Posterior decompression and fusion versus laminoplasty for cervical ossification of posterior longitudinal ligament: a systematic review and meta-analysis.

Both posterior decompression and fusion (PDF) and laminoplasty (LAMP) have been used to treat cervical myelopathy due to multilevel ossification of posterior longitudinal ligament (OPLL). However, considerable controversy exists over the choice of the two surgical strategies. Thus, the aim of this study is to compare clinical outcomes of PDF and LAMP for treatment of cervical myelopathy due to multilevel OPLL. We searched PubMed, EMBASE and Cochrane Central Register of Controlled Trials database to identify relevant clinical studies compared with clinical outcomes of PDF and LAMP for cervical OPLL. The primary outcomes including Japanese Orthopaedic Association (JOA) score and recovery rate of JOA were evaluated, and the secondary outcomes involving visual analogue scale (VAS), cervical curvature, OPLL progression rate, complication rate, reoperation rate and surgical trauma were also evaluated using Stata software. A total of nine studies were included in the current study, involving 324 patients. The current study suggests that compared with LAMP, PDF achieves a lower OPLL progression rate, better postoperative cervical curvature and similar neurological improvement in the treatment of multilevel cervical OPLL. However, PDF has a higher complication rate, more surgical trauma and higher postoperative VAS than LAMP.

Serum oxidative stress influences neurological recovery after surgery to treat acutely worsening symptoms of compression myelopathy: a cross-sectional human study.

BACKGROUND: Recent reports indicate that oxidative stress induced by reactive oxygen species is associated with the pathobiology of neurodegenerative disorders that involve neuronal cell apoptosis. Here we conducted a cross-sectional study to evaluate serum levels of oxidative stress in cervical compression myelopathy. METHODS: Thirty-six serum samples were collected preoperatively from patients treated for acutely worsening compression myelopathy (AM) and chronic compression myelopathy (CM). Serum levels of oxidative stress markers were evaluated by measuring derivatives of reactive oxygen metabolites (ROM), which reflect concentrations of hydroperoxides. ROM in healthy individuals range from 250 to 300 (U. CARR), whereas ROM >340-400 and > 400 define moderate and severe levels of oxidative stress, respectively. Difference of ROM by the cause of disorders whether cervical spondylotic myelopathy (CSM) or cervical ossification of longitudinal ligament (OPLL), correlations between ROM and patient age, body mass index (BMI), history of smoking, existence of diabetes were examined. Neurological evaluations according to Japanese Orthopaedic Association (JOA) scores were performed and correlated with ROM. RESULTS: ROM increased to 349.5 ± 54.8, representing a moderate oxidative stress, in CM samples. ROM increased to 409.2 ± 77.9 in AM samples, reflecting severe oxidative stress which were significantly higher than for CM samples (p < 0.05). There was no significant difference by the cause of disorders (CSM or OPLL). ROM were significantly increased in AM serum samples from female patients versus AM male and CM patients (p < 0.05). There were no correlations between ROM and age, BMI, history of smoking, and existence of diabetes. A negative correlation between ROM and recovery rate of JOA score (R2 = 0.454, p = 0.047) was observed in the AM group. CONCLUSIONS: Although moderate oxidative stress was present in patients with CM, levels of oxidative stress increased in severity in patients with AM. These results suggest that postsurgical neurological recovery is influenced by severe oxidative stress in AM.

Concomitant Fahr's syndrome and thoracic ossification of the posterior longitudinal ligament caused by idiopathic hypoparathyroidism - case report.

