Ossification Of Ligamentum Flavum Research Articles

Surgical Management of Cervical Myelopathy: Current Algorithm

Cervical myelopathy (CM) is a progressive disorder associated with a varied spectrum of etiological factors. Cervical spondylotic myelopathy (CSM) encompasses two-thirds of the cases of CM, while ossified posterior longitudinal ligament (OPLL) and ossified ligamentum flavum (OLF) are significant regional etiological factors. Microvascular disruption, resulting from repetitive dynamic compression or static pressure to the spinal cord, is attributed as a primary pathophysiological mechanism for CM. Magnetic resonance imaging (MRI) is the investigation of choice to assess the spinal cord. Lateral cervical radiographs are crucial for lordosis assessment, and tomographic scans (CT) can delineate the extent of OPLL and OLF. Non-surgical treatment is usually not successful once the patient develops progressive myelopathy. Anterior cervical procedures are ideal for one or two level disc-osteophytes complexes or in patients with kyphotic cervical alignment. Laminoplasty is an effective motion-preserving option in patients with adequate cervical lordosis. Laminectomy or laminoplasty and fusion are optimal for patients with significant preoperative neck pain. Posterior surgery is preferred over anterior surgery for CM involving three or more levels. Older age at presentation, longer duration of symptoms, and severity of pre-operative symptoms are adverse prognostic factors. Progressive cervical myelopathy is a surgical disease, and early intervention is rewarded with better outcomes. Keywords: Cervical myelopathy, Cervical spondylotic myelopathy, OPLL, OLF, Laminoplasty, Laminectomy, ACDF, Cervical corpectomy.

Repeated Recurrence of Ligamentum Flavum Ossification After Posterior Spinal Surgery: A Case Report and Literature Review.

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. 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.

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

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

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

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

Analysis of the surgical strategy and postoperative clinical effect of thoracic ossification of ligament flavum with dural ossification.

PurposeOur research was designed to analyse the postoperative clinical results of patients suffering from single-segment thoracic ossification of the ligamentum flavum (TOLF) combined with dural ossification (DO) who underwent posterior laminar decompression and internal fixation.MethodsThis retrospective research included thirty-two patients who underwent surgery for ossifying the ligamentum flavum in the thoracic spine between January 2016 and January 2020. Patients were fallen into one group included patients with evidence of DO during surgery, and the other group included patients without evidence of DO. We assessed and compared general clinical characteristics and health-related outcomes before surgery and during follow-up.ResultsThe DO group had a longer operation duration, more blood loss, and longer hospital stay (operation time: 94.75 ± 6.78 min vs. 80.00 ± 10.13 min, p < 0.001; blood loss: 331.67 ± 50.06 ml vs. 253.00 ± 48.24 ml, p < 0.001; length of hospital stay: 13.83 ± 2.76 days vs. 10.05 ± 2.33 days, p < 0.001).ComplicationsThere were 12 cases of cerebrospinal fluid leakage and 1 case of superficial wound infection in the DO group. However, the neurological recovery and health-associated quality of life (HRQOL) scores showed no statistically significant changes between the DO and non-DO groups (p > 0.05).ConclusionsPosterior laminectomy and internal fixation combined with intraoperative resection of the ossified ligamentum flavum and dura is an efficient and relatively safe method for treating TOLF with DO, which can provide satisfactory results. Moreover, DO had no significant effect on postoperative neurological recovery and health-related quality of life scores.

Intraoperative neurophysiologic monitoring alteration during en bloc laminectomy surgery for thoracic ossification of ligamentum flavum.

