China
Africa
Explore chapters and articles related to this topic
Intervertebral Disk
Published in Verna Wright, Eric L. Radin, Mechanics of Human Joints, 2020
As discussed earlier, disks do not fail or “herniate” in the clinical sense, from compressive loading alone. This is true even with advanced degeneration. Rather, the end plates fail. Through the end plate, disk material can herniate into the vertebral bodies. This is probably the cause of Schmorl’s nodes.
Intervertebral Disc Degeneration in Clinics
Published in Raquel M. Gonçalves, Mário Adolfo Barbosa, Gene and Cell Delivery for Intervertebral Disc Degeneration, 2018
Pedro Santos Silva, Paulo Pereira, Rui Vaz
Degeneration of vertebral body endplates and subchondral bone on MRI was classified into three types (Modic et al. 1988). Modic type I changes are hypointense on T1-weighted and hyperintense on T2-weighted images, and indicate bone marrow edema. These are thought to represent acute changes of the vertebral body and can be related to discogenic back pain (Weishaupt et al. 2001). Type II changes are hyperintense on both T1 and T2 sequences and represent chronic degenerative changes with bone marrow replacement by fat. Modic type III changes are hypointense on both T1 and T2 sequences, indicating sclerotic vertebral endplates. The intervertebral disc can herniate through a disruption in the vertebral body endplates, causing an intravertebral disc herniation (Schmorl nodes).
The Back
Published in Louis Solomon, David Warwick, Selvadurai Nayagam, Apley and Solomon's Concise System of Orthopaedics and Trauma, 2014
Louis Solomon, David Warwick, Selvadurai Nayagam
This is a ‘developmental’ disorder in which there is abnormal ossification (and possibly some fragmentation) of the ring epiphyses that appear on the upper and lower surfaces of each vertebral body in the growing spine. As a consequence these cartilaginous end-plates are weaker than normal and the affected vertebrae in the thoracic spine (which is normally mildly kyphotic) may give way slightly and become wedge shaped. If this happens, the normal kyphosis is exaggerated. In the lumbar spine the compressive forces are more evenly distributed and deformity does not occur. Sometimes there may also be small central herniations of disc material into the vertebral body; these are called Schmorl’s nodes.
Biomechanical comparison of vertebral augmentation and cement discoplasty for the treatment of symptomatic Schmorl’s node: a finite element analysis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Kaiwen Cai, Zhang Zhang, Kefeng Luo, Feng Cao, Bin Lu, Yuanhua Wu, Hongxia Wang, Kai Zhang, Guoqiang Jiang
In 2006, Masala et al. first reported the use of percutaneous vertebroplasty (PVP) for treating symptomatic Schmorl’s nodes (Masala et al. 2006). Soon thereafter, several researchers began experimenting with percutaneous vertebral augmentation (PVA), including PVP and percutaneous kyphoplasty (PKP), to treat this disease. PVA surgery is able to provide rapid pain relief and significant capacity improvement, which is well maintained in long-term follow-up (He et al. 2017; Amoretti et al. 2019; Zhi-Yong et al. 2017; Masala et al. 2014). In 2015, an alternative surgical approach referred to as either percutaneous cement discoplasty (PCD) or percutaneous disc cementoplasty (PDC) was first reported by Varga et al. (2015). This procedure was initially used to treat the disc vacuum phenomenon caused by severe degeneration of the disc, as well as vertical instability syndromes, such as secondary foramen stenosis. More recently, this technique has been introduced in the treatment of symptomatic Schmorl’s nodes, with satisfactory results (Tian et al. 2017, 2019; Kiss et al. 2019). However, the evidences of these two novel technologies have been based on case series reports, with few reports of surgical-related complications. High-quality evidence regarding the safety and efficacy of these methods are therefore lacking due to the small sample sizes and high risk for conclusion bias associated with this type of research. To the best of our knowledge, no controlled studies have investigated the use of either method to date.
Modic changes and its association with other MRI phenotypes in east Anatolian low back pain patients
Published in British Journal of Neurosurgery, 2022
Disc degeneration was graded from 1 to 5 according to the modified Pfirrmann classification18; the total degeneration score was obtained by the summation of individual Pfirrmann scores at each lumbar level. The degree of disc displacement (herniation) was categorized as follows: bulging, protrusion, and extrusion. Schmorl’s nodes (SN) were defined as areas of endplate irregularities where the intervertebral disc protrudes into the adjacent vertebral body.19 Instances of bone sclerosis or hypertrophy extending anterior or posterior to the vertebral body were evaluated as osteophytes. To assess multiple SN and osteophyte occurrences, SNs and osteophytes at each of the 6 vertebral corpuses were evaluated. Disc height was determined by measuring the distance between the upper and lower end plates of the adjacent vertebrae. The disc height was considered normal if it was equal to or greater than the upper disc space. If the measurement of disc level was greater than the upper disc space, a score of 0 was assigned; if the measurement was equivalent to the upper disc space, a score of 1 was assigned; if the measurement of the disc level was less than the upper disc space, a score of 2 was assigned; and if the endplates were closed, a score of 3 was assigned.20,21
Clinically suspected fibrocartilaginous embolism: a case report and literature review
Published in International Journal of Neuroscience, 2022
Wencan Ke, Chao Chen, Shuai Li, Bingjin Wang, Saideng Lu, Cao Yang
In order to summarize the specific clinical features of FCE, we retrospectively reviewed 40 reported cases that were clinically diagnosed as FCE (Table 1) [2, 3, 7–31]. Of the 40 patients, there are 22 men and 18 women (median age, 27.8 years old; range, 6–64 years). Half of the patients were younger than 18 years of age (n = 20; 50%). Most cases (36 of 40; 90%) reported a suspected trigger before symptom onset, such as handstand, heavy lifting, minor motor vehicle accident or exercising. The predominantly affected spinal segment was the thoracic spine (n = 30; 75%). This result is different from a previous study, which reported the cervical spine as the predominantly affected spinal segment [22]. The difference may result from the different criteria for case selection. In our review, all clinically diagnosed cases of FCE survived a follow-up period of at least 6 months. In the previous study, there were 39 biopsy-proven cases of a total 52 patients. It is recognized that when infarcts involve the cervical spine, there is a higher mortality rate. Except for 6 unreported cases, 9 of the remaining 34 patients demonstrated elevated protein levels in the CSF. This suggests a weak association between elevated protein level and infarction. Schmorl nodes are also recognized as a characteristic feature of FCE. Previous literature has indicated that Schmorl nodes are observed in 38% to 79% of the adult population [32]. However, in our review, except for 6 unreported cases, Schmorl nodes were observed in only 29% (n = 9) of the remaining 31 patients. This difference may result from the various mechanisms of FCE. When disc material breaks through the vertebral endplate, Schmorl nodes can be found on CT and/or MRI. MRI is a sensitive method for the evaluation of SCI, but it lacks specificity, because extensive T2-weighted hyperintensity can be observed in different myelopathies. However, MRI can exclude alternative diagnoses, such as hematoma, vascular malformation and space-occupying lesion. Based on our systematic review of the reported cases and previous studies, we proposed three more feasible clinical diagnostic criteria for FCE (Table 2) [3, 22, 32].