified into four types and three subtypes, as previously described. Interactions among ossification shapes, hs-CRP levels, and morphological changes in the SI joint were investigated. The plateau shape was more common in the vertebral segments (59.5%), compared to the hill shape, which was predominant in the intervertebral regions (65.4%). Serum hs-CRP levels in the plateau-shaped group (0.11 ± 0.10 mg/dL) were significantly higher than those in the hill-shaped group (0.07 ± 0.08 mg/dL). SI joint intra-articular fusion was the main finding in the plateau-shaped group and showed significantly higher hs-CRP levels compared to the anterior para-articular bridging, which more frequently occurred in the hill-shaped group. Our findings suggested a possible inflammation mechanism that might contribute to the new bone formation in OPLL, particularly the plateau shape.
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Affiliation(s)
- Nguyen Tran Canh Tung
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
- Department of Trauma and Orthopaedic Surgery, Vietnam Military Medical University, Hanoi 100000, Vietnam
| | - Zhongyuan He
- Innovation Platform of Regeneration and Repair of Spinal Cord and Nerve Injury, Department of Orthopaedic Surgery, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, China
| | - Hiroto Makino
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Taketoshi Yasuda
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Shoji Seki
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Kayo Suzuki
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Kenta Watanabe
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Hayato Futakawa
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Katsuhiko Kamei
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Yoshiharu Kawaguchi
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
- Correspondence: ; Tel.: +81-76-434-7353; Fax: +81-76-434-5035
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Ito K, Nagai S, Hachiya K, Takeda H, Kawabata S, Ikeda D, Kaneko S, Fujita N. Repeated Recurrence of Ligamentum Flavum Ossification After Posterior Spinal Surgery: A Case Report and Literature Review. JBJS Case Connect 2023; 13:01709767-202303000-00008. [PMID: 36821391 DOI: 10.2106/jbjs.cc.22.00267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
CASE Patients with myelopathy due to narrowing of the spinal canal with ossification of the ligamentum flavum (OLF) generally require surgical intervention, but surgical methods for OLF remain controversial. We discuss our experience regarding posterior fusion surgery with instrumentation for a patient with recurrent OLF at the same level after decompression surgery as well as describe the preoperative and postoperative course of this rare case. CONCLUSION Posterior decompression and fusion surgery is recommended as revision surgery for recurrent OLF at the same level after decompression surgery. A detailed surgical planning should be developed before surgery.
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Affiliation(s)
- Kei Ito
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Sota Nagai
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Kurenai Hachiya
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Hiroki Takeda
- Department of Spine and Spinal Cord Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Soya Kawabata
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Daiki Ikeda
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Shinjiro Kaneko
- Department of Spine and Spinal Cord Surgery, School of Medicine, Fujita Health University, Aichi, Japan
| | - Nobuyuki Fujita
- Department of Orthopaedic Surgery, School of Medicine, Fujita Health University, Aichi, Japan
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Hwang SH, Chung CK, Kim CH, Yang SH, Choi Y, Yoon J. Value of Additional Instrumented Fusion in the Treatment of Thoracic Ossification of the Ligamentum Flavum. J Korean Neurosurg Soc 2022; 65:719-729. [PMID: 35988925 PMCID: PMC9452387 DOI: 10.3340/jkns.2021.0167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 12/29/2021] [Indexed: 12/03/2022] Open
Abstract
Objective The ossification of the ligamentum flavum (OLF) is one of the major causes of thoracic myelopathy. Surgical decompression with or without instrumented fusion is the mainstay of treatment. However, few studies have reported on the added effect of instrumented fusion. The objective of this study was to compare clinical and radiological outcomes between surgical decompression without instrumented fusion (D-group) and that with instrumented fusion (F-group).