BackgroundThere is real risk during en bloc resection for the treatment of thoracic ossification of ligamentum flavum (TOLF). Intraoperative neurophysiologic monitoring (IONM) has been applied to monitor neurologic functional integration of the spinal cord during surgery. However, the IONM outcome and its relationship with clinical results still needs to be investigated. The purpose of this study is to evaluate the effectiveness and usefulness of IONM in en bloc laminectomy for TOLF.MethodsData from a total of 68 patients with TOLF who received en bloc resection was collected for this retrospective study. IONM of somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs) were analyzed in different patterns of signal alerts, i.e. alert in either MEPs or SSEPs, alert in both MEPs and SSEPs, permanent alert, or recovery during surgery. Postoperative motor and sensory neurological function was evaluated in each patient immediately after surgery and at 12-month follow-up after surgery. The relationship of IONM outcomes and postoperative neurologic function were observed.ResultsFifty of 68 patients did not present significant changes over alert criteria of IONM, neither SSEPs nor MEPs. Those 50 patients without IONM alerts did not show post-operative neurologic deterioration. Four patients presented alert of IONM in a single modality, while 2 patients showed only SSEP alert and 2 patients showed only MEP alert. Fourteen patients showed alerts in both SSEP and MEP, while 8 patients showed one or both signals return to normal during surgery and other 6 showed permanent abnormal electrophysiologic signals to the end of surgery. In the follow-up neurologic test, 3 patients presented transient neurologic complications from among 8 patients with both SSEP and MEP alerts and recovery during surgery. Six patients without recovery of IONM showed permanent neurologic complications after surgery.ConclusionsResults of this study prove the effectiveness and usefulness of IONM in in en bloc laminectomy surgery for TOLF. The patterns of IONM changes correlated with postoperative neurologic functions. Special attention must be paid to the rapid loss of IONM without recovery during spinal decompression.

Factors Predicting Poor Surgical Outcome in Patients with Thoracic Ossified Ligamentum Flavum - Analysis Of 106 Patients in a Tertiary Care Hospital in South India.

Ossified ligamentum flavum (OLF) is the major cause of thoracic myelopathy in our locality. Surgical outcomes and their related factors for patients with thoracic OLF (T-OLF) remain unclear because of the few studies on this condition. The present study aimed to examine the factors predicting poor surgical outcomes and the effectiveness of decompressive laminectomy and OLF resection in patients with T-OLF. A total of 106 patients with T-OLF operated at our institute from 2007 to 2018 were included. The mJOA score was used in neurological assessment preoperatively and during the follow-up. Multiple regression analysis was conducted to know the best correlation between factors and surgical outcomes. The mean mJOA score was 5.67 ± 2.13 preoperatively and 7.50 ± 2.60 postoperatively at the end of follow-up. The recovery rate was 43.29 ± 30.55%. After decompressive laminectomy, the mean mJOA score, modified Nurick score, and Ashworth's grade showed significant improvement (P < 0.001). Multiple regression analysis showed that the age of the patient, associated trauma, OLF level, tuberous type OLF, intramedullary signal change on T2WI, preoperative severity of myelopathy, pre-op mJOA score, and pre-op Nurick grade were significantly correlated with the surgical outcome (P < 0.001). No correlation was identified with the duration of symptoms, dural ossification, dural tear, and CSF leak (P > 0.05). It is important to identify preventable risk factors for poor surgical outcomes for T-OLF. Age of the patient, associated trauma, OLF level, tuberous type OLF, intramedullary signal change on T2WI, preoperative severity of myelopathy, preoperative mJOA score, and Nurick grade were important predictors of surgical outcome in our study series.

Impact of Diffuse Idiopathic Skeletal Hyperostosis on Clinico-Radiological Profiles and Prognosis for Thoracic Ossification of Ligamentum Flavum-Myelopathy: A Propensity-Matched Monocentric Analysis.

