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Kenichi Shinomiya - One of the best experts on this subject based on the ideXlab platform.
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Updates on ossification on Posterior Longitudinal Ligament. Electrophysiological diagnosis of spinal cord dysfunction in ossification of Posterior Longitudinal Ligament
Clinical calcium, 2009Co-Authors: Shigenori Kawabata, Atsushi Okawa, Shoji Tomizawa, Kenichi ShinomiyaAbstract:It is extremely difficult to make a correct diagnosis of the responsible lesion in multilevel continuous and mixed-type ossification of the Posterior Longitudinal Ligament (OPLL) even after magnetic resonance imaging (MRI) . Understanding the function of the preoperative spinal cord is crucial for surgical planning and electrophysiological diagnosis of spinal cord function is useful in such cases. Also, intraoperative spinal cord monitoring is required for cervical OPLL surgery because OPLL patients show postoperative neurological deterioration more frequently than any other pathogenesis.
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Long-term results of the anterior floating method for cervical myelopathy caused by ossification of the Posterior Longitudinal Ligament
Spine, 2001Co-Authors: Tadashi Matsuoka, Isakichi Yamaura, Yoshiro Kurosa, Osamu Nakai, Shigeo Shindo, Kenichi ShinomiyaAbstract:STUDY DESIGN Results of the anterior floating method used to decompress ossification of the Posterior Longitudinal Ligament were studied for an average postoperative interval of 13 years. OBJECTIVE To investigate the long-term results of the anterior floating method used to manage ossification of the Posterior Longitudinal Ligament. SUMMARY OF BACKGROUND DATA The anterior floating method is a technique that differs from the extirpation method used to manage ossification of the Posterior Longitudinal Ligament. Reports of the long-term results from anterior decompression used to manage cervical ossification of the Posterior Longitudinal Ligament are rare. METHODS The anterior floating method was used to decompress cervical ossification of the Posterior Longitudinal Ligament in 63 patients. These patients were followed for more than 10 years with neurologic evaluations using a scoring system proposed by the Japanese Orthopedic Association (JOA score). RESULTS The recovery rate was 66.5% at 10 years and 59.3% at 13 years, the time of the final survey. Operative outcomes most closely reflected the preoperative duration and severity of myelopathy (JOA score) and the preoperative cross-sectional area of the spinal cord. There was no correlation with the canal narrowing ratio or the thickness of ossification of the Posterior Longitudinal Ligament. Delayed deterioration was attributed to an original inadequate decompression and progression of ossification of the Posterior Longitudinal Ligament outside the original operative field. There was no evidence of significant recurrent ossification of the Posterior Longitudinal Ligament within the margins of prior decompression. CONCLUSIONS The anterior floating method appears to yield adequate long-term outcomes when used to manage ossification of the Posterior Longitudinal Ligament.
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Selecting a surgical method for thoracic myelopathy caused by ossification of the Posterior Longitudinal Ligament.
Spine, 1996Co-Authors: Yoshiro Kurosa, Isakichi Yamaura, Osamu Nakai, Kenichi ShinomiyaAbstract:Study Design. The authors classified typical distributional patterns of ossification of the Posterior Longitudinal Ligament of the thoracic spine in 1) central part of S-curve, 2) just above apical vertebra, and 3) combined with ossification of Ligamentum flavum below apical vertebra. The results of the surgical methods selected according to the author's classification were compared with those of previous reports. Objectives. To establish the criteria for selecting an appropriate surgical method for ossification of the Posterior Longitudinal Ligament of the thoracic spine. Summary of Background Data. Poor surgical results for ossification of the Posterior Longitudinal Ligament of middle or lower thoracic spine have been reported, but the unsuccessful location and curve has not been strictly defined. Methods. The authors studied postsurgical results in 26 cases of thoracic myelopathy caused by ossification of the Posterior Longitudinal Ligament. They also investigated radiographs of 111 cases, including 85 patients under observation, and examined the relationships between thoracic spine alignment and ossification of the Posterior Longitudinal Ligament distribution. Results. Twenty-three patients treated with methods conforming to the author's criteria achieved satisfactory recovery in walking ability except for one patient. The results of the other three patients who underwent surgery with nonconforming methods were uneven. Conclusion. Posterior decompression, as well as anterior decompression, is effective in the first pattern in the cervivothoracic region. In case of the second pattern, the responsible ossification of the Posterior Longitudinal Ligament always lies one or two levels above the apical vertebra and should be removed by anterior approach, regardless of the extent of kyphosis. Transthoracic anterior decompression surgery is considered the best method for most patients under the second and third patterns.
