Comparative Analysis of Postoperative Sagittal Balance in Expansive Open-Door Laminoplasty versus Laminectomy with Fusion for Multilevel Ossification of Posterior Longitudinal Ligament: A Retrospective Study.

BACKGROUND This single-center study included 80 patients with multilevel cervical ossification of the posterior longitudinal ligament (OPLL) and aimed to compare postoperative sagittal balance following treatment with expansive open-door laminoplasty (LP) vs total laminectomy with fusion (LF). MATERIAL AND METHODS Data of 80 patients with multilevel OPLL treated with LP vs LF between January 2017 and January 2022 were retrospectively analyzed. The basic data, cervical sagittal parameters, and clinical outcomes of the patients were counted in the preoperative and postoperative periods, and complications were recorded. Forty patients underwent LP and 40 underwent LF. Cervical sagittal parameters were compared between and within the 2 groups. Clinical outcomes and complications were compared between the 2 groups. RESULTS At last follow-up, the postoperative C2-C7 Cobb angel, T1 slope (T1S), and C7 slope (C7S) were significantly higher in the LF group than in the LP group (P<0.001). C2-C7 SVA (cSVA) was slightly higher in the LF group (P>0.05) and significantly higher in the LP group (P<0.05). The incidence of postoperative complications in the LP group was significantly lower than in the LF group (P=0.02). The postoperative scores on the Visual Analog Scale (VAS), Neck Disability Index (NDI), and Japanese Orthopedic Association (JOA) were significantly improved in both groups (P<0.001). CONCLUSIONS Both procedures had good outcomes in neurological improvement. After posterior surgery, the cervical vertebrae all showed a tilting forward. Compared to LP, LF may change cervical balance in Cobb angel, T1S. LF has better efficacy in improving cervical lordosis compared with LP. Patients with high T1 slope after surgery may has more axial pain.

[Treatment of cervical ossification of posterior longitudinal ligament with titanium alloy trabecular bone three-dimensional printed artificial vertebral body].

Objective: To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL). Methods: A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C 2-7Cobb angle ( P>0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C 2-7 Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed. Results: The operation time and incidence of complications were significantly lower in the study group than in the control group ( P<0.05), while the difference in intraoperative blood loss between the two groups was not significant ( P>0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference ( t=0.809, P=0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences ( P<0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group ( P<0.05); but there was no significantly difference in VAS score and NDI between the two groups ( P>0.05). Imaging re-examination showed that the vertebral height and C 2-7Cobb angle of the two groups significantly increased at 3 and 12 months after operation ( P<0.05), and there was no significant difference between 3 and 12 months after operation ( P>0.05). At each time point, the vertebral height and C 2-7Cobb angle of the study group were significantly higher than those of the control group ( P<0.05), and the implant subsidence rate was significantly lower than that of the control group ( P<0.05). However, there was no significant difference in intervertebral fusion rate between the two groups ( P>0.05). Conclusion: Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.

Integrin αVß3 antagonist-c(RGDyk) peptide attenuates the progression of ossification of the posterior longitudinal ligament by inhibiting osteogenesis and angiogenesis.

BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL), an emerging heterotopic ossification disease, causes spinal cord compression, resulting in motor and sensory dysfunction. The etiology of OPLL remains unclear but may involve integrin αVß3 regulating the process of osteogenesis and angiogenesis. In this study, we focused on the role of integrin αVß3 in OPLL and explored the underlying mechanism by which the c(RGDyk) peptide acts as a potent and selective integrin αVß3 inhibitor to inhibit osteogenesis and angiogenesis in OPLL. METHODS: OPLL or control ligament samples were collected in surgery. For OPLL samples, RNA-sequencing results revealed activation of the integrin family, particularly integrin αVß3. Integrin αVß3 expression was detected by qPCR, Western blotting, and immunohistochemical analysis. Fluorescence microscopy was used to observe the targeted inhibition of integrin αVß3 by the c(RGDyk) peptide on ligaments fibroblasts (LFs) derived from patients with OPLL and endothelial cells (ECs). The effect of c(RGDyk) peptide on the ossification of pathogenic LFs was detected using qPCR, Western blotting. Alkaline phosphatase staining or alizarin red staining were used to test the osteogenic capability. The effect of the c(RGDyk) peptide on angiogenesis was determined by EC migration and tube formation assays. The effects of the c(RGDyk) peptide on heterotopic bone formation were evaluated by micro-CT, histological, immunohistochemical, and immunofluorescence analysis in vivo. RESULTS: The results indicated that after being treated with c(RGDyk), the osteogenic differentiation of LFs was significantly decreased. Moreover, the c(RGDyk) peptide inhibited the migration of ECs and thus prevented the nutritional support required for osteogenesis. Furthermore, the c(RGDyk) peptide inhibited ectopic bone formation in mice. Mechanistic analysis revealed that c(RGDyk) peptide could inhibit osteogenesis and angiogenesis in OPLL by targeting integrin αVß3 and regulating the FAK/ERK pathway. CONCLUSIONS: Therefore, the integrin αVß3 appears to be an emerging therapeutic target for OPLL, and the c(RGDyk) peptide has dual inhibitory effects that may be valuable for the new therapeutic strategy of OPLL.

Sorafenib inhibits ossification of the posterior longitudinal ligament by blocking LOXL2-mediated vascularization.

Ossification of the Posterior Longitudinal Ligament (OPLL) is a degenerative hyperostosis disease characterized by the transformation of the soft and elastic vertebral ligament into bone, resulting in limited spinal mobility and nerve compression. Employing both bulk and single-cell RNA sequencing, we elucidate the molecular characteristics, cellular components, and their evolution during the OPLL process at a single-cell resolution, and validate these findings in clinical samples. This study also uncovers the capability of ligament stem cells to exhibit endothelial cell-like phenotypes in vitro and in vivo. Notably, our study identifies LOXL2 as a key regulator in this process. Through gain-and loss-of-function studies, we elucidate the role of LOXL2 in the endothelial-like differentiation of ligament cells. It acts via the HIF1A pathway, promoting the secretion of downstream VEGFA and PDGF-BB. This function is not related to the enzymatic activity of LOXL2. Furthermore, we identify sorafenib, a broad-spectrum tyrosine kinase inhibitor, as an effective suppressor of LOXL2-mediated vascular morphogenesis. By disrupting the coupling between vascularization and osteogenesis, sorafenib demonstrates significant inhibition of OPLL progression in both BMP-induced and enpp1 deficiency-induced animal models while having no discernible effect on normal bone mass. These findings underscore the potential of sorafenib as a therapeutic intervention for OPLL.

Comparison of radiological and clinical outcomes of cervical laminoplasty versus lateral mass screw fixation in patients with ossification of the posterior longitudinal ligament.

PURPOSE: This study aimed to compare cervical sagittal parameters and clinical outcomes between patients undergoing cervical laminoplasty(CL) and those undergoing lateral mass screw fixation(LMS). METHODS: We retrospectively studied 67 patients with multilevel ossification of the posterior longitudinal ligament (OPLL) of the cervical spine who underwent lateral mass screw fixation (LMS = 36) and cervical laminoplasty (CL = 31). We analyzed cervical sagittal parameters (C2-7 sagittal vertical axis (C2-7 SVA), C0-2 Cobb angle, C2-7 Cobb angle, C7 slope (C7s), T1 slope (T1s), and spino-cranial angle (SCA)) and clinical outcomes (visual analog scale [VAS], neck disability index [NDI], Japanese Orthopaedic Association [JOA] scores, recovery rate (RR), and minimum clinically significant difference [MCID]). The cervical sagittal parameters at the last follow-up were analyzed by binary logistic regression. Finally, we analyzed the correlation between the cervical sagittal parameters and each clinical outcome at the last follow-up after surgery in both groups. RESULTS: At the follow-up after posterior decompression in both groups, the mean values of C2-C7 SVA, C7s, and T1s in the LMS group were more significant than those in the CL group (P ≤ 0.05). Compared with the preoperative period, C2-C7 SVA, T1s, and SCA gradually increased, and the C2-C7 Cobb angle gradually decreased after surgery (P < 0.05). The improvement in the JOA score and the recovery rate was similar between the two groups, while the improvement in the VAS-N score and NDI score was more significant in the CL group (P = 0.001; P = 0.043). More patients reached MCID in the CL group than in the LMS group (P = 0.036). Binary logistic regression analysis showed that SCA was independently associated with whether patients reached MCID at NDI postoperatively. SCA was positively correlated with cervical NDI and negatively correlated with cervical JOA score at postoperative follow-up in both groups (P < 0.05); C2-7 Cobb angle was negatively correlated with cervical JOA score at postoperative follow-up (P < 0.05). CONCLUSION: CL may be superior to LMS in treating cervical spondylotic myelopathy caused by OPLL. In addition, smaller cervical SCA after posterior decompression may suggest better postoperative outcomes.