BACKGROUND: Fahr's syndrome presenting multiple and symmetric calcification of basal ganglia and cerebral cortex is rare, and idiopathic hypoparatyroidism is known as one of the causes. The relationship between ossification of posterior longitudinal ligament (OPLL) and idiopathic hypoparatyroidism is also reported in a few cases. Here, we report a patient presenting concomitant Fahr's syndrome and thoracic OPLL developed by idiopathic hypoparatyroidism. CASE PRESENTATION: 53-year-old female patient presented myelopathic sign including gait disturbance and both leg weakness (Grade 3) for 4 months after slip down, and has the history of anti-epileptic medication for several years. Magnetic resonance imaging revealed cord compression by the mixed-type OPLL from T5 to T9, and decompressive surgery was planned. Sudden onset generalized tonic-clonic seizure attack developed before the surgery. Hypocalcemia (3.7 mg/dL) with QT prolongation on electrocardiogram, hypomagnesemia (1.4 mg/dL), hyperphosphatemia (7.7 mg/dL), hypoparathyroidism, and normal range of vitamin D was noted. Brain study showed Fahr's syndrome with multiple and symmetric calcification of basal ganglia, cerebral cortex, and cerebellum. Decompressive laminectomy was performed after transient correction of hypocalcemia. The myelopathic symptoms improved to normal walking by the 14-month follow-up. The cause of hypoparathyroidism was concluded to be idiopathic. CONCLUSION: Concomitant expression of Fahr's syndrome and OPLL related with idiopathic hypoparatyroidism is very rare. However, we recommend considering the possibility of hypoparathyroidism and Fahr's syndrome when we evaluate the patients with OPLL to avoid the risks of sudden onset seizure and cardiac arrhythmia due to cerebral lesions and hypocalcemia.

Epidemiology of ossification of the spinal ligaments and associated factors in the Chinese population: a cross-sectional study of 2000 consecutive individuals.

BACKGROUND: The epidemiology and cause of ossification of the spinal ligaments (OSL) remains obscure. To date, there is no study that comprehensively evaluates the prevalence, distribution, and concomitance of each type of OSL by CT among general Chinese population. We therefore aimed to comprehensively investigate epidemiological characteristics of OSL using whole spine CT in the Chinese population and examine the factors that correlate with the presence of OSL. METHODS: Ossification of the posterior longitudinal ligament (OPLL), ligamentum flavum (OLF), anterior longitudinal ligament (OALL), nuchal ligament (ONL), and diffuse idiopathic skeletal hyperostosis (DISH) were evaluated from the subjects who underwent PET/CT for the purpose of cancer screening in our hospital. Prevalence, distribution, and concomitance of OSL were reviewed. Logistic regression analysis was performed to identify the risk factors of OSL. RESULTS: A total of 2000 subjects (1335 men and 665 women) were included. The prevalence rate of cervical OPLL (C-OPLL) was 4.1%, thoracic OPLL (T-OPLL) 2.25%, lumbar OPLL (L-OPLL) 0.8%, thoracic OLF (T-OLF) 37.65%, lumbar OLF (L-OLF) 1.45%, ONL 31.5%, DISH 3.85%. The most commonly involved level was C5 for C-OPLL, T1 for T-OPLL, T10 for T-OLF, and T8/9 for OALL. 21% of subjects with C-OPLL had T-OPLL, 44% of C-OPLL had T-OLF, 38% of T-OPLL had C-OPLL, 53% of T-OPLL had T-OLF, 44% of L-OPLL had T-OPLL, and 56% of L-OPLL had T-OLF. The average age of OSL-positive subjects was significantly higher than that of OSL-negative subjects. The results of the multiple regression analysis revealed that males had a strong association with DISH (odds ratio, 3.15; 95% confidence interval, 1.27-7.78; P = 0.013). CONCLUSION: The prevalence of OSL in the Chinese was revealed. Tandem ossification is not uncommon in people with OSL. There is a high incidence of multiple-regional OPLL in the whole spine. Approximately half of the subjects with OPLL coexist with T-OLF. For patients with clinical symptoms induced by OPLL, thorough evaluation of whole spine using CT is recommended.

Co-existence of ossification of the nuchal ligament is associated with severity of ossification in the whole spine in patients with cervical ossification of the posterior longitudinal ligament -A multi-center CT study.