Hideshige Moriya - One of the best experts on this subject based on the ideXlab platform.
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Proliferating Cell Nuclear Antigen in Hypertrophied Spinal Ligaments: Immunohistochemical Localization of Proliferating Cell Nuclear Antigen in Hypertrophied Posterior Longitudinal Ligament of the Cervical Spine
Spine, 1998Co-Authors: Hiroyuki Motegi, Sumio Goto, Masashi Yamazaki, Atsuo Mikata, Hideshige MoriyaAbstract:Study Design. An experimental immunohistochemical investigation using an antibody for proliferating cell nuclear antigen. Surgically-extirpated specimens of Posterior Longitudinal Ligament tissues from patients with hypertrophy of the Posterior Longitudinal Ligament and other disorders of the cervical spine were analyzed. Objective. To analyze the developmental mechanism of hypertrophy of the Posterior Longitudinal Ligament, the authors evaluated the growth activity of cells in the Posterior Longitudinal Ligament tissues by examining the immunolocalization of the proliferating cell nuclear antigen. of Background Data. Although a number of cases of hypertrophy of the Posterior Longitudinal Ligament have been reported, the pathophysiology of Ligament hypertrophy is still unclear. It is well established that the proliferating cell nuclear antigen is a cell proliferation marker, and immunohistochemicai analysis using an anti-proliferating cell nuclear antigen antibody is of value in assessing the cell growth activity of several tissues. Methods. During anterior decompression surgery in the cervical spine, the authors extirpated Posterior Longitudinal Ligament tissues in one piece from patients with hypertrophy of the Posterior Longitudinal Ligament, ossification of the Posterior Longitudinal Ligament, cervical disc herniation, and cervical spondylotic myeiopathy. Midsagittal sections of the specimens were stained with an antibody against the proliferating cell nuclear antigen. Results. in cases of hypertrophy of the Posterior Longitudinal Ligament, immunostaining with the proliferating cell nuclear antigen was detected in cells in the Posterior Longitudinal Ligament, not only at the vertebral endplate level, but also at the midvertebral level. A similar distribution of proliferating cell nuclear antigen-positive cells was observed in cases of ossification of the Posterior Longitudinal Ligament. In cases of cervical disc herniation, however, proliferating cell nuclear antigen-positive cells in Posterior Longitudinal Ligament tissues were restricted to the vertebral endplate level. No immunostaining with the proliferating cell nuclear antigen was seen in Posterior Longitudinal Ligament tissues in cases of cervical spondylotic myelopathy. Conclusions. Cell growth activity was accelerated in Posterior Longitudinal Ligament tissues in cases of hypertrophy of the Posterior Longitudinal Ligament; such an unusual phenotype of Posterior Longitudinal Ligament cells was also expressed In cases of ossification of the Posterior Longitudinal Ligament, but not in cases of cervical disc herniation and cervical spondylotic myelopathy. Therefore, up-regulation of the growth of Posterior Longitudinal Ligament cells may contribute to the development of hypertrophy of the Posterior Longitudinal Ligament, and some common regulatory mechanism(s) on the proliferation of Posterior Longitudinal Ligament cells seem to underlie the development of hypertrophy of the Posterior Longitudinal Ligament and ossification of the Posterior Longitudinal Ligament.
Sumio Goto - One of the best experts on this subject based on the ideXlab platform.