Background: Diffuse idiopathic skeletal hyperostosis (DISH) has been evaluated as a potential risk factor of poor surgical outcomes for lumbar spinal stenosis, whereas the influence of DISH on neuroimaging characteristics and postoperative prognosis of patients with thoracic myelopathy has not been established. Therefore, this study aimed to shed light on this issue. Methods: A monocentric study enrolled 167 eligible patients with thoracic ossification of ligamentum flavum (TOLF), who were followed up for at least 2 years. Clinico-radiological parameters and surgical outcomes were compared between the DISH+ and DISH− groups before and after propensity matching. Subgroup analysis was conducted to compare the functional outcomes between mild DISH (M-DISH) and moderately severe DISH (MS-DISH) groups. Results: Fifty-eight patients were diagnosed as DISH, and its prevalence was 34.7%. Patients with DISH presented with older age, more males, taller stature, heavier weight, more commonly diffuse-type TOLF (p < 0.05). The DISH group showed significantly worse recovery rate (RR) at the final follow-up before and after propensity matching (p < 0.01), and slightly lower preoperative VAS, higher postoperative VAS and lower VAS reduction, despite not reaching the significant differences. Subgroup analysis demonstrated that the M-DISH group was associated with the lower mJOA score (p = 0.01) and RR at the final follow-up (p = 0.001), and tended to present higher preoperative VAS than the MS-DISH group. Conclusions: DISH has a significant predisposition to the elderly males with diffuse-type TOLF. Although the presence of M-DISH might bring about a suboptimal surgical outcome, both DISH and non-DISH patients experienced good neurological function improvements and pain relief through thoracic posterior decompression.

Zoning laminectomy for the treatment of ossification of the thoracic ligamentum flavum

Spinal cord injury is a common occurrence during spinal surgery. In this study, we proposed a zoning laminectomy, which could reduce the incidence of nerve injury. We also discussed the safety and clinical efficacy of the zoning laminectomy for thoracic ossification of the ligamentum flavum (TOLF). Forty-five patients with TOLF who underwent zoning laminectomy from October 2016 to February 2020 were included in the retrospective analysis. The Japan Orthopedic Association (JOA) score was used to evaluate clinical outcomes. Meanwhile, the occurrence of complications was recorded. All 45 patients underwent the operation successfully, and the mean follow-up period was 25.3 months, the mean operation time was 160.2min, the average blood loss was 474.2ml, and the average hospital time was 8.0 days. At the final evaluation, the JOA score was significantly higher than the preoperative JOA score (P<0.001) and the overall recovery rate of the JOA score averaged 69.6%. Seventeen patients were graded as excellent, twenty-six as good, and two as fair. The complications included dural tears in nine patients (20.0%), cerebrospinal fluid leakage in seven patients (15.6%), deep infection in one patient (2.2%), and epidural hematoma in one patient (2.2%). All patients recovered well after treatment. Besides, there was no neurological deterioration and thoracic kyphosis occurred. Zoning laminectomy adopts a phased resection from "safe zone" to "danger zone" and defines the safe removal range of the lamina, which reduces the risks of spinal cord injury caused by instrument manipulation. Therefore, it is a safe and effective surgical option.

Unusual site of yellow ligament ossification- cervical spine

The yellow ligament, or Ligamentum flavum, is the ligament that connects the lamina arches of two adjacent vertebrae in the spine [1,2]. This ligament is yellow and has elasticity [3,4]. Ligamentum flavum ossification is an uncommon cause of pressure on the cervical cord [3] [5-7]. Ligamentum flavum ossification commonly occurs in the thoracic cord which can cause myelopathic symptoms in the patient [8,9]. The main cause of this problem is unknown, but it occurs when the soft tissue of the spine is calcified and causes narrowing of the spinal canal [10,11].

Phase I 270° single-incision percutaneous spinal endoscopy for decompression treatment of thoracic spinal stenosis

