Acute spontaneous cervical disc herniation causing rapidly progressive myelopathy in a patient with comorbid ossified posterior longitudinal ligament: Case report and literature review

Posterior longitudinal ligament and its implications in intradural cervical disc herniation: Case report and review of the literature

BACKGROUND

Intradural disc herniations (IDH) are rare, particularly in the cervical spine, where they account for less than 5% of all discs. Adhesions between the ossified/calcified posterior longitudinal ligament (OPLL), dura, and ossified/calcified disc herniations increase the complexity of resecting these cervical lesions.

CASE DESCRIPTION

A 42-year-old male presented with a rapidly progressive cervical myelopathy over a 2-month period. This was attributed to an ossified/calcified intradural cervical disc herniation in conjunction with OPLL. The anterior cervical discectomy and fusion (ACDF) resulted in a dural defect but there was no cerebrospinal fluid (CSF) fistula as the arachnoid membrane remained intact. Had there been a CSF leak, it would have warranted both wound-peritoneal (WP) and lumbo-peritoneal shunts (LP). The surgeons should have anticipated that a CSF leak would likely occur prior to performing the ACDF, and should have prophylactically prepared and draped the abdomen for a potential WP, followed by a LP shunt. Three months postoperatively, the patient's proprioceptive deficit improved, and he almost completely recovered motor function.

CONCLUSION

Performing an ACDF for resection of an intradural calcified/ossified disc with OPLL often results in both a dural defect and CSF fistula. As the arachnoid membrane rarely remains intact, the spine surgeon should be prepared to immediately perform both a WP shunt, and subsequently, an LP. In this case, following an ACDF, resection of an intradural ossified disc with OPLL resulted in an isolated dural defect without a CSF fistula and did not require no dural repair or shunting procedures.

Spinal cord infarction at the level of ossification of the posterior longitudinal ligament

INTRODUCTION

We report a case of acute tetraplegia, without any trauma or symptoms prior to onset, who presented with ossification of the posterior longitudinal ligament (OPLL) in the cervical spine with concomitant spinal cord infarction.

CASE PRESENTATION

A 64-year-old man with a number of risk factors for vascular disease was admitted to our hospital with progressive motor weakness in the bilateral upper and lower extremities. He had initially felt numbness in his left upper extremity and had no previous neurological symptoms or trauma. The night after the initial symptoms, he developed spastic tetraplegia requiring respiratory support. Computed tomography images of the cervical spine demonstrated the segmental type of OPLL. Spinal cord compression and signal intensity changes were identified at the level of C3/4 on magnetic resonance imaging (MRI). He underwent emergency surgery consisting of posterior decompression with laminoplasty of C3-6. Despite the surgery, the patient's tetraplegia did not improve and he continued to require respirator support. There was still no improvement in his neurological status at 10 days postoperatively, and MRI demonstrated evidence of marked spinal cord infarction.

DISCUSSION

Mechanical compression of spinal arteries by OPLL and pre-existing vascular compromise had a role in the pathogenesis of spinal cord infarction. Chronic spinal compression may be characterized by 3 important factors, namely an uncommonly devastating clinical course, vascular risk factors and persistent findings on MRI, and these might lead to early diagnosis of spinal cord infarction.