Methods A retrospective review was performed on 28 patients (D-group, n=17; F-group, n=11) with thoracic myelopathy due to OLF. The clinical parameters compared included scores of the Japanese Orthopedic Association (JOA), the Visual analogue scale of the back and leg (VAS-B and VAS-L), and the Korean version of the Oswestry disability index (K-ODI). Radiological parameters included the sagittal vertical axis (SVA), the pelvic tilt (PT), the sacral slope (SS), the thoracic kyphosis angle (TKA), the segmental kyphosis angle (SKA) at the operated level, and the lumbar lordosis angle (LLA; a negative value implying lordosis). These parameters were measured preoperatively, 1 year postoperatively, and 2 years postoperatively, and were compared with a linear mixed model.
Results After surgery, all clinical parameters were significantly improved in both groups, while VAS-L was more improved in the F-group than in the D-group (-3.4±2.5 vs. -1.3±2.2, p=0.008). Radiological outcomes were significantly different in terms of changes in TKA, SKA, and LLA. Changes in TKA, SKA, and LLA were 2.3°±4.7°, -0.1°±1.4°, and -1.3°±5.6° in the F-group, which were significantly lower than 6.8°±6.1°, 3.0°±2.8°, and 2.2°±5.3° in the D-group, respectively (p=0.013, p<0.0001, and p=0.037). Symptomatic recurrence of OLF occurred in one patient of the D-group at postoperative 24 months.
Conclusion Clinical improvement was achieved after decompression surgery for OLF regardless of whether instrumented fusion was added. However, adding instrumented fusion resulted in better outcomes in terms of lessening the progression of local and regional kyphosis and improving leg pain. Decompression with instrumented fusion may be a better surgical option for thoracic OLF.
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Qu X, Xu G, Hou X, Chen G, Fan T, Yang X, Chen Z. M1 Macrophage-Derived Interleukin-6 Promotes the Osteogenic Differentiation of Ligamentum Flavum Cells. Spine (Phila Pa 1976) 2022; 47:E527-E535. [PMID: 35044344 DOI: 10.1097/brs.0000000000004319] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 12/17/2021] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Basic experimental study. OBJECTIVE The aim of this study was to clarify the role of macrophages (Mφs) in the osteogenic differentiation of ligamentum flavum (LF) cells. SUMMARY OF BACKGROUND DATA Mφs and secreted factors are involved in the regulation of cell osteogenic differentiation, and play an important role in the process of heterotopic ossification. Whether Mφs are involved in the development of ossification of the ligamentum flavum (OLF) have not been reported. METHODS The expression of CD68+ Mφs in ossified LF tissue was identified by immunohistochemical staining. THP-1 cells were polarized to M1 and M2, and identified by flow cytometry and immunofluorescence. The alkaline phosphatase activity and osteogenic differentiation-related gene expression in LF cells were evaluated following incubation with each Mφs conditioned medium (CM). Enzyme-linked immunosorbent assay was used to detect the pro-inflammatory cytokines in the supernatants, and qPCR was used to detect the expression of the corresponding receptors in the LF cells after incubation with the CM. LF cells were induced with CM-M1 in the presence of neutralizing antibodies to further test whether cytokines secreted by M1 Mφs impacted their osteogenic differentiation. RESULTS CD68+ Mφs were found on the OLF samples. THP-1 cells were polarized into M1 and M2, and both M1 and M2 Mφs promoted the osteogenic differentiation of LF cells. The concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1 β, and IL-6 in M1 Mφ supernatants were greater than those in M2, and greater levels of these cytokine receptors were observed in LF cells induced with CM-M1 than those with CM-M2. Osteogenic differentiation of LF cells induced by CM-M1 decreased after IL-6 was neutralized; however, not after IL-1β and TNF-α were neutralized. CONCLUSION M1 Mφ-derived IL-6 promotes the osteogenic differentiation of LF cells, which may be a pathway in which Mφs regulate the osteogenic differentiation of LF cells.