This study aimed to explore the feasibility of Phase I percutaneous spinal endoscopy with a 270° single incision in the ventral and dorsal dura mater for decompression treatment of thoracic spinal stenosis (TSS). Phase I percutaneous spinal endoscopy with a two-path (posterior and posterolateral approaches) single incision with a 270° decompression was performed in four cases of TSS with compression in the ventral and dorsal dura mater. The affected intervertebral space was located during the surgery, and the ossified ligamentum flavum in the ventral and dorsal dura mater was removed via laminectomy, which formed a decompression space in the thoracic cord. Next, posterolateral transforaminal expansion and plasty were performed to remove the ventral intervertebral disk. The visual analogue scale (VAS) score, thoracic spinal cord function score of the Japanese Orthopaedic Association (JOA) (11-point method), and Oswestry Disability Index (ODI) scores were used to evaluate the clinical efficacy. No dura mater or thoracic nerve injury occurred during the surgery. The symptoms of weakness in the lower extremities improved after the surgery. The postoperative magnetic resonance imaging and computed tomography examinations showed compression removal and dura mater bulging. The postoperative VAS, JOA, and ODI scores improved compared with the preoperative scores. Two surgical trajectories, posterior and posterolateral approaches, were established by a single incision using thoracic spinal canal decompression with Phase I 270° single-incision percutaneous spinal endoscopy. The posterior approach was performed mainly by translaminar unilateral fenestration and bilateral decompression in the ventral and dorsal dura mater, whereas the posterolateral approach was performed by decompression in the ventral dura mater to the midline of the vertebrae. This surgical method could be applied as a safe and feasible minimally invasive treatment for TSS with compression on both the ventral and dorsal dura mater.

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

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

Banner cloud sign: a novel method for the diagnosis of dural ossification in patients with thoracic ossification of the ligamentum flavum.

Dural ossification (DO) is common in patients with ossification of the ligamentum flavum (OLF) and is the leading cause of dural tears. However, the methods used for DO diagnosis are limited. The purpose of this study was to propose a novel CT-based imaging sign, Banner cloud sign (BCs), and clarify its clinical characteristics and correlations with DO. 57 OLF patients who underwent thoracic spine decompression surgery in our single-center between January- and October-2018 were recruited and divided into two groups based on the presence of DO. Patient demographics and radiographic data were analyzed. Hematoxylin-eosin staining and micro-CT were used to detect the micro-morphological changes of DO. The diagnostic value of BCs for DO was assessed by sensitivity and specificity. 12 patients with a total of 19 segments were diagnosed as DO. The incidence of DO was 21.1% (12/57) in OLF patients and 9.5% (19/200) in OLF segments. Patients with DO had a shorter disease duration and a higher incidence of cerebrospinal fluid leakage than those without DO. Hematoxylin-eosin staining and micro-CT showed that the dura mater was ossified and fused with ossified ligamentum flavum, and diffusion along the dura mater, like a banner cloud flying on the mountain. The sensitivity and specificity of BCs in DO diagnosis were 78.9 and 90.6%, respectively. BCs can vividly and intuitively describe the imaging features of DO and has high diagnostic accuracy. It could be a promising and valuable method for the diagnosis of DO.

One-stage combined decompression for cervical ossification of the posterior longitudinal ligament combined with upper thoracic ossification of the ligamentum flavum: Case report

Background and objective: Ossification of posterior longitudinal ligament (OPLL) and ossification of ligamentum flavum (OLF) are common clinical heterotopic ossification diseases and are the main causes of cervicothoracic spinal stenosis and spinal cord damage. However, the incidence of cervical OPLL combined with thoracic OLF is unclear, this clinical condition is difficult to treat, and the surgical approach is not fully established. We report two cases of patients with cervical OPLL combined with upper thoracic OLF treated with one-stage combined decompression Methods: The clinical data of 2 patients diagnosed with cervical OPLL combined with upper thoracic OLF (T1-3) and one-stage surgical treatment from January 2015 to January 2019 were analyzed. Results: Two patients underwent one-stage combined decompression surgery, and the surgery was successfully completed, and there were no postoperative complications such as cerebrospinal fluid leakage and neurological deterioration. One patient’s JOA score increased from 5 points before surgery to 11 points at 2 years of follow-up, and the improvement rate of JOA score was 50%; Another patient’s JOA score increased from 11 points before surgery to 15 points at 2 years of follow-up, and the improvement rate of JOA score was 66.7%. Two patients were satisfied with postoperative recovery. Conclusion: There are few reports on cervical OPLL combined with upper thoracic OLF. We report two cases of patients with cervical OPLL combined with upper thoracic OLF treated with one-stage combined decompression. The postoperative results were satisfactory. However, there were only 2 patients in this study and the follow-up period was short, in the future, high-quality studies with large samples, randomization, and long-term follow-up are still needed to further verify our conclusions

