The Natural History of Ossification of Yellow Ligament of the Thoracic Spine on MRI: A Population-Based Cohort Study

Abstract

Purpose: To assess the natural history of ossification of yellow ligament (OYL) in the thoracic spine and determine risk factors for progression based on a longitudinal population-based cohort. Methods: A prospective, longitudinal cohort study was performed on a population-based cohort of Southern Chinese volunteers. T2-weighted magnetic resonance imaging (MRI) was used at baseline to identify any OYL and was verified with computed tomography. Follow-up MRI was performed 5 years later. Parameters under study included the size of OYL, levels of involvement, morphology (round, triangular, beak), whether it crossed the midline and any disc degeneration. Results: A total of 114 (6.1%) individuals were identified to have OYL at baseline out of the 1864 individuals. Size progression occurred predominantly at the lower thoracic region. Majority of the new OYL were also in the lower thoracic spine and was associated with higher body mass index (BMI). Smokers were associated with OYL size progression while patients with higher BMI tended to develop new OYL at follow-up. Progression commonly occurred at the lower thoracic levels and regression occurred mostly at the upper thoracic levels. Conclusions: This is the first population-based series addressing the natural history of OYL. Better understanding of the natural history of OYL may provide incentive to introduce preventive measures such as weight reduction and close monitoring for myelopathy development in those at-risk groups for progression. This is especially important for patients with lower thoracic OYL and who are smokers with higher BMI. Level of Evidence: 1 (prognostic study).

Surgical decision-making for ossification of the posterior longitudinal ligament versus other types of degenerative cervical myelopathy: anterior versus posterior approaches

“…Ossification of the posterior longitudinal ligament (OPLL) is also an important pathology. These ossification disorders are more common in Asians and may progress more aggressively [5]. These along with degenerative disc disease constitutes various non-traumatic and degenerative forms of cervical myelopathy and are commonly recognized under the umbrella term of degenerative cervical myelopathy (DCM) [6].…”

Deciphering Obesity-Related Gene Clusters Unearths SOCS3 Immune Infiltrates and 5mC/m6A Modifiers in Ossification of Ligamentum Flavum Pathogenesis

“…As a multifactorial disease, obesity has been considered as an important risk factor associated with the pathogenesis of OLF ( 7 , 8 ). However, obesity-mediated genetic mechanism underlying OLF has not been fully understood.…”

“…To date, genetic, mechanical stress, degeneration, inflammatory, and metabolic factors have been found to be involved in the occurrence and progression of OLF ( 2 – 6 ). Epidemiological studies indicated that a clinical subset of patients with obesity were more susceptible to early-onset or even diffuse OLF ( 7 ). Additionally, concrete evidence has identified obesity as an independent causal factor for the development of OLF in non-elderly adults ( 8 ).…”

High Body Mass Index Is Associated with an Increased Risk of the Onset and Severity of Ossification of Spinal Ligaments

“…OSL typically occurs in Asians, especially the East Asian population, thereby indicating that genetic factors may play a vital role in its onset; however, many environmental factors, such as mechanical stress, metabolic disorders, gender, and age, may also contribute to the occurrence of OSL (5,6). A few researchers have recently begun to focus on the relationship of obesity or body mass index (BMI) with the onset or severity of OSL because the clinical practice has presented the susceptibility of OSL in the obese population, although the results of existing studies are contradictory (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Kobashi et al (6) showed that the BMI of the OPLL group is significantly higher than that of the non-OPLL group in both male (25.8 kg/m 2 vs. 23.3 kg/m 2 , P < 0.05) and female (25.9 kg/m 2 vs. 23.4 kg/m 2 , P < 0.05) individuals.…”