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Affiliation(s)
- Xiaochen Qu
- Department of Orthopedics, First Affiliated Hospital of Dalian Medical University, Dalian, PR China
- Key Laboratory of Molecular Mechanism for Repair and Remodeling of Orthopadic Diseases, Liaoning Province, Dalian, PR China
- Department of Orthopedics, Peking University Third Hospital, Beijing, PR China
| | - Gang Xu
- Department of Orthopedics, First Affiliated Hospital of Dalian Medical University, Dalian, PR China
- Key Laboratory of Molecular Mechanism for Repair and Remodeling of Orthopadic Diseases, Liaoning Province, Dalian, PR China
| | - Xiaofei Hou
- Department of Orthopedics, Xuanwu Hospital of Capital Medical University, Beijing, PR China
| | - Guanghui Chen
- Department of Orthopedics, Peking University Third Hospital, Beijing, PR China
| | - Tianqi Fan
- Department of Orthopedics, Peking University Third Hospital, Beijing, PR China
| | - Xiaoxi Yang
- Department of Orthopedics, Peking University Third Hospital, Beijing, PR China
| | - Zhongqiang Chen
- Department of Orthopedics, Peking University Third Hospital, Beijing, PR China
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Cyclic Tensile Stress to Rat Thoracolumbar Ligamentum Flavum Inducing the Ossification of Ligamentum Flavum: An In Vivo Experimental Study. Spine (Phila Pa 1976) 2021; 46:1129-1138. [PMID: 34384088 DOI: 10.1097/brs.0000000000004087] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Western blot, reverse transcription-polymerase chain reaction (RT-PCR), radiological, and histological analyses of the rat ossification of ligamentum flavum (OLF) induced by cyclic tensile stress. OBJECTIVE The aim of this study was to induce the OLF using cyclic tensile stress to rat thoracolumbar ligamentum flavum, and to investigate the possible molecular mechanism of tension-induced OLF. SUMMARY OF BACKGROUND DATA Tensile stress has been considered as an important factor leading to the OLF. So far, however, no OLF induced by tension has been reported. METHODS Forty rats were randomly divided into five equal groups. For control groups, the blank and anesthesia groups were not subjected to tension. For experimental groups, the 4-, 8-, and 12-week groups were subjected to cyclic tensile stress of ligamentum flavum after abdominal anesthesia for 4 weeks, 8 weeks, and 12 weeks, respectively, using an original stress apparatus for rats. The radiological and morphological changes of rat spine, as well as the protein and mRNA expressions of CD44, bone morphogenetic protein-2 (BMP-2), integrin β3, collagen protein type I (COL1), osteopontin (OPN), runt-related transcription factor 2 (RUNX-2), and vascular endothelial growth factor (VEGF), were concerned. RESULTS The micro-CT showed OLF in the 4-, 8-, and 12-week group. The axial maximum occupied area of ossifications was 1.42 mm2, 3.35 mm2, and 7.28 mm2, respectively. In histopathology, chondrocytes proliferated in the experimental model; woven bone arose in the 8- and 12-week groups, and was more noticeable in the 12-week group. According to western blot and RT-PCR, the expressions of seven osteogenesis-related molecules were all increased in three experimental groups. CONCLUSION Cyclic tensile stress to the ligamentum flavum in rats can induce the OLF, and the longer the duration, the more visible the osteogenesis. The upregulation and synergism of osteogenesis-related molecules may contribute to the OLF induced by tensile stress.Level of Evidence: N/A.