The influence of ossification morphology on surgery outcomes in patients with thoracic ossification of ligamentum flavum (TOLF)

BackgroundTo determine whether there is a correlation between the type of ossification and radiological parameters, modified thoracic JOA scores, and complications in patients with thoracic ossification of ligamentum flavum treated by posterior thoracic surgery.MethodsThis retrospective cohort study included 48 patients with thoracic myelopathy caused by single-level thoracic ossification of ligamentum flavum who underwent thoracic posterior approach surgery in our Hospital o between December 2013 to December 2018. Patients were divided into unilateral, bilateral, and bridged groups in axial position, and beak and round groups in sagittal position. The differences were analyzed according to the ossification morphology.ResultsIn axial myelopathy, there was no significant difference in preop and postop JOA scores and RR among the three groups in axial position (P = 0.884). In sagittal view, there was no significant difference in preoperative JOA score between the two groups (P = 0.710), while the postop JOA score and the recovery rate in the beak group were significantly lower than that of the round group (P = 0.010, P = 0.034). Two-way ANOVA showed that sagittal morphology had a significant effect on postop JOA score (P = 0.028), but axial morphology don’t (P = 0.431); there was no interaction between them (P = 0.444). For the recovery rate, sagittal morphology also had a significant effect (P = 0.043), but axial ossification don’t (P = 0.998); there was no interaction between them (P = 0.479).ConclusionSagittal morphology had a significant adverse effect on postop JOA score and surgical outcome, while axial morphology had no effect on surgical outcome, and there was no interaction between sagittal morphology and axial morphology.

Comparative Clinical and Radiographic Cohort Study: Uniportal Thoracic Endoscopic Laminotomy With Bilateral Decompression by Using the 1-Block Resection Technique and Thoracic Open Laminotomy With Bilateral Decompression for Thoracic Ossified Ligamentum Flavum.

Symptomatic thoracic myelopathy secondary to thoracic ossified ligamentum flavum (OLF) often requires decompression spinal surgery. To compare clinical and radiological outcomes in uniportal endoscopic vs open thoracic decompression for thoracic OLF. Retrospective evaluation of patients who underwent uniportal thoracic endoscopic unilateral laminotomy with bilateral decompression (TE-ULBD) by using the one-block resection technique compared with thoracic open laminotomy (TOL) with bilateral decompression. Radiological outcomes in MRI scan and clinical charts were evaluated. Thirty-five levels of TE-ULBD were compared with 24 levels of TOL. The overall complication rate of TOL was 15% while TE-ULBD was 6.5%. Both TOL and TE-ULBD cohort had significantly improved their visual analog scale (VAS), Oswestry Disability Index, and Japanese Orthopaedic Association (JOA) myelopathy score after operation. Comparative analysis of TE-ULBD performed statistically and significantly better than TOL in improvement of final VAS and JOA scores. The mean difference ± standard deviation of VAS and JOA improvement in final follow-up when compared with preoperative state of TE-ULBD and TOL was 0.717 ± 0.131 and 1.03 ± 0.2, respectively, P < .05. The mean Hirabayashi recovery rates were 94.5% (TE-ULBD) and 56.8% (TOL). There was no statistical difference in change in preoperative and final Oswestry Disability Index and MRI volume at upper endplate, middisk, and lower endplate canal cross-sectional area. Uniportal TE-ULBD achieved significantly improved pain and neurological recovery with sufficient spinal canal decompression, as compared with thoracic open laminectomy for patients with myelopathy secondary to OLF in our cohort.

Commentary: Comparative Clinical and Radiographic Cohort Study: Uniportal Thoracic Endoscopic Laminotomy With Bilateral Decompression by Using the 1-Block Resection Technique and Thoracic Open Laminotomy With Bilateral Decompression for Thoracic Ossified Ligamentum Flavum.

Commentary: Comparative Clinical and Radiographic Cohort Study: Uniportal Thoracic Endoscopic Laminotomy With Bilateral Decompression by Using the 1-Block Resection Technique and Thoracic Open Laminotomy With Bilateral Decompression for Thoracic Ossified Ligamentum Flavum.