Comparison of Postoperative Complications and Outcomes in Anterior Cervical Spine Surgery: Ossification of the Posterior Longitudinal Ligament Versus Cervical Spondylotic Myelopathy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To compare the frequency of complications and outcomes between patients with ossification of the posterior longitudinal ligament (OPLL) of the cervical spine and those with cervical spondylotic myelopathy (CSM) who underwent anterior surgery. SUMMARY OF BACKGROUND DATA: Anterior cervical spine surgery for OPLL is an effective surgical procedure; however, it is complex and technically demanding compared with the procedure for CSM. Few reports have compared postoperative complications and clinical outcomes after anterior surgeries between the 2 pathologies. METHODS: Among 1434 patients who underwent anterior cervical spine surgery at 3 spine centers within the same spine research group from January 2011 to March 2021, 333 patients with OPLL and 488 patients with CSM were retrospectively evaluated. Demographics, postoperative complications, and outcomes were reviewed by analyzing medical records. In-hospital and postdischarge postoperative complications were investigated. Postoperative outcomes were evaluated 1 year after the surgery using the Japanese Orthopaedic Association score. RESULTS: Patients with OPLL had more comorbid diabetes mellitus preoperatively than patients with CSM ( P <0.001). Anterior cervical corpectomies were more often performed in patients with OPLL than in those with CSM (73.3% and 14.5%). In-hospital complications, such as reoperation, cerebrospinal fluid leak, C5 palsy, graft complications, hoarseness, and upper airway complications, occurred significantly more often in patients with OPLL. Complications after discharge, such as complications of the graft bone/cage and hoarseness, were significantly more common in patients with OPLL. The recovery rate of the Japanese Orthopaedic Association score 1 year postoperatively was similar between patients with OPLL and those with CSM. CONCLUSION: The present study demonstrated that complications, both in-hospital and after discharge following anterior spine surgery, occurred more frequently in patients with OPLL than in those with CSM.

Factors Associated With Repeat Surgery in Cervical Ossification of the Posterior Longitudinal Ligaments: Minimum 8-year Follow-up Study.

STUDY DESIGN: Single-center retrospective study. OBJECTIVE: The objective of this study is to identify the factors leading to repeat surgery in patients with cervical ossification of the longitudinal ligament (OPLL) during a minimal 8-year follow-up after the initial surgery. SUMMARY OF BACKGROUND DATA: The long-term effects of cervical OPLL are well known, but it's not always clear how many patients need to have surgery again because their neurological symptoms get worse. METHODS: This study is included 117 patients who underwent surgery for cervical OPLL and had a follow-up of at least 8 years. OPLL type, surgical extent, surgical method, and sagittal radiological parameters were measured, and OPLL characteristics were analyzed. RESULTS: The average age of patients at the time of surgery was 53.2 years, with a male-to-female ratio of 78:39. The median follow-up duration was 122 months (96-170 mo). Out of the total, 20 cases (17.1%) necessitated repeat surgery, among which 8 cases required surgery at the same site as the initial operation. The highest rate of repeat surgery was observed in patients who underwent total laminectomy without fusion (TL), where 6 out of 21 patients (29%) needed a second surgery, and 5 of these (23%) involved the same surgical site. Patients who underwent repeat surgery at the same site exhibited a greater range of motion (ROM) one year postsurgery (16.4 ± 8.5° vs. 23.1 ± 12.7°, P =0.041). In addition, the ROM at 1 year was higher in patients who underwent TL compared with those who had laminoplasty. Furthermore, the recurrence rate for hill-shape OPLL was higher at 30.8% compared to 10% for plateau-shape OPLL ( P = 0.05). CONCLUSION: Larger cervical ROM 1 year after surgery is related to repeat surgery at the same level as previous surgery, especially in laminectomy without fusion surgery.

