Clinical and prognostic analysis of ossified ligamentum flavum in a Chinese population

Abstract

<jats:p content-type="fine-print"><jats:italic>Object.</jats:italic> The authors performed a retrospective study of clinical and radiological data obtained in 27 Chinese patients with myelopathy induced by ossification of the ligamentum flavum (OLF) who underwent surgery between March 1990 and March 2002. The factors related to surgical outcome of thoracic OLF-induced myelopathy were also assessed.</jats:p> <jats:p content-type="fine-print"><jats:italic>Methods.</jats:italic> The preoperative clinical features and radiological findings were reviewed retrospectively. Preoperative and postoperative neurological status was assessed using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick Scale. The ossified lesions were classified into five types (lateral, extended, enlarged, fused, and tuberous). Multiple linear regression and logistic regression analyses were performed to establish the factors affecting surgical outcome. The patients' chief complaints were lower-limb weakness and gait disturbance (93%), numbness and sensory deficit (89%), and low-back pain (48%). The coexisting pathological entities were disc herniation, canal stenosis, and ossification of posterior longitudinal ligament. The ossified ligamentum flavum was mainly located at the T10–12 (67%) and T1–3 (15%) levels. Symptoms in 26 patients improved but resolved completely in only 14 after surgery. The mean overall JOA score was 5.3 ± 1.9 preoperatively and 7.9 ± 2.3 postoperatively. There is a significant difference between the pre- and postoperative neurological status (p &lt; 0.05) determined by the Student t-test. The recovery rate was 46.3 ± 9.4%. Multiple regression analysis revealed negative correlation between the duration of preoperative symptoms and surgical outcome as well as a positive correlation between the preoperative JOA score and surgical outcome. Logistic regression analysis demonstrated that fecal and/or urinary incontinence, positive patellar and/or ankle clonus, and intramedullary high T<jats:sub>2</jats:sub>-weighted magnetic resonance (MR) imaging signal change had negative effects on the surgical outcome.</jats:p> <jats:p content-type="fine-print"><jats:italic>Conclusions.</jats:italic> The clinical and radiological features of OLF in the Chinese population are similar to those observed in the Japanese population. The duration of preoperative symptoms and JOA score are the most important predictors of the postoperative JOA score and recovery rate. The patients with fecal and/or urinary incontinence, positive patellar and/or ankle clonus, and intramedullary high T<jats:sub>2</jats:sub>-weighted MR imaging signal change were at higher risk of poor outcome after surgery.</jats:p>

Clinical characteristics and surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum: a retrospective analysis of 85 cases

“…13,19,20,22,33,34,56 Preoperative severity of myelopathy was considered as the most important predictor of the postoperative outcome. 19,20,22,56 In accordance with this finding, our research confirmed that preoperative severity of myelopathy was the most important predictor of the highest postoperative JOA score and the lowest percentage RR in multiple linear regression analyses. In addition, the OLF level (middle thoracic), preoperative duration of symptoms and intramedullary signal change on T2WI were also confirmed and significantly correlated with the surgical outcome by multiple regression analysis.…”

“…Thus, when the ligamentum flavum is replaced by a mature bone, its osseous morphology should be V-shaped or a part of V shape on CT images. 12 Although thoracic OLF has been reported in several Asian countries, such as Japan, [11][12][13][14] China 3,4,[15][16][17][18][19] and South Korea, [20][21][22] and also in Caucasian and Caribbean ethnic groups, [23][24][25][26][27][28] extensive studies on thoracic OLF including a large number of patients have not yet been reported in the literature. This is partly due to the relatively low mean prevalence of thoracic OLF, which was reported as 3.8% in China and as 6.2% for Japanese men and 4.8% for Japanese women.…”

Epidemiological survey of ossification of the ligamentum flavum in thoracic spine: CT imaging observation of 993 cases

“…OLF occurs mainly in the Asian population [2][3][4][5][6][7][8] and there are only a few reports in the Caucasian, African, and Arabic racial groups [9][10][11][12][13][14]. OLF is one of the commonest causes of thoracic spinal stenosis and spinal cord compression, which can cause serious neurological symptoms or even paraplegia.…”

Chest Discomfort Secondary to Ossification of the Ligamentum Flavum of the Thoracic Spine: A Case Report

“…Kazuhiko Shiokawa et al introduced a 31-case series of middle-aged men who had symptomatic TOLF lesions at a lower thoracic level in 2001 [9]. Shisheng et al reported on 27 patients who had TOLF [7]. All the above-mentioned patients had symptomatic lesions, and all underwent a total laminectomy.…”

“…OLF, also known as ossification of the yellow ligament, is a pathological condition that affects the ligament and causes a slow and progressive myeloradiculopathy [1,[7][8][9]. TOLF is rare and usually asymptomatic [1].…”