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Proliferating Cell Nuclear Antigen in Hypertrophied Spinal Ligaments: Immunohistochemical Localization of Proliferating Cell Nuclear Antigen in Hypertrophied Posterior Longitudinal Ligament of the Cervical Spine
Spine, 1998Co-Authors: Hiroyuki Motegi, Sumio Goto, Masashi Yamazaki, Atsuo Mikata, Hideshige MoriyaAbstract:Study Design. An experimental immunohistochemical investigation using an antibody for proliferating cell nuclear antigen. Surgically-extirpated specimens of Posterior Longitudinal Ligament tissues from patients with hypertrophy of the Posterior Longitudinal Ligament and other disorders of the cervical spine were analyzed. Objective. To analyze the developmental mechanism of hypertrophy of the Posterior Longitudinal Ligament, the authors evaluated the growth activity of cells in the Posterior Longitudinal Ligament tissues by examining the immunolocalization of the proliferating cell nuclear antigen. of Background Data. Although a number of cases of hypertrophy of the Posterior Longitudinal Ligament have been reported, the pathophysiology of Ligament hypertrophy is still unclear. It is well established that the proliferating cell nuclear antigen is a cell proliferation marker, and immunohistochemicai analysis using an anti-proliferating cell nuclear antigen antibody is of value in assessing the cell growth activity of several tissues. Methods. During anterior decompression surgery in the cervical spine, the authors extirpated Posterior Longitudinal Ligament tissues in one piece from patients with hypertrophy of the Posterior Longitudinal Ligament, ossification of the Posterior Longitudinal Ligament, cervical disc herniation, and cervical spondylotic myeiopathy. Midsagittal sections of the specimens were stained with an antibody against the proliferating cell nuclear antigen. Results. in cases of hypertrophy of the Posterior Longitudinal Ligament, immunostaining with the proliferating cell nuclear antigen was detected in cells in the Posterior Longitudinal Ligament, not only at the vertebral endplate level, but also at the midvertebral level. A similar distribution of proliferating cell nuclear antigen-positive cells was observed in cases of ossification of the Posterior Longitudinal Ligament. In cases of cervical disc herniation, however, proliferating cell nuclear antigen-positive cells in Posterior Longitudinal Ligament tissues were restricted to the vertebral endplate level. No immunostaining with the proliferating cell nuclear antigen was seen in Posterior Longitudinal Ligament tissues in cases of cervical spondylotic myelopathy. Conclusions. Cell growth activity was accelerated in Posterior Longitudinal Ligament tissues in cases of hypertrophy of the Posterior Longitudinal Ligament; such an unusual phenotype of Posterior Longitudinal Ligament cells was also expressed In cases of ossification of the Posterior Longitudinal Ligament, but not in cases of cervical disc herniation and cervical spondylotic myelopathy. Therefore, up-regulation of the growth of Posterior Longitudinal Ligament cells may contribute to the development of hypertrophy of the Posterior Longitudinal Ligament, and some common regulatory mechanism(s) on the proliferation of Posterior Longitudinal Ligament cells seem to underlie the development of hypertrophy of the Posterior Longitudinal Ligament and ossification of the Posterior Longitudinal Ligament.
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Long-term follow-up evaluation of surgery for ossification of the Posterior Longitudinal Ligament.
Spine, 1995Co-Authors: Sumio Goto, Tsuneji KitaAbstract:Study Design. We compared anterior and Posterior surgery for cervical myelopathy resulting from ossification of the Posterior Longitudinal Ligament. Surgical techniques, based on shape and distribution of ossification of the Posterior Longitudinal Ligament, were divided into four technical phases. Objectives. Long-term follow-up data on anterior and Posterior surgery were analyzed to establish guidelines for surgical treatment. Summary of Background Data. Comparison of anterior and Posterior surgery is difficult because surgical techniques, ossification of the Posterior Longitudinal Ligament shape classifications, and surgical criteria varied. No reports have accurately assessed spinal changes over a 10-year follow-up period. Methods. Fifty patients received anterior surgery and 65 received Posterior surgery between 1968 and 1993. Assessment after surgery was based on the recovery rate using the scoring system of the Japanese Orthopaedic Association. Spinal changes in the anterior group were assessed radiographically. Results. Recovery and final results improved with phase after anterior, but not Posterior, surgery. Neurologic deterioration after initial recovery was lower for the anterior group. One third of patients in the anterior group followed for more than 7 years exhibited neurologic deterioration, with most showing these changes within 10 years. Worsening was attributed to insufficient removal of lateral, superior, or inferior ossification of the Posterior Longitudinal Ligament, reossification at the excision site, kyphotic malalignment, growth of ossification at upper cervical levels, or untreated complicated hypertrophy of the Posterior Longitudinal Ligament. Many patients showed a good outcome after surgery. Accurate alignment and long-range fusion improved results. the cord was compressed in a canal narrowed to under 3 mm, anterior surgery was considered too risky. Conclusions. Complete extirpation of ossification of the Posterior Longitudinal Ligament as confirmed by ultrasonography during surgery and long-range fusion with fibular grafts is advocated in the management of ossification of the Posterior Longitudinal Ligament.