[Clinical observation on the treatment of ossification of the posterior longitudinal ligament of the cervical spine using 3D printed self-stable zero-profile artificial vertebral body].

Objective: To observe the clinical efficacy of a 3D printed self-stable zero-profile artificial vertebral body for anterior cervical corpectomy decompression and fusion in the treatment of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. Methods: In this prospective randomized controlled trial, patients diagnosed with OPLL in Luohe Central Hospital from January to July 2022 were divided into a zero-profile group (3D printed self-stable zero-profile artificial vertebral body was used for internal fixation and fusion after anterior cervical subtotal decompression,) and titanium-mesh group (titanium-mesh and titanium plate were used for internal fixation and fusion after anterior cervical subtotal decompression) according to envelope random method. Operation time, intraoperative blood loss, Japanese Orthopaedic Association (JOA) score and improvement rate, incidence of postoperative prosthesis subsidence, and bone graft fusion were recorded and compared between the two groups. Results: Finally, 21 patients in the zero notch group and 20 patients in the titanium mesh group were included in the study and were followed-up. In the zero-profile group, there were 16 males and 5 females, aged (48.0±12.7) years. In the titanium-mesh group, there were 14 males and 6 females, aged (49.8±10.2) years. All the 41 patients successfully completed the operation. In the zero-profile group, the surgical time was (50.04±8.45) minutes, the blood loss was (95.38±26.07) ml and the hospitalization cost was (42.32±6.12) thousand yuan. In the titanium-mesh group, the surgical time was (59.20±11.95) minutes, the blood loss was (93.10±27.86) ml and the hospitalization cost was (42.10±6.71) thousand yuan. The surgical time in the zero-profile group was shorter than that in the titanium-mesh group (P=0.007), and there was no statistically significant difference in blood loss and hospitalization costs between the two groups (both P>0.05). The 41 patients were followed-up for (14.29±1.45) months. Four cases (20.0%) in the titanium mesh group experienced swallowing difficulties and 0 cases in the zero incision group, the difference between the two groups was statistically significant (P=0.048). No intraoperative hematoma, spinal cord nerve recompression, airway crisis, incision infection complications, and no steel plate or screw breakage or displacement occurred after surgery. At the last follow-up, all cases had bone fusion. At the follow-up of 12 months after surgery, the JOA score of the zero incision group increased from preoperative (10.33±1.71) points to (15.47±0.81) points, with an improvement rate of 76.1%±15.7%; the JOA score of the titanium mesh group increased from (10.30±1.75) points to (15.30±0.92) points, with an improvement rate of 73.2%±16.7%; there was no statistically significant difference in improvement rate between the two groups (P=0.580). At the follow-up of 12 months after surgery, 1 case (4.8%) in the zero incision group and 8 cases (40.0%) in the titanium mesh group experienced implant sinking, and the difference between the two groups was statistically significant (P=0.009). Conclusion: Compared with titanium-mesh, 3D printed self-stable zero-profile artificial vertebral body for the treatment of OPLL of the cervical spine can achieve good surgical efficacy, shorter surgical time, lower incidence of postoperative chronic swallowing discomfort, and can provide a better bone material bonding interface and be less prone to prosthesis settlement.

Prospective Investigation of the Posterior Longitudinal Ligament and Disc Complex after Posterior Stabilization and Decompression Surgery in Patients With Non-OPLL (Ossification of the Posterior Longitudinal Ligament) Cervical Spondylotic Myelopathy.