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Thoracic ligamentum flavum ossification: a rare cause of spinal cord injury without tomographic evidence of trauma in a Caucasian patient. Case report and literature review. Spinal Cord Ser Cases 2021; 7:57. [PMID: 34244480 DOI: 10.1038/s41394-021-00422-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 11/09/2022] Open
Abstract
INTRODUCTION Acute spinal cord injury without tomographic evidence of vertebral fracture or dislocation in patients post trauma can represent a diagnostic challenge for the treating physician. The ossification of thoracic ligamentum flavum has been widely published as a cause of thoracic myelopathy, however its association with acute traumatic spinal cord injury is limited to isolated cases. CASE PRESENTATION we report a Caucasian 37-year-old man who suffered a high-energy thoracolumbar spine trauma in a motorcycle accident with acute paraplegia. He presented ossification of the ligamentum flavum between the thoracic vertebrae T10 and T11 with a decrease in the diameter of the vertebral canal as the only pathological finding. We treated the patient with early surgical release before 72 h of trauma. We performed a posterior approach with hemilaminectomy and T10-T11 flavectomy. Arthrodesis was done with T10-T11 pedicle screws. Postoperative neurological status improved from ASIA Impairment Scale (AIS) A to C with severe functional dependence. DISCUSSION Ossification of the ligamentum flavum should be considered in the differential diagnosis in patients presenting with acute traumatic spinal cord injury without tomographic evidence of trauma. A proper diagnosis in time is the key to decision making and treatment of spinal cord injury. Especially in adult patients, we must consider nontraumatic associated factors that could be involved in the spinal cord injury mechanism, such as ossification of the ligamentum flavum.
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Perna F, Geraci G, Mazzotti A, Stefanini N, Panciera A, Faldini C. Acute Presentation of Lumbar Spinal Stenosis Due to Ossified Ligamentum Flavum: The Possible Role of Spondylolisthesis: A Case Report. JBJS Case Connect 2019; 9:e0039. [PMID: 31211745 DOI: 10.2106/jbjs.cc.18.00039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CASE A 64-year-old woman with a history of low back pain, presented with acute gait impairment and lower limbs numbness without any history of trauma. Imaging studies revealed ossification of the ligamentum flavum (OLF) at L4-L5 and concomitant spondylolisthesis. Decompression surgery with en-bloc removal including the laminae, the ossified ligamentum flavum, and the medial facet and posterior stabilization was performed resulting in complete immediate recovery. CONCLUSIONS This report is the first to describe a case of an acute nontraumatic presentation of OLF associated with spondylolisthesis. OLF pathogenesis in still unknown, although several factors have been considered. According to the literature, operative treatment has demonstrated to be effective.
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Wang L, Jiang Y, Li M, Qi L. Postoperative Progression of Cervical Ossification of Posterior Longitudinal Ligament: A Systematic Review. World Neurosurg 2019; 126:593-600. [PMID: 30930321 DOI: 10.1016/j.wneu.2019.03.229] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 03/20/2019] [Accepted: 03/21/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVE The purpose of this study was to provide a systematic and comprehensive review of the existing literature regrading postoperative ossification of posterior longitudinal ligament (OPLL) progression. METHODS Using the PRISMA guidelines, we conducted an exhaustive review of electronic databases. Potential articles were screened and related information was extracted and analyzed. Twenty-four articles with low-quality evidence were included in the review. The findings of the literature review were divided into several groups: the relationship of surgery to OPLL progression; incidence and risk factors; timing and process of OPLL progression; the effect of additional instrumentation on progression; and neurologic deterioration related with progression. RESULTS There was no definitive conclusion for whether surgery could accelerate OPLL progression compared with the natural course. The incidence of postoperative OPLL progression was reported from 3.3% to 74.5%. Younger age, involvement of multiple levels and mixed or continuous types are recognized as risk factors. OPLL could progress transversely and longitudinally and progression in length appeared more significant than progression in thickness. Although radiologic OPLL progression was observed significantly more frequently after laminoplasty than after fusion surgery, whether additional instrumented fusion could suppress progression needs further research. Radiographic progression of OPLL did not positively correspond with neurologic deterioration. CONCLUSIONS The lack of high-level evidence makes it difficult to draw definite conclusions and further research and long-term follow-up clinical studies are needed to better understand postoperative OPLL progression.
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Affiliation(s)
- Liang Wang
- Department of Orthopaedic Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Yunpeng Jiang
- Department of Orthopaedic Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Mu Li
- Department of Orthopaedic Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Lei Qi
- Department of Orthopaedic Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China.