BACKGROUND: Previous studies have shown that patients with cervical ossification of the posterior longitudinal ligament (OPLL) often have co-existing ossification of the nuchal ligament (ONL). However, no studies have focused on ONL and its relevance to the severity of OPLL or ossification of other spinal ligaments, such as anterior longitudinal ligament (OALL), ligamentum flavum (OLF), and supraspinous/interspinous ligament (OSIL). METHODS: In this multicenter study, we investigated ossification of the spinal ligaments in the whole spine computed tomography (CT) images of 233 cervical OPLL patients. The severity of ossification was evaluated using ossification index for each spinal ligament, calculated as the sum of the level of ossification. We compared the severity of ossification in each spinal ligament between patients with ONL and those without ONL. Furthermore, we investigated how the number of segments, where ONL exists, affects the severity of ossification in each spinal ligament. RESULTS: One hundred thirty patients (55.8%) had co-existing ONL in the cervical OPLL patients included in this study. The ONL (+) group included more male and aged patients. The cervical ossification indexes of OPLL and OALL were higher in ONL (+) patients than in ONL (-) patients. The thoracolumbar ossification indexes of OALL and OSIL were also higher in ONL (+) patients. Logistic regression analysis revealed that age, gender and cervical OA-index were independent factors correlating to the existence of ONL. In the cervical spine, both the ossification indexes of OALL and OPLL increased as the levels of ONL increased. Similarly, in the thoracolumbar spine, both the ossification indexes of OALL and OSIL were increased as the levels of cervical ONL increased. In the multiple regression analysis, cervical OA-index and thoracolumbar OSI-index showed significant correlation with the number of ONL levels. CONCLUSIONS: Co-existence of ONL in cervical OPLL patients was associated with the severity of spinal hyperostosis especially in cervical OPLL, OALL, thoracolumbar OALL and OSIL.

Ossification of the posterior longitudinal ligament in the cervical spine: a review.

Ossification of the posterior longitudinal ligament (OPLL) is a rare pathologic process of lamellar bone deposition that can result in spinal cord compression. While multiple genetic and environmental factors have been related to the development of OPLL, the pathophysiology remains poorly understood. Asymptomatic patients may be managed conservatively and patients with radiculopathy or myelopathy should be considered for surgical decompression. Multiple studies have demonstrated the morphology and size of the OPLL as well as the cervical alignment have significant implications for the appropriate surgical approach and technique. In this review, we aim to address all the available literature on the etiology, history, presentation, and management of OPLL in an effort to better understand OPLL and give our recommendations for the treatment of patients presenting with OPLL.

Patient satisfaction with double-door laminoplasty for cervical compression myelopathy.

BACKGROUND: Patient satisfaction with posterior laminoplasty for cervical compression myelopathy is not yet established. Moreover, postoperative patient-reported outcomes (PROs) associated with patient satisfaction remain unclear. This study aimed to investigate patient satisfaction after double-door laminoplasty for cervical compression myelopathy, and to identify the postoperative patient-reported outcomes associated with patient satisfaction. METHODS: This retrospective study included 97 patients with cervical compression myelopathy who underwent double-door laminoplasty between 2002 and 2010 in our institution [mean follow-up: 58 months (range 12-123 months)]. We assessed postoperative PROs from questionnaires administered before surgery and at the latest follow-up. These questionnaires included the Neck Disability Index, physical and mental component summary of Short Form-36, EuroQol-5 dimension, Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and a numerical rating scale of pain or numbness in the neck, arms, and scapular lesion. Satisfaction was evaluated on the basis of a seven-point scale. Patients were divided into two groups: satisfied (very satisfied, satisfied, slightly satisfied) and dissatisfied (neither satisfied nor dissatisfied, slightly dissatisfied, dissatisfied, very dissatisfied). All PROs and the effectiveness of surgical treatment assessed by JOACMEQ were compared between both groups. RESULTS: The satisfied group comprised 69 patients (71 %). Univariate analysis revealed a significant difference in scapular pain, Neck Disability Index, physical component summary of Short Form-36, postoperative mental component summary of Short Form-36, and improvement of lower extremity function postoperatively between both groups. Multivariate analysis revealed that there was a significantly higher proportion of patients with improved lower extremity function in the satisfied group than in the dissatisfied group. CONCLUSIONS: In conclusion, 71 % of the patients who underwent double-door laminoplasty for cervical compression myelopathy were satisfied. The findings of this study, which examines the association between patient satisfaction and PROs, suggest that improvement in lower extremity function following surgical intervention affects patient satisfaction in those with cervical compression myelopathy.

[Ossification of the Posterior Longitudinal Ligament Found in a Case of Sudden Head-tilt Difficulty following Induction of General Anesthesia].