Shunji Matsunaga - One of the best experts on this subject based on the ideXlab platform.
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Natural History of Ossification of the Posterior Longitudinal Ligament (OPLL)
OPLL, 2020Co-Authors: Shunji MatsunagaAbstract:Ossification of the Posterior Longitudinal Ligament (OPLL) is an important disease-causing spinal cord symptom. The timing of surgery and indication of preventive surgery have yet to be concluded. The main cause is the lack of research on the natural history of the onset of spinal cord symptoms of this disease. The author will introduce the research results of the single- and the multicenter facilities that have been conducted on the natural history of the clinical symptoms of OPLL and also mention the predictive factors of the onset of neurological symptoms in this disease. The Kaplan–Meier estimate of myelopathy-free survival among patients without myelopathy at the first visit was 71% at 30 years follow-up. The author examined the risk factor for the development of myelopathy in patients with asymptomatic ossification of the Posterior Longitudinal Ligament by a multicenter prospective study. On univariate and multivariate logistic regression analysis, the development of myelopathy was significantly associated with spinal canal stenosis ratio, large range of motion of the cervical spine, and lateral-deviated type OPLL. The knowledge of natural history of this disease is essential for the treatment of this disease and further research in All Japan is desired in the future.
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Conservative Treatment of Ossification of the Posterior Longitudinal Ligament
OPLL, 1997Co-Authors: Eiji Taketomi, Takashi Sakou, Shunji MatsunagaAbstract:We present here conservative treatment for patients with cervical ossification of the Posterior Longitudinal Ligament (OPLL) when they have local symptoms such as neck pain, pain and numbness of upper extremities without myelopathy. We sometimes conservatively treat patients with even slight myelopathy. We usally do cervical traction and cervical orthoses as conservative treatment to retain other local cervical conditions. Few studies, however, have been published about the effects of conservative treatment [1–3].
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Orthotopic ossification of the spinal Ligaments of Zucker fatty rats : a possible animal model for ossification of the human Posterior Longitudinal Ligament
Journal of orthopaedic research : official publication of the Orthopaedic Research Society, 1997Co-Authors: Toshihiro Okano, Shunji Matsunaga, Yasuhiro Ishidou, Mitsuyasu Kato, Takeshi Imamura, Koji Yonemori, Nobuo Origuchi, Hiroki Yoshida, Peter Ten Dijke, Takashi SakouAbstract:Ossification of the Posterior Longitudinal Ligament is a human genetic disease in which pathological ectopic ossification of the spinal Ligaments develops. This leads to myelopathy or radiculopathy due to compression of the spinal cord. In this study, we investigated the histological features of orthotopic ossification of the spinal Ligaments of senile Zucker fatty rats. A remarkably high incidence of orthotopic ossification was observed mainly in the thoracic spinal Ligaments as compared with controls. The histopathological findings were similar to those for ossification of the human Posterior Longitudinal Ligament. Bone morphogenetic proteins and activins, which exert their effects by way of specific type-I and type-II serine/threonine kinase receptors, play important roles in the formation of bone and cartilage. In the spinal Ligaments of Zucker fatty rats, bone morphogenetic protein receptors and activin receptors were immunohistochemically detected around the ossified foci in a manner similar to that previously shown for the ossified tissue from patients who had ossification of the Posterior Longitudinal Ligament. Thus, bone morphogenetic proteins and activin receptors might play important roles in orthotopic ossification of the spinal Ligaments of Zucker fatty rats as well as in ossification of the Posterior Longitudinal Ligament of humans. In addition, bone morphogenetic protein-receptor-IA was expressed in the nonossified Ligament, suggesting that the spinal Ligaments, of the rats may have a predisposition to orthotopic ossification. In the controls, no expression of bone morphogenetic protein receptors or of activin receptors was observed. In conclusion, there is a great degree of similarity between orthotopic ossification of the spinal Ligaments of Zucker fatty rats and ossification of the Posterior Longitudinal Ligament of humans. Thus, the rats provide a useful animal model for the study of ossification of the human Posterior Longitudinal Ligament.