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Chen S, Zhu H, Wang G, Xie Z, Wang J, Chen J. Combined use of leptin and mechanical stress has osteogenic effects on ossification of the posterior longitudinal ligament. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2018; 27:1757-1766. [PMID: 29909551 DOI: 10.1007/s00586-018-5663-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 03/04/2018] [Accepted: 06/06/2018] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effects of leptin/leptin receptor (LepR) combined with mechanical stress on the development of ossification of the posterior longitudinal ligament (OPLL), which is a disease characterized by ectopic bone formation of the posterior longitudinal ligament (PLL) and can lead to radiculopathy and myelopathy. METHODS Six human samples of the PLL were analyzed for the expression of leptin and LepR by RT-PCR and western blotting. PLL cells were stimulated with leptin and mechanical stress delivered via a Flexcell tension system, and osteogenic differentiation was evaluated by RT-PCR and western blotting analysis of osteogenic marker expression as well as by alkaline phosphatase (ALP) staining and alizarin red S staining. Activation of mitogen-activated protein kinase (MAPK), Janus kinase (JAK) 2-signal transducer, activator of transcription (STAT) 3 and phosphatidylinositol 3-kinase (PI3K)-Akt was evaluated by western blotting. RESULTS Samples from the OPLL group had higher LepR mRNA and protein levels and lower leptin levels than those from healthy controls. Exposure to leptin and Flexcell increased the number of ALP-positive cells and calcium nodules in a dose-dependent manner; this effect was accompanied by upregulation of the osteogenic markers osteocalcin, runt-related transcription factor 2 (RUNX2) and osteopontin. Extracellular signal-regulated kinase, P38 MAPK, JAK2, STAT3, PI3K and Akt signaling, was also activated by the combined effects of leptin and mechanical stress. CONCLUSIONS Leptin and LepR are differentially expressed in OPLL tissues, and the combined use of leptin/LepR and mechanical stress promotes osteogenic differentiation of PLL cells via MAPK, JAK2-STAT3 and PI3K/Akt signaling. These slides can be retrieved under Electronic Supplementary Material.
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Affiliation(s)
- Shuai Chen
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, 310020, China
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China
| | - Haifeng Zhu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, 310020, China
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China
| | - Gangliang Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, 310020, China
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China
| | - Ziang Xie
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, 310020, China
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China
| | - Jiying Wang
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China
| | - Jian Chen
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, 310020, China.
- Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China.
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Rustagi T, Alonso F, Schmidt C, Oskouian RJ, Chapman JR, Tubbs RS, Fisahn C. Rapid Progression of Ossification of the Posterior Longitudinal Ligament After Anterior Cervical Discectomy and Fusion. World Neurosurg 2017; 110:11-16. [PMID: 29107718 DOI: 10.1016/j.wneu.2017.10.105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Ossification of the posterior longitudinal ligament (OPLL) has a reported incidence of 1.9%-4.3%. Disease progression is associated with surgery, with most studies focusing on OPLL progression after laminoplasty. The continued range of motion following surgery is believed to place strain on adjacent levels, driving calcification of the ligament. We present a case of marked progression of OPLL at levels adjacent to a previous anterior cervical discectomy and fusion. CASE REPORT A 59-year-old man initially presented for progressive loss of balance and dexterity and underwent a C4-6 anterior cervical discectomy and fusion procedure. Computed tomography performed 1 year postoperatively showed fusion across C4-6 with no evidence of OPLL at any level. Two years following index surgery, the patient reported right-side arm pain. Computed tomography revealed new minimal OPLL opposite the C3-4 level that was not causing cord compression. A sparing midline bilateral C3-7 laminotomy was performed to correct stenosis seen on magnetic resonance imaging. At 7 years after the index procedure, the patient presented with myelopathic symptoms exceeding symptoms at his index presentation. Computed tomography revealed marked progression of OPLL. The patient underwent C2-T2 posterior fusion with laminectomy from C2-C7 and responded well with gradual improvements in balance and arm pain after surgery. CONCLUSIONS Our report demonstrates that OPLL progression, which is largely reported following laminoplasty, may similarly occur following anterior cervical discectomy and fusion and supports the concept of motion-related OPLL progression.