BACKGROUND: Cervical spondylotic myelopathy (CSM) is a prevalent cause of spinal cord dysfunction in adults, primarily from degenerative changes. The efficacy of treatment strategies, especially surgical approaches, remains debated. OBJECTIVE: This study aimed to assess the long-term impact of posterior fusion laminectomy on the posterior longitudinal ligament (PLL) thickness, disc complex, and myelomalacia signal changes in CSM patients. METHODS: A single-centre, prospective study from January 2020 to December 2021 included CSM patients without ossified posterior longitudinal ligament (OPLL). Magnetic resonance imaging (MRI) data from baseline, 6, and 12 months postoperatively were collected. Measurements on the MRI were performed using the Osirix MD software, focusing on the PLL width, myelopathic foci dimensions, and canal diameter. RESULTS: Out of the 82 initially enrolled patients, 64 were considered for analysis. Postoperatively, a significant reduction in PLL width and myelopathic foci dimensions was observed, alongside a considerable increase in the canal diameter. Clinical outcomes based on the Modified Japanese Orthopaedic Association (mJOA) scale also showcased marked improvements post-surgery. CONCLUSIONS: Posterior fusion laminectomy effectively reduces anterior pressure in CSM patients. This treatment may represent an optimal surgical approach for selected CSM cases. Furthermore, more extensive studies with extended follow-up are advocated.

A rare case of intervertebral disc calcification combined with ossification of the posterior longitudinal ligament in a child: a case report and literature review.

BACKGROUND: Intervertebral disc calcification (IDC) combined with calcification in children has been sporadically reported, while ossification of the posterior longitudinal ligament (OPLL) in the cervical spine in pediatric patients is exceedingly rare. The aim of this study is to investigate the potential prognosis and outcomes associated with this condition. CASE PRESENTATION: We present an unusual case involving a 10-year-old Chinese child diagnosed with calcified cervical disc herniation and ossification of the posterior longitudinal ligament. Conservative treatment measures were implemented, and at the 1-month and 6-month follow-up, the patient's pain exhibited significant improvement. Subsequent cervical MRI and CT scans revealed the complete disappearance of OPLL and substantial absorption of the calcified disc. During the three-month follow-up, CT demonstrated slight residual disc calcification, however, the patient remained asymptomatic with no discernible limitation in cervical motion. CONCLUSIONS: We conducted a comprehensive review of several cases presenting with the same diagnosis. It is noteworthy that IDC combined with OPLL in children constitutes a rare clinical entity. Despite imaging indications of potential spinal canal occupation, the majority of such cases demonstrate complete absorption following conservative treatment, with OPLL exhibiting a faster absorption rate than calcified discs.

Differences in the Demographics and Clinical Characteristics between the Ossification of the Posterior Longitudinal Ligament and Ossification of the Ligamentum Flavum in Patients Who Underwent Thoracic Spinal Surgery for Compressive Myelopathy.

Ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) are related diseases associated with the ossification of spinal ligaments that can occasionally lead to thoracic myelopathy. We retrospectively analyzed the clinical data of 34 consecutive patients who underwent thoracic spinal surgeries for OPLL and/or OLF at our hospital between July 2010 and June 2022, and statistically compared data between patients with thoracic OPLL (TOPLL; n = 12) and those with thoracic OLF (TOLF; n = 22). The mean age of the TOPLL group was significantly lower than that of the TOLF group (53.7 vs. 68.4 years). The TOPLL group exhibited a greater female predominance than the TOLF group (58.3% vs. 18.2%). The median body mass index of the TOPLL group was significantly higher than that of the TOLF group (33.0 vs. 26.0 kg/m2). Patients with TOPLL significantly required instrumented fusion and repetitive surgical intervention more than those with TOLF (83.3% vs. 9.1%; 50.0% vs. 0.0%). Although neurological deterioration just after the intervention was more common in patients with TOPLL (41.7% vs. 4.6%), no difference was observed in thoracic Japanese Orthopaedic Association score and recovery rate in the chronic phase between TOPLL and TOLF. The TOPLL group had a younger onset, female dominance, and a greater degree of obesity when compared with the TOLF group. The surgery for TOPLL is challenging, considering that it requires long-range decompression and fusion, subsequent operations, careful management, and long-term follow-up, when compared to TOLF, which necessitates only simple decompression.

Patients with a large ossification of the posterior longitudinal ligament have a higher incidence of arteriosclerosis in the carotid artery.

