Objective To review the research progress of bone morphogenetic protein (BMP) and the liability of ossification of the posterior longitudinal ligament (OPLL). Methods Recent literature concerning BMP and the liability of OPLL was reviewed, analysed, and summarized. Results The single nucleotide polymorphisms (SNPs) of BMP gene may produce a minor cumulative effect and increase individual susceptibility to OPLL. A variety of environmental factors can promote the occurrence and development of OPLL by increasing the expression of BMP gene. Conclusion The SNPs of BMP gene may increase individual susceptibility to OPLL. However, interaction of cumulative effect of the SNPs and environmental factors can promote the liability to OPLL.
ObjectiveTo explore the effect of spinal dural release on the effectiveness of expansive cervical laminoplasty for treating multi-segmental cervical myelopathy with ossification of posterior longitudinal ligament. MethodsA retrospective analysis was made on the clinical data of 32 patients with multi-segmental cervical myelopathy with cervical ossification of posterior longitudinal ligament who underwent expansive cervical laminoplasty and spinal dural release between February 2011 and October 2013 (group A); and 36 patients undergoing simple expansive cervical laminoplasty between January 2010 and January 2011 served as controls (group B). There was no significant difference in gender, age, disease duration, affected segments, combined internal disease, preoperative cervical curvature, Japanese Orthopaedic Association (JOA) score, and visual analogue scale (VAS) score between 2 groups (P>0.05). Postoperative JOA score and improvement rate, VAS score, posterior displacement of the spinal cord, and the change of cervical curvature were compared between 2 groups. ResultsSpinal dural tear occurred in 3 cases (2 cases in group A and 1 case in group B) during operation. Cerebrospinal fluid leakage occurred in 3 cases (2 cases in group A and 1 case in group B) after operation. The patients were followed up 12-46 months (mean, 18.7 months). At last follow-up, the JOA score and VAS score were significantly improved in 2 groups when compared with preoperative scores (P<0.05). JOA score and improvement rate of group A were significantly higher than those of group B (P<0.05), but VAS score of group A was significantly lower than that of group B (P<0.05). At last follow-up, no significant difference in cervical curvature was found between 2 groups (P>0.05); posterior displacement of the spinal cord of group A was significantly larger than that of group B (P<0.05). No reclosed open-door was observed during follow-up. ConclusionFor patients with multi-segmental cervical myelopathy with ossification of posterior longitudinal ligament, full spinal dural release during expansive cervical laminoplasty can increase the posterior displacement of spinal cord, and significantly improve the effectiveness.
ObjectiveTo systematically review the efficacy and safety of the anterior and posterior approach for the treatment in ossification of the posterior longitudinal ligament (OPLL) of the cervical spine.MethodsAn electronical search was conducted in PubMed, EMbase, The Cochrane Library, Web of Science, WanFang Data and CNKI from inception to December 2016 to collect studies which compared the anterior cervical approach with posterior approach for OPLL. Two reviewers independently screened literature, extracted data and assessed the risk bias of included studies and then RevMan 5.3 software was used to perform meta-analysis.ResultsA total of 20 studies involving 1 263 patients were included. The results of meta-analysis showed that: compared with the posterior approach group, the anterior approach group had higher postoperative JOA score (MD=0.98, 95%CI 0.52 to 1.44, P<0.000 1), higher improvement (MD=12.18, 95% CI 6.65 to 17.71, P<0.000 1), higher re-operation rate (OR=3.21, 95%CI 1.70 to 6.08, P=0.000 3), longer operation time (MD=53.43, 95%CI 12.77 to 94.09, P=0.01) and more bleeding (MD=122.88, 95%CI 39.56 to 206.20, P=0.004), respectively. There was no significant difference in the incidence of complications between two groups (OR=1.49, 95%CI 0.88 to 2.51, P=0.14).ConclusionThe anterior approach for the treatment in OPLL of the cervical spine can achieve better postoperative neurological improvement and lower neurological deterioration, while the posterior approach for the treatment in OPLL has lower re-operation rate, less blood loss and shorter operation time. The incidence of complications between two groups is similar. Due to limited quality and quantity of the included studies, more high quality studies are needed to verify above conclusion.
Objective To investigate the microscope-assisted anterior cervical surgery and traditional open surgery for the treatment of cervical myelopathy with ossification of the posterior longitudinal ligament (OPLL). Methods Retrospective selection of patients with OPLL who underwent microscope-assisted and traditional open anterior cervical surgery in West China (Airport) Hospital Sichuan University were selected between January 2016 and August 2020. The patients who underwent traditional open anterior cervical surgery between January 2016 and August 2018 were classified as the conventional group, and the patients who underwent microscope-assisted anterior cervical surgery between September 2018 and August 2020 were classified as the microscope group. The baseline characteristics, operative time, intraoperative blood loss, length of hospital stay, Visual Analogue Scale (VAS) of pain before and after surgery, and surgical complications were collected. Neurological function was assessed using the Japanese Orthopaedic Association (JOA) score. Result A total of 46 patients were included. There were 24 cases in the conventional group and 22 cases in the microscope group. There was no significant difference in baseline characteristics between the two groups (P>0.05). The operation time, intraoperative blood loss and length of hospital stay in the microscope group were lower than those in the conventional group (P<0.001). There was no significant difference in VSA score and JOA score between the two groups before operation (P>0.05). There were statistically significant differences in VAS score and JOA score between the two groups 18 months after operation (P<0.001). The comparison of VAS score and JOA score in the two groups before and after operation showed that there was a statistically significant difference between 18 months after operation and before operation (P<0.05). In the microscope group, the average improvement rate of neurological function [(79.90±16.67)% vs. (58.12±17.47)%, t=4.317, P<0.001], excellent and good rate [95.45% (21/22) vs. 66.67% (16/24), χ2=4.354, P=0.037] were higher than those in the conventional group. The total number of complications in the microscope group was lower than that in the conventional group (P=0.024). Conclusion Compared with the traditional open anterior cervical surgery, the microscope-assisted anterior cervical surgery for OPLL can reduce intraoperative blood loss and length of hospital stay, reduce the incidence of postoperative complications.
