Thoracic myelopathy caused by calcification of the ligamentum flavum

Abstract

Calcification of the ligamentum flavum (CLF), which is a rare disorder that can potentially cause myelopathy, occurs uncommonly in the thoracic spine. Here, we report a rare case of thoracic myelopathy caused by CLF in a 78-year-old man. Magnetic resonance imaging (MRI) showed posterior spinal cord compression by a hypo-signal intense mass, and computed tomography (CT) revealed CLF and vacuum disc phenomenon at T10/11. After undergoing posterior decompression and instrumented fusion (T9-T12), the patient's gait difficulties improved. The pathogenesis of CLF is largely unknown; however, it involves accumulation of calcium pyrophosphate dehydrate crystals (CPPD), and CLF from CPPD deposition tends to occur within a thickened and hypertrophic ligament. CLF occurs predominantly in the cervical spine and less frequently in the lumbar spine, with few cases involving the thoracolumbar spine. The thoracic spine is characterized by hypomobility; however, the thoraco-lumbar spine has a mobile segment which may potentiate CLF formation. Decompression with fusion surgery can be useful for treating patients with thoraco-lumbar CLF.

Successful treatment of thoracic myelopathy caused by spontaneous spinal epidural hematoma (SSEH) combined with calcification of the ligamentum flavum (CLF) by posterior percutaneous endoscopic surgery (PPES): A case report

“…Until 2021, only eight thoracic CLF cases were reported in English literature, among them, only one exhibited rapid progression while others exhibited slow progressive process ( 4 ) above. All accepted conventional open operations with satisfied results ( 4 ) above.…”

“…Calcification of the ligamentum flavum (CLF) is a rare crystal deposition disease that mainly affects the central portion of the ligamentum flavum (LF) ( 1 , 2 ), and it rarely occurs in the thoracic spine ( 3 ). Spontaneous spinal epidural hematoma (SSEH) is another rare spinal lesion, whose initial presentations are often miscellaneous and atypical and might cause delayed diagnosis and improper treatment ( 4 ).…”

Bilateral translaminar osseous-channel assisted percutaneous full-endoscopic ligamentectomy decompression for thoracic myelopathy due to ossification of the ligamentum flavum: a technical note.

“…As one of the primary causes of thoracic spinal stenosis and TM [ 1 , 18 ], OLF has been shown to have a prevalence of 3.8% to 25% in previous studies [ 19 , 20 ]. With the improvement of diagnostic techniques and the increasing use of CT scanning and MRI, higher prevalence rates of OLF have been confirmed, including a rate as high as 63.9% in Chinese populations [ 21 ].…”

“…Ossification of the ligamentum flavum (OLF) is a well-known cause of thoracic spinal stenosis that has been identified as the primary cause of thoracic myelopathy (TM) [1][2][3]. Particularly in East Asian re-gions, the incidence of thoracic OLF can be as high as 36% in the Japanese population and 63.9% in the Chinese population, although most such cases do not necessarily develop into asymptomatic thoracic canal stenosis and TM [4].…”

“…Once the thoracic OLF is symptomatic, surgical intervention is recommended because it is refractory to conservative treatment [ 5 , 6 ], and this approach also avoids acute myelopathy induced by a minor trauma [ 7 ]. Although several multiple decompression procedures with open approaches or tube techniques, including laminectomy [ 2 ], aminoplasty [ 8 ], with or without instrumented fusion [ 6 ], have been described, the optimal surgical procedure remains controversial [ 1 , 7 ], and surgical outcomes are not always satisfactory [ 2 , 9 ]. The major concerns include greater iatrogenic trauma [ 10 ], a higher risk of neurological deterioration and complications [ 5 , 11 ], and whether instrumentation should be used after the decompression procedure [ 6 , 12 ].…”