PURPOSE: This study aimed to investigate the impact of the severity of cervical ossification of the posterior longitudinal ligament (OPLL) on the incidence of arteriosclerosis in the carotid artery. METHODS: Patients with OPLL-induced cervical myelopathy were prospectively enrolled. The study involved analyzing patient characteristics, blood samples, computed tomography scans of the spine, and intima-media thickness (IMT) measurements of the common carotid artery. Patients were divided into two groups based on the size of the cervical OPLL to compare demographic data, comorbidities, and the presence of thickening of the carotid intima-media (max IMT ≥ 1.1 mm). RESULTS: The study included 96 patients (mean age: 63.5 years; mean body mass index: 26.9 kg/m2; 71.8% male; 35.4% with diabetes mellitus). The mean maximum anteroposterior (AP) diameter of the OPLL was 4.9 mm, with a mean occupancy ratio of 43%. The mean maximum IMT was 1.23 mm. Arteriosclerosis of the carotid artery was diagnosed in 62.5% of the patients. On comparing the two groups based on OPLL size, the group with larger OPLL (≥ 5 mm) had a higher BMI and a greater prevalence of carotid intima-media thickening. This significant difference in the prevalence of carotid intima-media thickening persisted even after adjusting for patient backgrounds using propensity score matching. CONCLUSIONS: Patients with a larger cervical OPLL showed a higher frequency of intima-media thickening in the carotid artery.

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.

Different cutoff value of motor evoked potentials for the postoperative outcome in the ossification of the posterior longitudinal ligament surgery in the cervical and thoracic spine.

BACKGROUND CONTEXT: Transcranial muscle motor evoked potentials (Tc-mMEPs), a key component of intraoperative neurophysiologic monitoring (IONM), effectively reflect the changes in corticospinal tract integrity and are closely related to the occurrence of the postoperative motor deficit (PMD). Most institutions have applied a specified (fixed) alarm criterion for the heterogeneous groups in terms of etiologies or lesion location. However, given the high risk of PMD in ossification of the posterior longitudinal ligament (OPLL) surgery, it is essential to determine a tailored cutoff value for IONM. PURPOSE: We aimed to establish the intraoperative cutoff value of Tc-mMEPs reduction for predicting PMD in OPLL according to lesion levels. DESIGN: Retrospective analysis using a review of electrical medical records. PATIENT SAMPLE: In this study, we included 126 patients diagnosed with OPLL, who underwent surgery and IONM. OUTCOME MEASURES: The occurrence of PMD immediately and 1 year after operation, as well as the decrement of intraoperative Tc-mMEPs amplitude. METHODS: We analyzed OPLL surgery outcomes using Tc-mMEPs monitoring. Limbs with acceptable baseline Tc-mMEPs in the tibialis anterior or abductor hallucis were included in the final set. PMD was defined as a ≥1 decrease in Medical Research Council score in the legs, and it was evaluated immediately and 1year after operation. The reduction ratios of Tc-mMEPs amplitude compared with baseline value were calculated at the two time points: the maximal decrement during surgery and at the end of surgery. Receiver operating characteristic curve analysis was used to determine the cutoff value of Tc-mMEPs amplitude decrement for predicting PMDs. RESULTS: In total, 203 limbs from 102 patients with cervical OPLL and 42 limbs from 24 patients with thoracic OPLL were included. PMD developed more frequently in thoracic lesions than in cervical lesions (immediate, 9.52% vs 2.46%; 1 year, 4.76% vs 0.99%). The Tc-mMEPs amplitude cutoff point at the end of surgery for PMD (both immediate and 1-year) was a decrease of 93% in cervical and 50% in thoracic OPLL surgeries. Similarly, the Tc-mMEPs amplitude cutoff point at the maximal decrement during surgery for PMD (both immediate and 1 year) was a reduction of 97% in cervical and 85% in thoracic OPLL surgeries. CONCLUSIONS: The thoracic lesion exhibited a lower cutoff value than the cervical lesion for both immediate and long-term persistent PMD in OPLL surgery (Tc-mMEPs at the end of surgery measuring 93% vs 50%; and Tc-mMEPs at the maximal decrement measuring 97% vs 85% for cervical and thoracic lesions, respectively). To enhance the reliability of monitoring, considering the application of tailored alarm criteria for Tc-mMEPs changes based on lesion location in OPLL could be beneficial.