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Affiliation(s)
- Tarush Rustagi
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA; Department of Spine Surgery, Indian Spinal Injuries Centre, Vasant Kunj, New Delhi, India
| | - Fernando Alonso
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
| | - Cameron Schmidt
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA; Seattle Science Foundation, Seattle, Washington, USA.
| | - Rod J Oskouian
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
| | - Jens R Chapman
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA
| | - R Shane Tubbs
- Seattle Science Foundation, Seattle, Washington, USA
| | - Christian Fisahn
- Swedish Neuroscience Institute, Swedish Medical Center, Seattle, Washington, USA; Seattle Science Foundation, Seattle, Washington, USA; Department of Trauma Surgery, BG University Hospital Bergmannsheil, Ruhr University Bochum, Bochum, Germany
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Qu X, Chen Z, Fan D, Sun C, Zeng Y, Guo Z, Qi Q, Li W. MiR-199b-5p inhibits osteogenic differentiation in ligamentum flavum cells by targeting JAG1 and modulating the Notch signalling pathway. J Cell Mol Med 2016; 21:1159-1170. [PMID: 27957826 PMCID: PMC5431140 DOI: 10.1111/jcmm.13047] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 10/30/2016] [Indexed: 12/20/2022] Open
Abstract
Ossification of the ligamentum flavum (OLF) is a pathology almost only reported in East Asian countries. The leading cause of OLF is thoracic spinal canal stenosis and myelopathy. In this study, the role of miR-199b-5p and jagged 1 (JAG1) in primary ligamentum flavum cell osteogenesis was examined. MiR-199b-5p was found to be down-regulated during osteogenic differentiation in ligamentum flavum cells, while miR-199b-5p overexpression inhibited osteogenic differentiation. In addition, JAG1 was found to be up-regulated during osteogenic differentiation in ligamentum flavum cells, while JAG1 knockdown via RNA interference caused an inhibition of Notch signalling and osteogenic differentiation. Moreover, target prediction analysis and dual luciferase reporter assays supported the notion that JAG1 was a direct target of miR-199b-5p, with miR-199b-5p found to down-regulate both JAG1 and Notch. Further, JAG1 knockdown was demonstrated to block the effect of miR-199b-5p inhibition. These findings imply that miR-199b-5p performs an inhibitory role in osteogenic differentiation in ligamentum flavum cells by potentially targeting JAG1 and influencing the Notch signalling pathway.
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Affiliation(s)
- Xiaochen Qu
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Zhongqiang Chen
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Dongwei Fan
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Chuiguo Sun
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Yan Zeng
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Zhaoqing Guo
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Qiang Qi
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
| | - Weishi Li
- Department of Orthopaedics, Peking University Third Hospital, Beijing, China
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Qu X, Chen Z, Fan D, Sun C, Zeng Y. MiR-132-3p Regulates the Osteogenic Differentiation of Thoracic Ligamentum Flavum Cells by Inhibiting Multiple Osteogenesis-Related Genes. Int J Mol Sci 2016; 17:ijms17081370. [PMID: 27556448 PMCID: PMC5000765 DOI: 10.3390/ijms17081370] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 08/08/2016] [Accepted: 08/16/2016] [Indexed: 12/29/2022] Open
Abstract
Ossification of the ligamentum flavum (OLF) is a disorder of heterotopic ossification of spinal ligaments and is the main cause of thoracic spinal canal stenosis. Previous studies suggested that miR-132-3p negatively regulates osteoblast differentiation. However, whether miR-132-3p is involved in the process of OLF has not been investigated. In this study, we investigated the effect of miR-132-3p and its target genes forkhead box O1 (FOXO1), growth differentiation factor 5 (GDF5) and SRY-box 6 (SOX6) on the osteogenic differentiation of ligamentum flavum (LF) cells. We demonstrated that miR-132-3p was down-regulated during the osteogenic differentiation of LF cells and negatively regulated the osteoblast differentiation. Further, miR-132-3p targeted FOXO1, GDF5 and SOX6 and down-regulated the protein expression of these genes. Meanwhile, FOXO1, GDF5 and SOX6 were up-regulated after osteogenic differentiation and the down-regulation of endogenous FOXO1, GDF5 or SOX6 suppressed the osteogenic differentiation of LF cells. In addition, we also found FOXO1, GDF5 and SOX6 expression in the ossification front of OLF samples. Overall, these results suggest that miR-132-3p inhibits the osteogenic differentiation of LF cells by targeting FOXO1, GDF5 and SOX6.