Symptomatic thoracic ossified ligamentum flavum in achondroplasia: A case report and literature review

Background: In a patient with achondroplasia, it is rare to encounter thoracic cord compression due to both spinal stenosis and ossification of the yellow ligament (OYL).Case Description: A 33-year-old achondroplastic female presented with a progressive spastic paraparesis attributed to thoracic stenosis combined with T10-T11 OYL. Following a laminectomy, the patient demonstrated a marked recovery of neurological function.Conclusion: This case and 12 others from the literature demonstrated that achondroplastic patients who present with myelopathy secondary to thoracic stenosis and OYL can be readily diagnosed with MR/CT and successfully treated utilizing decompressive laminectomies with/without fusions (i.e., for those crossing the thoracolumbar junction).

Connexin 43 affects thoracic ossification of ligamentum flavum by regulating the p38 MAPK-RUNX2 signaling pathway

This study aimed to investigate the role of connexin 43 (CX43) in thoracic ossification of ligamentum flavum (TOLF) based on the p38 mitogen-activated protein kinase (p38MAPK)-runt-related transcription factor 2 (RUNX2) pathway. Immunohistochemistry was used to detect CX43 expression in TOLF and non-TOLF patients, fibroblasts of TOLF were isolated and induced osteogenic differentiation, and CX43 expression was detected by western blot analysis (WB). In addition, si-CX43 was used to intervene CX43, and SB203580 was used to inhibit the p38MAPK. The expressions of bone differentiation marker protein were detected by WB, and the ossification ability was analyzed by alizarin red staining. The interaction between RUNX2 and CX43 was identified by dual-luciferase reporter assay. Results found that CX43 was highly expressed during TOLF, and si-CX43 could inhibit the expression of alkaline phosphatase (ALP) and osteopontin (OPN), as well as inhibit TOLF and the p38MAPK-RUNX2 pathway. In addition, SB203580 showed a synergistic effect with si-CX43 to further inhibit TOLF and the expression of RUNX2. The dual-luciferase reporter assay confirmed that RUNX2 could bind to the CX43 promoter. In conclusion, CX43 promotes TOLF, which may be mediated by p38MAPK-RUNX2, and RUNX2 binds to the CX43 promoter to form a positive feedback regulatory loop during TOLF.

Risk Factors for Poor Outcomes of Thoracic Ossification of Ligamentum Flavum After Laminectomy.

BackgroundThoracic ossification of ligamentum flavum (TOLF) is a common pathological change of the thoracic ligamentum flavum. Identifying the risk factors for poor prognosis is critical for choosing suitable surgical methods.Material/MethodsA total of 64 patients with TOLF after laminectomy were reviewed between January 2010 and April 2018 at the Department of Spine Surgery of the Third Hospital of Hebei Medical University. The Japanese Orthopaedic Association (JOA) scale was used to evaluate the neurological function of patients. According to the average JOA improvement rate, the patients were divided into the good prognosis group (Group GP) and the poor prognosis group (Group PP). Multivariate logistic regression analysis was used to identify the risk factors for poor outcomes.ResultsThe average JOA improvement rate was 53.04±24.29%. Group GP comprised 33 patients, while Group PP comprised 31 patients. Duration of preoperative symptoms (P=0.005), intramedullary high signal intensity (P=0.001), dural ossification rate (P=0.002), and sagittal configuration of ossification (P=0.012) were significantly higher in Group PP than in Group GP. Multivariate logistic analysis showed that duration of preoperative symptoms (P=0.022), intramedullary high signal intensity (P=0.010), dural ossification (P=0.007) and sagittal configuration of ossification (P=0.029) were risk factors for poor outcomes of TOLF after laminectomy.ConclusionsAfter surgical treatment of TOLF, the symptoms of some patients either recovered slowly or did not recover. Longer than 17 months of preoperative symptoms, intramedullary high signal intensity, dural ossification, and sagittal configuration of ossification were the risk factors for poor outcomes of TOLF after laminectomy.