A Convolutional Neural Network for Automated Detection of Cervical Ossification of the Posterior Longitudinal Ligament using Magnetic Resonance Imaging.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: We aimed to develop and validate a convolutional neural network (CNN) model to distinguish between cervical ossification of posterior longitudinal ligament (OPLL) and multilevel degenerative spinal stenosis using Magnetic Resonance Imaging (MRI) and to compare the diagnostic ability with spine surgeons. SUMMARY OF BACKGROUND DATA: Some artificial intelligence models have been applied in spinal image analysis and many of promising results were obtained; however, there was still no study attempted to develop a deep learning model in detecting cervical OPLL using MRI images. MATERIALS AND METHODS: In this retrospective study, 272 cervical OPLL and 412 degenerative patients underwent surgical treatment were enrolled and divided into the training (513 cases) and test dataset (171 cases). CNN models applying ResNet architecture with 34, 50, and 101 layers of residual blocks were constructed and trained with the sagittal MRI images from the training dataset. To evaluate the performance of CNN, the receiver operating characteristic curves of 3 ResNet models were plotted and the area under the curve were calculated on the test dataset. The accuracy, sensitivity, and specificity of the diagnosis by the CNN were calculated and compared with 3 senior spine surgeons. RESULTS: The diagnostic accuracies of our ResNet34, ResNet50, and ResNet101 models were 92.98%, 95.32%, and 97.66%, respectively; the area under the curve of receiver operating characteristic curves of these models were 0.914, 0.942, and 0.971, respectively. The accuracies and specificities of ResNet50 and ResNet101 models were significantly higher than all spine surgeons; for the sensitivity, ResNet101 model achieved better values than that of the 2 surgeons. CONCLUSION: The performance of our ResNet model in differentiating cervical OPLL from degenerative spinal stenosis using MRI is promising, better results were achieved with more layers of residual blocks applied.

Bone Turnover Markers in Patients With Ossification of the Posterior Longitudinal Ligament in the Thoracic Spine.

STUDY DESIGN: A prospective, single-center, observational study. OBJECTIVE: To explore the association between serum levels of bone turnover markers and ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine. SUMMARY OF BACKGROUND DATA: The relationship between bone turnover markers, such as N-terminal propeptide of type I procollagen (PINP) or tartrate-resistant acid phosphate 5b (TRACP-5b), and OPLL has previously been examined. However, the correlation between these markers and thoracic OPLL, which is more severe than cervical-only OPLL, remains unclear. METHODS: This prospective study included 212 patients from a single institution with compressive spinal myelopathy and divided them into those without OPLL (Non-OPLL group, 73 patients) and those with OPLL (OPLL group, 139 patients). The OPLL group was further subdivided into cervical OPLL (C-OPLL, 92 patients) and thoracic OPLL (T-OPLL, 47 patients) groups. Patients' characteristics and biomarkers related to bone metabolism, such as calcium, inorganic phosphate (Pi), 25-hydroxyvitamin D, 1α,25 dihydroxyvitamin D, PINP, and TRACP-5b, were compared between the Non-OPLL and OPLL groups, as well as the C-OPLL and T-OPLL groups. Bone metabolism biomarkers were also compared after adjusting for age, sex, body mass index, and the presence of renal impairment using propensity score-matched analysis. RESULTS: The OPLL group had significantly lower serum levels of Pi and higher levels of PINP versus the Non-OPLL group as determined by propensity score-matched analysis. The comparison results between the C-OPLL and T-OPLL groups using a propensity score-matched analysis showed that T-OPLL patients had significantly higher concentrations of bone turnover markers, such as PINP and TRACP-5b, compared with C-OPLL patients. CONCLUSIONS: Increased systemic bone turnover may be associated with the presence of OPLL in the thoracic spine, and bone turnover markers such as PINP and TRACP-5b can help screen for thoracic OPLL.

