Haemorrhagic synovial cyst presenting as thoracic cord compression: a case report and review of the literature

Surgical management of facet cysts in the thoracic spine: Radiological manifestations and results of fenestration

BACKGROUND

Facet cysts in the thoracic spine are a rare cause of thoracic myelopathy. We aimed to investigate the clinical/radiological features and surgical results of these lesions.

METHODS

Nine thoracic facet cysts in eight patients (seven men, one woman) were diagnosed based on magnetic resonance imaging (MRI) and computed tomography (CT) with facet arthrography findings and surgically treated. The mean patient age was 71 (59-83) years. The cysts were distributed as follows: one each at T8-9 and T9-10, two each at T1-2 and T11-12, and three at T10-11. The mean follow-up period was 1.8 (1-5) years. Clinical and radiological features were retrospectively investigated, and surgical outcomes were evaluated according to modified Japanese Orthopaedic Association (JOA) scores for thoracic myelopathy (full score: 11).

RESULTS

Neurological examination revealed progressive thoracic transverse myelopathy in all patients with a mean disease duration of 1.2 months (2 weeks-2 months). MRI revealed a total of nine cysts across the eight patients: four in the median region and five in the paramedian portion of the spinal canal. CT revealed degeneration in all involved facet joints. All the cysts were in communication with the neighboring facet joint confirmed by CT facet arthrography. All patients underwent bilateral fenestration, and the cysts were resected with the ligamentum flavum. The mean preoperative and postoperative modified JOA scores were 4.5 and 8.8, respectively. The mean recovery rate was 67.5%. Differences in the degree of local kyphosis were 2° or less between before and after surgery. On histopathology, synovial lining cells were not noted in any case.

CONCLUSIONS

Decompression surgery is recommended for treating progressive myelopathy in patients with cystic lesions. Our study suggests that thoracic facet cyst resection with satisfactory surgical outcomes would be possible through fenestration.

Complete Resolution of a Large Hemorrhagic Lumbar Synovial Cyst Following Spinal Fusion Alone

The authors reported complete regression of a large hemorrhagic lumbar synovial cyst following posterior spinal fusion without direct cystic resection. A 64-year-old woman suffered from sudden onset of the left buttock pain radiating to the left leg after waking up in the morning following the previous history of a minor accident 2 months ago. Magnetic resonance imaging (MRI) of the lumbosacral spine showed a large extradural round mass originating from the left facet joint at the level of L3–L4. The mass was hyperintense on T1-weighted images and hypointense on T2-weighted images, probably compatible with hemorrhagic joint-related cyst. Surgical treatment was chosen for her because of persistent left radicular pain with no responding to medications. The patient underwent decompressive laminectomy, subtotal facetectomy, instrumented fusion, and only tissue biopsy due to severe adherence of the mass and dura. Histopathological examination was consistent with a hemorrhagic synovial cyst. The radicular pain completely disappeared after the surgery. Follow-up MRI of the lumbosacral spine obtained 6 months after the surgery demonstrated complete resolution of the hemorrhagic cyst. Complete resolution of hemorrhagic synovial cyst seems to correlate with subtotal facetectomy, probably resulting in leakage of cyst content and subsequent resorption of the cyst wall. In addition, hematoma within the synovial cyst may resolve spontaneously over time.

Upper Thoracic Spine Synovial Cyst Resulting in Paraplegia Following Transient Hypotension

Development of synovial cysts in the rigid thoracic spine is rare. Additionally, synovial cysts with compression of nerve roots typically cause subacute or chronic radiculopathy. We present a patient who had a new diagnosis of upper thoracic (T1-2) synovial cyst that caused acute paraplegia while hospitalized for therapies and surgical planning. The patient is a 56-year-old male with a history of congestive heart failure secondary to alcoholic cardiomyopathy. He presented with a progressive bilateral lower extremity discoordination, urinary incontinence, and altered perineal sensation. His examination revealed intact strength to bedside assessment, intact rectal tone, but upgoing toes on Babinski testing. Given concern for myelopathy, MRI thoracic spine was obtained and demonstrated large T1-2 synovial cyst causing severe compression with associated T2 signal change within the spinal cord. He underwent expedited cardiac optimization that included resumption of outpatient antihypertensive medications and the addition of a single dose of intravenous diuretic. The patient had subsequent transient hypotension following significant diuresis and developed acute paraplegia in his bilateral lower extremities. Fluids and vasopressors were initiated, and he underwent emergent surgery for decompression and synovial cyst resection. The patient did very well and had normalization of his neurological exam within 24 hours. We present a case of acute paraplegia secondary to hypotension and spinal cord hypoperfusion in a patient with upper thoracic synovial cyst. This is rare pathology with an even more unique presentation. The authors recommend careful perioperative hemodynamic monitoring to help avoid acute worsening in this patient population.

Rapid Neurologic Deterioration due to an Enlarging Thoracic Spine Synovial Cyst: A Case Report

CASE

We present the case of a 69-year-old man arriving to our clinic after a previous outside hospital recommendation of L1-S1 fusion due to degenerative scoliosis. A thoracic spine synovial cyst was identified through magnetic resonance imaging. The patient had rapid progression of his neurologic deficit due to cyst enlargement. We elected to perform cyst decompression and instrumented fusion of the involved thoracic segment. The patient rapidly regained full neurologic function. After the one-year follow-up, he remained asymptomatic with no progression of thoracolumbar degeneration.

CONCLUSIONS

Thoracic spine synovial facet cysts are uncommonly encountered. Decompression alone or decompression and fusion are both viable treatment options depending on the surgeon's assessment of spine stability after decompression. This diagnosis should be considered in patients presenting with unilateral lower extremity upper motor neuron findings.

Sudden Onset of Paraparesis Caused by a Hemorrhagic Thoracic Synovial Cyst

BACKGROUND

Hemorrhage is a rare presentation of spinal synovial cysts, which are usually located in the lumbar spine. They may cause an epidural hematoma and compression of the cauda equina. Infrequently, they may be located in the thoracic spine.

CASE DESCRIPTION

We present a case of sudden onset paraparesis caused by hemorrhage in a synovial cyst at a midthoracic level. Clinical, radiologic, and histologic findings are described.

CONCLUSIONS

This report describes a unique case of hemorrhagic synovial cyst at the mid-thoracic spine. These lesions are rarely located in the cervico-thoracic spine but should be included in the differential diagnosis of myelopathy.