We report a case of sudden head-tilt difficulty after induction of general anesthesia which was postoperatively diagnosed as ossification of the posterior longitudinal ligament. A 42-year-old man weighing 115 kg was scheduled for emergent laparoscopic appendectomy for acute appendicitis. Prior to induction of anesthesia, the patient could tilt his head, but was unable to do so afterwards. Following mask ventilation with jaw-thrust maneuver, we successfully performed tracheal intubation using the Pentax-AWS Airwayscope. After surgery, he was diagnosed with ossification of the posterior longitudinal ligament by an orthopedist.

Resection of spinous processes can cause spinal cord injury in patient with ossification of the posterior longitudinal ligament in the thoracic spine.

STUDY DESIGN: Case report. OBJECTIVE: To report intraoperative spinal cord injury by resection of spinous processes in a 73-year-old man with ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine. METHODS: A 73-year-old man presented with cervicothoracic OPLL with bilateral numbness and clumsiness of his hand, weakness of his lower extremities and severe gait disturbance. His Japanese Orthopaedic Association (JOA) score was 7.5 out of 17. Cervical laminoplasty (C2-6), cervicothoracic laminectomy (C7-T10) and posterior fusion (C7-T10) were performed in the prone position with electrophysiologic monitoring of the spinal cord-evoked potentials (SCEPs). RESULTS: The spinal processes with supra- and interspinous ligaments between C7 and T10 were resected. After resection, the amplitude of SCEP waveforms decreased rapidly to <10% of control levels. Laminectomy was performed, and, after 80 min of SCEP deterioration, an instrumented fusion with correction for kyphosis was completed. The SCEP amplitude recovered gradually. Immediately after surgery, the patient suffered severe motor loss in both lower limbs. His neurological recovery progressed gradually from 2 days after surgery, and he was able to walk at 3 months after surgery. At 6 years after surgery, the JOA score was 11. CONCLUSION: Our results suggest that intraoperative spinal cord injury can occur before posterior decompression by resection of spinal processes with supra- and interspinous ligaments. The timing of the instrumented stabilization using a temporary rod is important and should be considered immediately after posterior exposure of the spine.

[Ossification of the posterior longitudinal ligament (OPLL) and the ligamentum flavum (OLF)].

The adult population is frequently sustained with ossification of the posterior longitudinal ligament (OPLL) and/or the ligamentum flavum (OLF) of the spine and the diseases may subsequently result is serious spinal cord insult with profound paralysis of the extremities. These pathologies are genetically denoted metaplasia of the elastic fibers of the ligament with consequent ectopic ossification process. The spinal cord is chronically compressed and will result in profound motor paralysis with sensory deficit. Both diseases are well imaged on CT and MRI, showing a various magnitude of spinal cord compression.

Plasma pentosidine concentration is associated with ligament ossification and high-grade osteoarthritis: The ROAD study.

AIM: No studies have examined the association between plasma pentosidine levels and ossification diseases in large cohorts of Japanese residents. This study aimed to investigate the association between cervical ossification of the posterior longitudinal ligament (OPLL) and other ossification diseases, including diffuse idiopathic skeletal hyperostosis, lumbar spondylosis and knee osteoarthritis (OA), by examining plain radiographs of the knee, and cervical, thoracic and lumbar spine from 1690 participants, and the association between these diseases and plasma pentosidine. DESIGN: We enrolled 1690 participants (596 men and 1094 women) from mountainous and coastal areas from the study population of the previous Research on Osteoarthritis/Osteoporosis Against Disability study. X-ray examination of the cervical/thoracic/lumbar spine and knee was carried out only in these individuals, and not those from urban areas. Plasma pentosidine concentrations were determined using enzyme-linked immunoassays. RESULTS: Radiographic OPLL was detected in 30 (17 men, 13 women) of 1562 individuals who underwent X-ray examination of the cervical spine. OPLL, diffuse idiopathic skeletal hyperostosis, lumbar spondylosis Kellgren-Lawrence (KL) grade, and knee OA KL grade were associated with high plasma pentosidine concentrations (all P < 0.05). Furthermore, significant intragroup differences (KL grade 4 vs 3) of plasma pentosidine concentration were observed between the lumbar spondylosis and knee OA groups. The plasma pentosidine concentration was significantly associated with age, OPLL, lumbar spondylosis (KL grade 4) and knee OA (KL grade 4). CONCLUSIONS: OPLL is significantly associated with other ossification diseases. The development of more severe OA might lead to the accumulation of plasma pentosidine. Plasma pentosidine levels were associated with OPLL and severe OA. Geriatr Gerontol Int 2024; 24: 154-160.