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Epidemiology of Ossification of the Posterior Longitudinal Ligament
OPLL, 1997Co-Authors: Shunji Matsunaga, Takashi SakouAbstract:Ossification of the Posterior Longitudinal Ligament (OPLL) is an intractable disease that causes severe myelopathy and radiculopathy. The report of an autopsy case made by Tsukimoto in 1960 [1] led to the establishment of this disease as an entity. The Investigation Committee on Ossification of the Spinal Ligaments was organized by the Japanese Ministry of Public Health and Welfare in 1975. Research to elucidate this disease has continued since then.
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Genetic study of ossification of the Posterior Longitudinal Ligament in the cervical spine with human leukocyte antigen haplotype.
Spine, 1991Co-Authors: Takashi Sakou, Shunji Matsunaga, Eiji Taketomi, Masao Yamaguchi, S. Sonoda, Shinji YashikiAbstract:To evaluate the genetic background of ossification of the Posterior Longitudinal Ligament, the relationship between the presence of absence of ossification and human leukocyte antigen haplotypes was studied in 33 families of patients with ossification of the Posterior Longitudinal Ligament. The study revealed that human leukocyte antigen haplotypes formed certain types of clusters, and that some human leukocyte antigen haplotypes were very rare in the Japanese population, suggesting the involvement of human leukocyte antigen-linked factors in the pathogenesis of ossification of the Posterior Longitudinal Ligament of the cervical spine. In the families of these patients, ossification of the Posterior Longitudinal Ligament was demonstrated by radiography in 56% (10/18) of the siblings. Each of these siblings shared both human leukocyte antigen haplotypes with the patient. None of those who shared only one human leukocyte antigen haplotype with the patient had developed ossification of the Posterior Longitudinal Ligament. From these findings, the presence of both pathogenic human leukocyte antigen haplotypes is considered to be necessary for the development of ossification of the Posterior Longitudinal Ligament, and this genetic predisposition may be activated by multiple factors, including regressive degeneration due to aging and the environment.
Nancy E. Epstein - One of the best experts on this subject based on the ideXlab platform.
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In vitro characteristics of cultured Posterior Longitudinal Ligament tissue.
Spine, 2002Co-Authors: Nancy E. Epstein, Daniel A. Grande, Arnold S. BreitbartAbstract:To determine the osteogenicity of Posterior Longitudinal Ligament ossification, the Posterior Longitudinal Ligament obtained during anterior cervical surgery from patients with the disorder was analyzed with in vitro cultures. To determine the osteogenicity of the Posterior Longitudinal Ligament. The osteogenicity of Posterior Longitudinal Ligament ossification in North America requires better documentation. The Posterior Longitudinal Ligament obtained during anterior cervical corpectomy with fusion from seven patients, three with ossification of the Posterior Longitudinal Ligament documented by magnetic resonance imaging and computed tomography and four with spondylosis, was blindly submitted for in vitro culture. Explants of the Posterior Longitudinal Ligament were placed in Dulbecco modified Eagle medium with 10% fetal calf serum, antibiotics, 4 mmol/L x L-proline, and 50 mg/L ascorbic acid. After reaching confluency, cells were trypsinized, and first-passage cells were used for all osteocalcin measurements to establish their osteoblastic phenotype. Periosteal cells, previously shown to synthesize osteocalcin, were used as a positive control. The cells were incubated with 1,25(OH)2 vitamin D3 at 10E-8 M for 72 hours in serum-free medium. The supernatants were collected and frozen, after which the quantity of osteocalcin induced by exposure to 1,25(OH)2 vitamin D3 was determined using enzyme-linked immunoassay. Control replicate cultures were measured without incubation using vitamin D3. Ossification of the Posterior Longitudinal Ligament cell lines responded positively with osteocalcin synthesis in the 0.1 to 0.4 ng/M range. The cell line of the patient with spondylosis alone did not respond to vitamin D3 priming. Posterior Longitudinal Ligament cells from the three North American white patients with ossification of the Posterior Longitudinal Ligament, when cultured in vitro, synthesized osteocalcin on vitamin D3 priming, confirming their osteoblastic phenotype, whereas Posterior Longitudinal Ligament cells from four white patients with isolated spondylosis did not.