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Affiliation(s)
- Xiaochen Qu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Zhongqiang Chen
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Dongwei Fan
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Chuiguo Sun
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Yan Zeng
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
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Qu X, Chen Z, Fan D, Sun C, Zeng Y, Hou X, Ning S. Notch signaling pathways in human thoracic ossification of the ligamentum flavum. J Orthop Res 2016; 34:1481-91. [PMID: 27208800 DOI: 10.1002/jor.23303] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 05/19/2016] [Indexed: 02/04/2023]
Abstract
This study investigated the pathological process of Notch signaling in the osteogenesis of ligamentum flavum tissues and cells, and the associated regulatory mechanisms. Notch receptors, ligands, and target genes were identified by quantitative polymerase chain reaction (qPCR) in ligamentum flavum cells and immunohistochemistry in ligamentum flavum sections from ossification of the ligamentum flavum (OLF) patients and controls. The temporospatial expression patterns of JAG1/Notch2/HES1 in human ligamentum flavum cells during osteogenic differentiation were determined by qPCR. Lentiviral vectors for Notch2 overexpression and knockdown were constructed and transfected into ligamentum flavum cells before osteogenic differentiation to examine the function of Notch signaling pathways in the osteogenic differentiation of ligamentum flavum cells. Alkaline phosphatase, Runx2, Osterix, osteocalcin, and osteopontin mRNA levels, alkaline phosphatase activity, and Alizarin Red staining were used as indicators of osteogenic differentiation. JAG1/Notch2/HES1 mRNA levels were up-regulated in ligamentum flavum cells from OLF patients, which increased during osteogenic differentiation. Immunohistochemical analysis suggested positive Notch2 expression at the ossification front. Down-regulation of Notch2 expression decelerated osteogenic differentiation of ligamentum flavum cells, and Notch2 overexpression promoted osteogenic differentiation of ligamentum flavum cells. Expression of Runx2 and Osterix increased in a manner similar to that of Notch2 during osteogenic differentiation of ligamentum flavum cells, and Notch2 knockdown and overexpression influenced their expression levels. Notch signaling plays an important role in OLF, and Notch may affect the osteogenic differentiation of ligamentum flavum cells via interactions with Runx2 and Osterix.© 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1481-1491, 2016.
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Affiliation(s)
- Xiaochen Qu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Zhongqiang Chen
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Dongwei Fan
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Chuiguo Sun
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Yan Zeng
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Xiaofei Hou
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Shanglong Ning
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
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Clinical characteristics and surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum: a retrospective analysis of 85 cases. Spinal Cord 2015; 54:188-96. [PMID: 26238315 DOI: 10.1038/sc.2015.139] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN A retrospective comparative study. OBJECTIVES To describe the clinical features and radiological findings, to assess the safety and effectiveness of posterior decompressive laminectomy and resection of the ossification of the ligamentum flavum (OLF), and to determine which presurgical and surgical variables were most closely related to postsurgical prognosis of thoracic myelopathy (TM) caused by OLF in China. METHODS Eighty-five patients with the diagnosis of TM caused by OLF received surgical treatment from July 1998 to May 2012. Clinical data were collected from medical and operative records. Correlations between the surgical outcome and various factors were also analyzed. RESULTS All cases were followed up for a mean of 49.2 months (range, 24-190 months) postoperatively. The mean Japanese Orthopaedic Association score was 3.8 points preoperatively and 8.2 points at the final follow-up, yielding a mean recovery rate of 63.0%. Postoperative complications included transient neurological deficits (9 cases), persistent neurological deficits (4 cases), dural tears (17 cases), cerebrospinal fluid leakage (9 cases), wound dehiscence (2 cases) and wound infection (3 cases). The OLF level (middle thoracic), preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were important predictors of surgical outcome. CONCLUSIONS Biomechanical and anatomical factors may have a key role in thoracic OLF progression. Posterior decompressive laminectomy and resection of the OLF can be considered an effective, reliable and safe alternative procedure. The OLF level, preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were confirmed and significantly correlated with the surgical outcome.