Increased bone mineral density and decreased prevalence of osteoporosis in cervical ossification of the posterior longitudinal ligament: a case-control study.

Bone and mineral metabolism has been reported to affect the development of the ossification of the posterior longitudinal ligament (OPLL). The aim of this study was to compare bone mineral densities (BMD) and rate of osteoporosis between cervical OPLL and a matched control group. We also investigated the correlation of BMD with the number of cervical spine levels involved with OPLL. From 1999 to August 2011, 178 patients with cervical OPLL underwent dual-energy X-ray absorptiometry (DXA) at our institute. The control group was age-, sex-, and body mass index (BMI)-matched with the OPLL group on a 1:1 basis. BMD was measured at the lumbar spine (L1-L4), femoral neck, and total femur using DXA. Age, sex, and BMI were the same in the OPLL and control groups. BMDs of the OPLL and control groups were significantly different in the lumbar spine, femoral neck, and total femur (p = 0.0001, 0.0001, 0.009, respectively). Rates of osteopenia and osteoporosis were lower in the OPLL than in the control group according to lumbar spine and femoral neck DXA (p = 0.01, 0.03, respectively). A positive correlation was observed between lumbar spine BMD and the number of cervical spine levels involved with OPLL (p = 0.004).

Interobserver and intraobserver reliability of the classification and diagnosis for ossification of the posterior longitudinal ligament of the cervical spine.

PURPOSE: Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine has been classified into four types by lateral plain radiographs, but the reliability of the classification and of the diagnosis of either cervical OPLL or cervical spondylotic myelopathy (CSM) was unknown. We investigated the interobserver and intraobserver reliability of the classification and diagnosis for OPLL by radiographs and computed tomography (CT) images. METHODS: A total of 16 observers classified each patient's images into five groups; OPLL continuous, segmental, mixed, circumscribed type, or CSM. To evaluate interobserver reliability, the observers first classified only radiograph images, and next both radiographs and CT images. On another day they followed the same procedure to evaluate intraobserver reliability. We also evaluated interobserver and intraobserver reliability of the diagnosis of either cervical OPLL or CSM. RESULTS: Interobserver reliability of the classification with radiographs only showed moderate agreement, but interobserver reliability with both radiographs and CT images showed substantial agreement. Intraobserver of reliability the classification was also improved by additional CT images. Interobserver reliability of the diagnosis with both radiographs and CT images was almost similar to with radiographs only. Intraobserver reliability of the diagnosis was improved by additional CT images. CONCLUSIONS: This study suggested that the reliability of the classification and diagnosis for cervical OPLL was improved by additional CT images. We propose that diagnostic criteria for OPLL include both radiographs and CT images.

Surgical technique: Hemilaminectomy and unilateral lateral mass fixation for cervical ossification of the posterior longitudinal ligament.