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In vitro characteristics of cultured Posterior Longitudinal Ligament tissue.
Spine, 2002Co-Authors: Nancy E. Epstein, Daniel A. Grande, Arnold S. BreitbartAbstract:Study Design. To determine the osteogenicity of Posterior Longitudinal Ligament ossification, the Posterior Longitudinal Ligament obtained during anterior cervical surgery from patients with the disorder was analyzed with in vitro cultures. Objectives. To determine the osteogenicity of the Posterior Longitudinal Ligament. Summary of Background Data. The ostogenicity of Posterior Longitudinal Ligament ossification in North America requires better documentation. Methods. The Posterior Longitudinal Ligament obtained during anterior cervical corpectomy with fusion from seven patients, three with ossification of the Posterior Longitudinal Ligament documented by magnetic resonance imaging and computed tomography and four with spondylosis, was blindly submitted for in vitro culture. Explants of the Posterior Longitudinal Ligament were placed in Dulbecco modified Eagle medium with 10% fatal calf serum, antibiotics, 4 mmol/L L proline and 50 mg/L ascorbic acid. After reaching confluency, calls were trypsinized, and first-passage cells were used for all osteocalcin measurements to establish their osteoblastic phenotype. Periosteal cells, previously shown to synthesize osteoblastic, were used as a positive control. The cells were incubated with 1,25(OH) 2 vitamin D3 at 10E-8 M for 72 hours in serum-free medium. The supernatants were collected and frozen, after which the quantity of osteocalcin induced by exposure to 1,25(OH) 2 vitamin D3 was determined using enzyme-linked immunoassay. Control replicate cultures were measured without incubation using vitamin D3. Results .Ossification of the Posterior Longitudinal Ligament cell lines responded positively with osteocalcin synthesis in the 0.1 to 0.4 ng/M range. The cell line of the patient with spondylosis alone did not respond to vitamin D3 priming. Conclusions. Posterior Longitudinal Ligament cells from the three North American white patients with ossification of the Posterior Longitudinal Ligament, when cultured in vitro, synthesized osteocalcin on vitamin D3 priming, confirming their osteoblastic phenotype, whereas Posterior Longitudinal Ligament cell from four white patients with isolated spondylosis did not.
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Ossification of the Posterior Longitudinal Ligament in Evolution
OPLL, 1997Co-Authors: Nancy E. EpsteinAbstract:Classical ossification of the Posterior Longitudinal Ligament (OPLL) may be seen in 27% of Japanese and 25% of North American populations with myelopathy [1–3]. However, an additional subset of patients with a less mature form of OPLL has now been identified [4], Of 90 patients evaluated in our own OPLL series, 40 had classical OPLL, but 50 demonstrated an earlier variant of OPLL that appeared to be part of an evolving continuum toward classical OPLL [5]. This earlier form of OPLL was termed OPLL in evolution (OEV). These individuals, typically in their mid-forties rather than their late fifties, exhibit less significant spinal cord but more prominent nerve root compression. OEV appears on computed tomography-(CT-) based examinations to be composed of hypertrophied Posterior Longitudinal Ligament (PLL), centered at the disk space but extending toward midvertebral body levels across single or multiple segments, with punctate, immature pearls of cartilage-calcification-ossification. Although CT and myelo-CT studies best distinguish OEV from classical OPLL, differentiation from disk disease and spondylosis, particularly using magnetic resonance imaging (MRI) alone, is more difficult.
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The surgical management of ossification of the Posterior Longitudinal Ligament in 51 patients.
Journal of spinal disorders, 1993Co-Authors: Nancy E. EpsteinAbstract:Summary:Ossification of the Posterior Longitudinal Ligament (OPLL) in the cervical spine warrants unique clinical, radiographic, and surgical management. OPLL patients presenting with severe myelopathy require full assessment with both magnetic resonance imaging (MRI) and computed tomography-based (