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Surgical results and prognostic factors for thoracic myelopathy caused by ossification of ligamentum flavum: posterior surgery by laminectomy. Acta Neurochir (Wien) 2013; 155:1169-77. [PMID: 23584336 DOI: 10.1007/s00701-013-1694-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 03/21/2013] [Indexed: 10/27/2022]
Abstract
BACKGROUND Thoracic ossification of ligamentum flavum (TOLF) of the spine is characterized by a heterotopic bone formation in the thoracic ligamentum flavum, which causes slowly progressing spinal cord injury. Surgical decompression is the most common treatment of choice for patients with compressive myelopathy due to TOLF. However, the surgical outcome is not always satisfactory. METHODS To identify the predictors of surgical outcome, we retrospectively studied the associations between various clinical and radiological parameters and postoperative recovery in 78 patients who underwent decompressive laminectomy for thoracic myelopathy due to TOLF between October 1998 and June 2011. Surgical outcomes were assessed using modified Japanese Orthopedic Association (mJOA) recovery rate (RR)/outcome scores. RESULTS At a minimum of 1 year after surgery for TOLF treatment, the postoperative clinical scores showed statistically significant changes with improvement in the JOA scores. The results indicated that a longer duration of preoperative symptoms, fused-type TOLF, and the degree of compression of the anteroposterior diameter and ossified region (middle thoracic OLF) was related to poor prognosis. CONCLUSION Early diagnosis and sufficient surgical decompression improved the functional outcomes of TOLF patients. The surgical risk is relatively higher due to the tenuous blood supply of the spinal cord and the limited spinal canal volume of the middle thoracic spine extending from T4 to T9.
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Conte G, Viglianesi A, D'Amore A, Chiaramonte R, Pecoraro C, Nastasi L, Giuffrida S, Pero G, Chiaramonte I. Advanced Ossification of the Posterior Longitudinal Ligament in a Mildly Symptomatic Patient. Neuroradiol J 2011; 24:643-7. [DOI: 10.1177/197140091102400422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 04/26/2011] [Indexed: 11/17/2022] Open
Abstract
We describe the imaging findings of a man who developed neurologic symptoms due to ossification of the posterior longitudinal ligament with narrowing of the spinal canal and compression of the spinal cord. CT study allowed a detailed evaluation of the stenosis and the extension of the ossification while MRI gave an excellent visualization of the spinal lesions caused by spinal cord compression by the mass. The neurological status of patients with ossification of the posterior longitudinal ligament depends on many factors such as the degree of spinal canal stenosis, life style, accidental mechanical stress and trauma.
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Affiliation(s)
- G. Conte
- Department of Neurosciences, University of Catania; Catania, Italy
| | - A. Viglianesi
- Department of Radiology, University of Catania; Catania, Italy
| | - A. D'Amore
- Department of Neurosciences, University of Catania; Catania, Italy
| | - R. Chiaramonte
- Department of Otorhinolaryngology, University of Catania; Catania, Italy
| | - C. Pecoraro
- Department of Neurosciences, University of Catania; Catania, Italy
| | - L. Nastasi
- Department of Neurosciences, University of Catania; Catania, Italy
| | - S. Giuffrida
- Department of Neurosciences, University of Catania; Catania, Italy
| | - G. Pero
- Department of Neurosciences, University of Catania; Catania, Italy
| | - I. Chiaramonte
- Department of Neurosciences, University of Catania; Catania, Italy
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