BACKGROUND: Surgical approaches for cervical ossification of the posterior longitudinal ligament (OPLL) include anterior, posterior, or combined decompression with or without fusion. The goal of surgery is to decompress the spinal cord while maintaining the stability and sagittal alignment of the cervical spine. C5 palsy has been reported as a postoperative complication of cervical laminectomy or laminoplasty characterized as motor weakness of the muscles supplied with C5 nerve roots. Several studies have shown this phenomenon was partially attributable to posterior shift of spinal cord. DESCRIPTION OF TECHNIQUE: The rationale for choosing hemilaminectomy is to control postoperative posterior shift of the spinal cord and afford more stability by preserving ligamentous attachments and posterior bony elements as much as possible. After a fixation system of lateral mass screws and rods is installed unilaterally, laminae are removed from the underlying dura using a high-speed burr and Kerrison laminectomy rongeur on the other side. The spinous processes are preserved. PATIENTS AND METHODS: Patients with multilevel continuous/mixed cervical OPLL are good candidates for this technique. We retrospectively reviewed 146 patients who had multilevel continuous/mixed cervical OPLL and underwent surgery from January 2006 to January 2010. Neurologic condition was evaluated using the improvement ratio (IR) of the Japanese Orthopaedic Association (JOA) score for cervical myelopathy. RESULTS: The mean JOA score increased from 10 points before surgery to 14 points at last followup. The mean IR of neurologic function (JOA score) was 59%. C5 palsy was not observed in any patient after decompression, and cervical lordosis changed from 8.7° preoperatively to 9.1° at last followup. CONCLUSIONS: For patients with multilevel continuous/mixed cervical OPLL without fixed kyphosis, multilevel hemilaminectomy with unilateral lateral mass fixation is an effective alternative technique. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

A case of psoriasis vulgaris with diffuse idiopathic skeletal hyperostosis involved with ossifications of posterior and anterior longitudinal ligament.

Diffuse idiopathic skeletal hyperostosis (DISH) is difficult to distinguish from various forms of inflammatory arthritis, including psoriatic arthritis (PsA), rheumatoid arthritis, and ankylosing spondylitis. A 67-year-old Japanese male had been treated for psoriasis vulgaris for 13 years. Numbness of his right arm and lower limbs and spinal stiffening had developed 7 years prior to his initial evaluation at our facility. He noticed pain mainly while exercising. There were symmetrical marginal syndesmophytes in the spine, from the thoracic vertebrae to the upper lumbar vertebrae, on radiological examinations. We therefore suspected DISH. Furthermore, ossifications of the posterior and anterior longitudinal ligaments were noted in the cervical spine. Laboratory examinations revealed a normal peripheral white blood cell count, serum C-reactive protein, and erythrocyte sedimentation rate, and he was negative for rheumatoid factor. We detected human leukocyte antigen B39 but not B27. All distal interphalangeal joints were swollen but without pain. X-ray imaging showed narrowing of the joint space, and the consolidation of the joint was recognized, but there was no new juxta-articular bone formation. Based on clinical and radiological findings, we concluded that he had DISH and not PsA. DISH was indicated by marked radiological features of the axial skeleton, particularly the thoracic spine, but may also have involved the peripheral joints. DISH is one of the entheseal disorders, and 10% of Japanese middle-aged and elderly men have DISH. Therefore, the differentiation of DISH from PsA is necessary in psoriasis patients with spinal involvement.

Anterior corpectomy with fusion in combination with an anterior cervical plate in the management of ossification of the posterior longitudinal ligament.

STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of this study is to evaluate the safety and efficacy of an anterior cervical plate (ACP) used in combination with anterior corpectomy with fusion (ACF) for cervical ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: Consensus is lacking about the most suitable method to treat cervical myelopathy caused by OPLL. The decision to perform an ACF to treat multilevel myelopathy is controversial because of the potential for problems in the grafted bone. METHODS: We evaluated the surgical outcome of ACF combined with insertion of an ACP for treating cervical myelopathy caused by OPLL. The study group comprised 68 patients who were treated from 2006 to 2009 and followed for an average of 29.6 months. We retrospectively reviewed the information in the patients' charts and radiographs. RESULTS: No dislodgement of the grafted bone or implant was observed, and no patient developed infection, esophageal or tracheal lacerations, or rupture. Radiographs showed no evidence of nonunion. The mean preoperative and the final follow-up C2 to C7 lordotic angles were 6.2±9.5 degrees and 9.4±7.6 degrees, respectively. The preoperative and the final follow-up lordotic angles of the fusion area were 2.0±8.1 degrees and 5.9±6.4 degrees, respectively. The average change in fusion area length was a 1.2 mm increase from before to after the operation and a 1.8 mm decrease from after the operation to the final follow-up. The average recovery rate of the Japanese Orthopaedic Association score was 63.0%. The surgical outcome of ACF with an ACP is satisfactory. CONCLUSIONS: Insertion of an ACP is a good solution for preventing problems with the grafted bone after ACF. Our study suggests that the indications for an anterior-only procedure for the management of cervical OPLL can be expanded.