Objective To evaluate the application of surgical strategies for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) involving the C2 segment. Methods The literature about the surgery for cervical OPLL involving C2 segment was reviewed, and the indications, advantages, and disadvantages of surgery were summarized. Results For cervical OPLL involving the C2 segments, laminectomy is suitable for patients with OPLL involving multiple segments, often combined with screw fixation, and has the advantages of adequate decompression and restoration of cervical curvature, with the disadvantages of loss of cervical fixed segmental mobility. Canal-expansive laminoplasty is suitable for patients with positive K-line and has the advantages of simple operation and preservation of cervical segmental mobility, and the disadvantages include progression of ossification, axial symptoms, and fracture of the portal axis. Dome-like laminoplasty is suitable for patients without kyphosis/cervical instability and with negative R-line, and can reduce the occurrence of axial symptoms, with the disadvantage of limited decompression. The Shelter technique is suitable for patients with single/double segments and canal encroachment >50% and allows for direct decompression, but is technically demanding and involves risk of dural tear and nerve injury. Double-dome laminoplasty is suitable for patients without kyphosis/cervical instability. Its advantages are the reduction of damage to the cervical semispinal muscles and attachment points and maintenance of cervical curvature, but there is progress in postoperative ossification. Conclusion OPLL involving the C2 segment is a complex subtype of cervical OPLL, which is mainly treated through posterior surgery. However, the degree of spinal cord floatation is limited, and with the progress of ossification, the long-term effectiveness is poor. More research is needed to address the etiology of OPLL and to establish a systematic treatment strategy for cervical OPLL involving the C2 segment.
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 C2-7 Cobb 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 C2-7 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 C2-7 Cobb 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 C2-7 Cobb 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.
Objective To explore the safety and effectiveness of multisegmental thoracic ossification of posterior longitudinal ligament (T-OPLL) treated by laminectomy, posterior longitudinal ligament ossification block release combined with dekyphosis orthopedic surgery using ultrasonic bone scalpel system. Methods The clinical data of 8 patients with multisegmental T-OPLL treated with laminectomy, posterior longitudinal ligament ossification block release combined with dekyphosis orthopedic surgery using ultrasonic bone scalpel system between January 2020 and April 2023 was retrospectively analyzed. There were 3 males and 5 females; the age ranged from 41 to 67 years, with a mean of 57.1 years. The disease duration ranged from 3 to 74 months, with a mean of 33.4 months. Symptoms were progressive numbness and weakness of both lower limbs, unsteady walking, chest and back pain in 3 cases, and urinary and bowel dysfunction in 5 cases; 7 cases showed increased muscle strength of the lower limbs, hyperreflexia of the tendons, and a positive Babinski sign, and 1 case showed decreased muscle strength of the lower limbs, decreased skin sensation, decreased knee and Achilles tendon reflexes, and a negative pathologic sign. Multisegmental posterior longitudinal ligament ossification of thoracic spine was found in 8 cases, with 4-8 segments of ossification, and in 5 cases with multisegmental ossification of the ligamentum flavum. The preoperative Japanese Orthopaedic Association (JOA) thoracic spinal function score was 4.3±0.9, the visual analogue scale (VAS) score was 6.9±1.0, and the the kyphotic Cobb angle of the stenosis segment was (34.62±10.76)°. The operation time, intraoperative blood loss, and complications were recorded. VAS score was used to evaluate the back pain, JOA score was used to evaluate the thoracic spinal cord function and the JOA improvement rate was calculated, and the kyphotic Cobb angle of the stenosis segment was measured and the Cobb angle improvement rate was calculated. Results The operation time ranged from 210 to 340 minutes, with a mean of 271.62 minutes; intraoperative blood loss ranged from 900 to 2 100 mL, with a mean of 1 458.75 mL; the number of resected vertebral plates ranged from 4 to 8, with a mean of 6.1; dural tears and cerebrospinal fluid leakage occurred in 3 cases, and the incisions healed by first intention. All 8 cases were followed up 12-26 months, with a mean of 18.3 months. There was no complication such as loosening of internal fixator, breakage of screws and rods, and no significant progress of ossification. At last follow-up, the VAS score was 1.4±0.7, the JOA thoracic spinal function score was 9.8±0.7, and the the kyphotic Cobb angle of the stenosis segment was (22.12±8.28)°, all of which significantly improved when compared with preoperative ones (t=11.887, P<0.001; t=13.015, P<0.001; t=7.395, P<0.001). The JOA improvement rate was 81.06%±10.93%, of which 5 cases were rated as excellent and 3 cases as good; the Cobb angle improvement rate was 36.51%±14.20%. Conclusion Laminectomy, posterior longitudinal ligament ossification block release combined with dekyphosis orthopedic surgery using ultrasonic bone scalpel system is a safe, effective, and simple method for the treatment of multisegmental T-OPLL, which is a feasible option.