Preoperative Magnetic Resonance Imaging Signal Intensity Classification Is Associated With Clinical Presentation and Surgical Outcomes in Myelopathy Caused by Thoracic Ossification of Ligamentum Flavum: A Multicenter Study

Abstract

Study Design Retrospective Cohort Study Objectives To explore whether classification of the increased signal intensity (ISI) on magnetic resonance imaging (MRI) correlates with clinical presentations and outcomes in symptomatic thoracic ossification of ligamentum flavum (T-OLF) patients. Methods All patients with symptomatic T-OLF who underwent laminectomy at four institutions were reviewed. The ISI on preoperative T2-weighted MRI was divided into 3 groups, Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). Neurological function before surgery and at follow-up was evaluated by the revised Japanese Orthopedic Association (JOA) score. Patients’ demographics, clinical manifestations, and surgical outcomes were compared. Results A total of 94 patients were involved. Preoperative MRI showed 32 patients in Grade 0, 39 patients in Grade 1, and 23 patients in Grade 2. Low extremities numbness, weakness, and clinical signs were less frequent in Grade 0 patients. The grade of ISI was correlated with the duration of symptoms and cord compression. Grade 0 patients had a better preoperative JOA score than those with ISI changes, while Grade 2 patients showed worse neurological recovery, longer duration of operation, more intraoperative blood loss, and a higher incidence of perioperative complications. Conclusion The classification of ISI is an effective parameter for preoperatively assessing cord compression, clinical severity, and surgical outcomes in T-OLF patients. Grade 0 patients have relatively mild neurological impairment but are more likely to be misdiagnosed. Grade 2 indicates the worst clinical impairment and neurological recovery, and implies a risky and challenging surgery.

The Quality of Life of the Patients with Thoracic Ossification of the Ligamentum Flavum after Surgery Using EQ‐5D‐5L

“…However, despite the fact that patients with lower mJOA scores had poorer QoL, patients with the same degree of neurological impairment still showed a significant improvement in QoL after surgery compared with the preoperative period; therefore, we recommend that patients with severe neurological impairment should still be operated aggressively. Whether the neurological impairment is mild or moderate, the QoL is significantly poorer in seniors, and the majority of older patients have difficulties with pain/discomfort, usual activities, and anxiety/depression dimensions, in line with results reported in other studies 1 . A retrospective study by Yamada et al 18 .…”

“…Whether the neurological impairment is mild or moderate, the QoL is significantly poorer in seniors, and the majority of older patients have difficulties with pain/discomfort, usual activities, and anxiety/depression dimensions, in line with results reported in other studies. 1 A retrospective study by Yamada et al . 18 61 patients with TOLF who underwent surgery found no statistically significant association between the previously mentioned factors with poor prognosis.…”

“…The heterotopic ossification of the ligament is known as ossification of the ligamentum flavum (OLF), it is most common in the thoracic spine. The OLF often leads to slowly progressive neurological impairment of the spinal cord, with clinical symptoms such as sensory and motor dysfunction of the lower limbs, positive pathological signs, and hyperreflexia 1 . In 1920, Polgar 2 first reported that thoracic ossification of the ligamentum flavum (TOLF) was closely associated with thoracic myelopathy.…”

“…The OLF often leads to slowly progressive neurological impairment of the spinal cord, with clinical symptoms such as sensory and motor dysfunction of the lower limbs, positive pathological signs, and hyperreflexia. 1 In 1920, Polgar 2 first reported that thoracic ossification of the ligamentum flavum (TOLF) was closely associated with thoracic myelopathy. Previous studies showed that TOLF often occurs in Asian populations, with a prevalence of approximately 36% in the Japanese population 3 and 3.8% in the Chinese population, 2 and it has also been reported in Caucasian, African and Arab populations as well.…”