Clinical outcome of surgical management of mild cervical compressive myelopathy based on minimum clinically important difference.

BACKGROUND CONTEXT: Cervical compressive myelopathy (CCM), caused by cervical spondylosis (cervical spondylotic myelopathy [CSM]) or ossification of the posterior longitudinal ligament (OPLL), is a common neurological disorder in the elderly. For moderate/severe CCM, surgical management has been the first-line therapeutic option. Recently, surgical management is also recommended for mild CCM, and a few studies have reported the surgical outcome for this clinical population. Nonetheless, the present knowledge is insufficient to determine the specific surgical outcome of mild CCM. PURPOSE: To examine the surgical outcomes of mild CCM while considering the minimum clinically important difference (MCID). STUDY DESIGN: Retrospective study. PATIENT SAMPLE: Patients who underwent subaxial cervical surgery for CCM caused by CSM and OPLL between 2013 and 2022 were enrolled. OUTCOME MEASURES: The Japanese Orthopedic Association score (JOA score) was employed as the clinical outcomes. Based on previous reports, the JOA score threshold to determine mild myelopathic symptoms was set at ≥14.5 points, and the MCID of the JOA score for mild CCM was set at 1 point. METHODS: The patients with a JOA score of ≥14.5 points at baseline were stratified into the mild CCM and were examined while considering the MCID. The mild CCM cohort was dichotomized into the improvement group, including the patients with an achieved MCID (JOA score ≥1 point) or with a JOA score of 17 points (full mark) at 1 year postoperatively, and the nonimprovement group, including the others. Demographics, symptomatology, radiographic findings, and surgical procedure were compared between the two groups and studied using the receiver operating characteristic (ROC) curve. RESULTS: Of 335 patients with CCM, 43 were stratified into the mild CCM cohort (mean age, 58.5 years; 62.8% male). Among them, 25 (58.1 %) patients were assigned to the improvement group and 18 (41.9 %) were assigned to the nonimprovement group. The improvement group was significantly younger than the nonimprovement group; however, other variables did not significantly differ. ROC curve analysis showed that the optimal cutoff point of the patient's age to discriminate between the improvement and nonimprovement groups was 58 years with an area under the curve of 0.702 (p=.015). CONCLUSIONS: In the present study, the majority of patients with mild CCM experienced improvement reaching the MCID of JOA score at 1 year postoperatively. The present study suggests that for younger patients with mild CCM, especially those aged below 58 years, subjective neurological recovery is more likely to be obtained. Meanwhile, the surgery takes on a more prophylactic significance to halt disease progression for older patients. The results of this study can help in the decision-making process for this clinical population.

Assessing Range of Motion Gap in Circumferential Surgery for Cervical Myelopathy due to Ossification of the Posterior Longitudinal Ligament.

OBJECTIVE: Only a few studies have investigated the gap range of motion (gROM) in cervical myelopathy or deformity caused by ossification of the posterior longitudinal ligament (OPLL). The aim of this study is to investigate the correlation between the individual gROM and the postoperative clinical outcomes of patients with OPLL. METHODS: Consecutive patients of cervical myelopathy caused by OPLL were analyzed retrospectively. The clinical outcomes were evaluated using Visual Analogue Scale scores of the neck and arm pain and the Japanese Orthopaedic Association scores. Radiologic measurements included flexion ROM (fROM), which was defined as the difference of cervical lordosis in flexion and neutral positions, extension ROM (eROM), defined as the difference between neutral and extension positions, and gROM, defined as the difference between fROM and eROM. Patients were grouped by the values of gROM, and comparisons of all outcomes were made between the groups. RESULTS: A total of 42 patients underwent surgery. The patients with greater gROM did not differ from those with smaller gROM by demographic characteristics. During follow-up (mean 45.8 months), both groups had similar improvements, but the C5 palsy rates were higher in the greater gROM group than in the smaller gROM group (71% and 22%, P < 0.05). CONCLUSIONS: Simultaneous circumferential decompression and fixation is an effective surgical option for patients with cervical myelopathy caused by OPLL. A higher rate of postoperative C5 palsy was observed in the patients with greater gROMs after surgery, although all patients presented with similar clinical improvements.