[The analysis of prognostic factors in patients with thoracic ossification of the ligamentum flavum and thoracic ossification of posterior longitudinal ligament by posterior decompression].

OBJECTIVE: To investigate the prognostic factors for patients with thoracic ossification of the ligamentum flavum (OLF) and thoracic ossification of posterior longitudinal ligament (OPLL). METHODS: Clinical information of 83 patients suffering from thoracic OLF and OPLL was reviewed retrospectively from January 2006 to June 2010. The related factors such as gender, age, preoperative and postoperative Japanese Orthopedic Association (JOA) score, pathological segment, type of thoracic OPLL, degree of thoracic kyphosis, anteroposterior diameter of OPLL, range of circumferential decompression, cerebrospinal fluid leakage or not and dysfunction or not and carotid lumbar disorders or not were analyzed by Chi-square and Logistic regression. RESULTS: All cases were classified into desirable group (58 cases) and undesirable group (25 cases) based on the postoperative JOA score improvement rate. Comparison of physical characteristics between two groups of age, preoperative JOA and the course of the disease had not statistically significant (P > 0.05). Two groups in pathological segment of thoracic OPLL (χ(2) = 6.290, P = 0.043), the ossification type of OPLL (χ(2) = 5.361, P = 0.021) and dysfunction or not in preoperative (χ(2) = 27.711, P = 0.000) had significant difference. Logistic regression analysis showed that the upper thoracic segments (P = 0.044), beak type ossification (P = 0.023) and with dysfunction in preoperative (P = 0.009) were risk factors. There were 24 patients (28.9%) with cerebrospinal fluid leakage, 3 patients with early postoperative deep infection and neurological deterioration of 2 cases in postoperative. CONCLUSIONS: Patients with ossification on the upper section of thoracic have a better prognosis, but the beaked localized longitudinal ligament ossification in patients and associated with preoperative dysfunction show a poor prognosis, combined jumping segmental ossification and cervical or lumbar severe disorders are the influencing factor for poor prognosis.

Diffusion tensor imaging in the assessment of ossification of the posterior longitudinal ligament: a report on preliminary results in 3 cases and review of the literature.

Cervical spondylotic myelopathy due to ossification of the posterior longitudinal ligament (OPLL) is a common neurosurgical disease that carries high morbidity. OPLL and other degenerative processes cause narrowing of the central canal, with subsequent spinal cord injury. Repeated minor trauma and vascular aberrations have been purported to underlie cervical spondylotic myelopathy, although the exact pathophysiological mechanism is unclear. Regardless, detection of early axonal damage may allow more timely surgical intervention and prediction of functional outcome. Diffusion tensor (DT) imaging of the cervical spine is a novel technique with improved sensitivity compared with conventional anatomical MR imaging that is currently available on most clinical scanners. This review describes the theoretical basis, application, and analysis of DT imaging as it pertains to neurosurgery. Particular emphasis is placed on OPLL.

Ossification of the posterior longitudinal ligament: a review.

Ossification of the posterior longitudinal ligament (OPLL) is most commonly found in men, the elderly, and Asian patients. There are many diseases associated with OPLL, such as diffuse idiopathic skeletal hyperostosis, ankylosing spondylitis, and other spondyloarthropathies. Several factors have been reported to be associated with OPLL formation and progression, including genetic, hormonal, environmental, and lifestyle factors. However, the pathogenesis of OPLL is still unclear. Most symptomatic patients with OPLL present with neurological deficits such as myelopathy, radiculopathy, and/or bowel and bladder symptoms. There are some reports of asymptomatic OPLL. Both static and dynamic factors are related to the development of myelopathy. Plain radiography, CT, and MR imaging are used to evaluate OPLL extension and the area of spinal cord compression. Management of OPLL continues to be controversial. Each surgical technique has some advantages and disadvantages, and the choice of operation should be made case by case, depending on the patient's condition, level of pathology, type of OPLL, and the surgeon's experience. In this paper, the authors attempt to review the incidence, pathology, pathogenesis, natural history, clinical presentation, classification, radiological evaluation, and management of OPLL.