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British Journal of Neurosurgery, February 2012; 26(1): 120–122

© 2012 The Neurosurgical Foundation

ISSN: 0268-8697 print / ISSN 1360-046X online

DOI: 10.3109/02688697.2011.591853

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

Oluwaseun Sobowale 1 , Calvin Soh 2 , Amit Herwadkar 2 , James Sellu 3 & Konstantina Karabatsou 1

1 Department of Neurosurgery, Greater Manchester Neurosciences Centre, Salford Royal Hospital, Salford, Greater Manchester, UK,

2 Department of Neuroradiology, Salford Royal Hospital, Salford, Greater Manchester, UK, 3 School of Medicine, University of

Manchester, Stopford Building, Oxford Road, Manchester, UK

Correspondence: Oluwaseun Sobowale, Department of Neurosurgery, Greater Manchester Neurosciences Centre, Salford Royal Hospital, Salford, Greater

Manchester, UK. E-mail: seun.s@doctors.org.uk

Received for publication 1 March 2011; accepted 15 May 2011

Abstract

Synovial cysts are often incidental fi ndings on spinal imaging.

They can present with back pain and radicular symptoms;

rarely, they can rupture causing an epidural haematoma and

thecal sac compression. We present the fi rst reported case of a

haemorrhagic synovial cyst causing thoracic cord compression,

and review the pertinent literature.

Keywords: haemorrhage ; synovial cyst; spinal cord; thoracic

Clinical details

We report a case of a 67-year-old female who presented

with several months ’ history of severe lower back pain as-

sociated with left leg pain and progressive weakness. She

also described numbness in the left buttock radiating to her

left groin and the anterior surface of her left thigh. Th e pain

caused signifi cant diffi culty walking and sleep disturbance.

She denied having associated sphincter disturbance, weight

loss or any other complaints. Her past medical history in-

cluded hypertension. She was not on any antiplatelet agents

or anticoagulants and had no history of bleeding disorders.

On examination, she had a shuffl ing gait and was limping

on her left leg. She had mild wasting of her left quadriceps,

weakness in her left hip fl exion (MRC 4/5), a left ankle clonus

and downgoing plantars.

MRI scan of her lower thoracic and lumbar spine showed

evidence of a large haemorrhagic dorsal extradural mass le-

sion at T11-12, causing signifi cant narrowing of the spinal

canal and severe compression of the spinal cord (Fig. 1a, b).

Th e patient underwent an uncomplicated T11-T12

laminectomy and removal of a haemorrhagic extradural le-

sion. Intraoperatively, a haemorrhagic encapsulated cystic

lesion was found; the cyst wall was adherent to the dura and

was dissected carefully to avoid dural laceration. Th e lesion

appeared to arise from the T11-T12 facet joint synovium.

Good decompression was achieved and the cyst bed was

cauterised.

Microscopic examination revealed vertebral tissue com-

posed of trabecular bone with intervening normal-appear-

ing bone marrow, fi brous connective tissue, elastic-rich

ligamentous tissue consistent with ligamentum fl avum, skel-

etal muscle and blood clots. Th e ligamentous tissue showed

evidence of degenerative change. Some of the fi brous con-

nective tissue elements also showed evidence of low-grade

chronic infl ammation and one or two foci showed associated

synovium-like tissue potentially forming the wall of the cyst.

Reasonably extensive haemosiderin deposition consistent

with an old haemorrhage was also seen against a background

of variable chronic infl ammation and fi brosis in these frag-

ments. None of the tissue fragments showed evidence of

neoplasia. No granulomatous or acute infl ammation was

seen and no abnormal crystalline deposits were present. Th e

appearances were therefore compatible with those of both

fresh and old haemorrhages against a background of degen-

erative spinal disease and a facet cyst with appearances sug-

gestive of a synovial cyst.

Postoperatively, she made a good recovery and her left

leg pain and weakness almost completely resolved. A post-

operative MRI scan confi rmed good decompression of the

spinal canal with no evidence of synovial cyst residuum (Fig.

2). At her 9-month follow-up appointment, the residual pain

in her thoracic spine had disappeared.

Discussion

Th e term juxtafacet cyst is used to cover the diff erent types

of commonly occurring spinal cysts, which include synovial

cysts and ganglion cysts. 3 Synovial cysts are lined by syn-

ovium, whereas ganglion cysts lack a synovial lining. 3

Synovial cysts of the spine are defi ned as soft tissue

masses, which are located extradurally along the medial

SHORT REPORT

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Haemorrhagic synovial cyst presenting as thoracic cord compression 121

border of a degenerated facet joint, projecting into the spinal

canal. 2 It has been hypothesised that intraspinal synovial

cysts arise as a consequence of degenerative joint disease or

trauma. 1

Intraspinal synovial cysts are associated with degenera-

tion of the facet joint. 1,2 Th eir aetiology is still unclear; how-

ever, reports of intraspinal synovial cysts in the literature

are becoming more frequent due to improved sensitivity of

neuroradiological investigations. 2 MRI is the best imaging

modality for detecting haemorrhagic synovial cysts, although

CT can also depict their defi nite anatomical association to

the facet joint. 2

Haemorrhage into synovial cysts is a rare complication

and may lead to nerve root or thecal sac compression. 2,3

Anticoagulation and trauma have been implicated as aetio-

logical factors for haemorrhage within synovial cysts; howev-

er, most cases are thought to occur without apparent cause. 3 It

is hypothesised that chronic infl ammation leads to the devel-

opment of neoangiogenic vessels and synovial cyst haemor-

rhages are caused by rupture of these fragile vessels. 2,3

Intraspinal synovial cysts are often asymptomatic, but

most commonly present with lower back pain without focal

neurology. 2,3 Bleeding within the cyst or from the cyst into the

spinal canal is accompanied by an increase in volume, which

may lead to acute worsening of pain and radiculopathy due

to compression of the spinal cord and/or nerve roots. 2

Intraspinal synovial cysts most often occur in the lumbar

spine, possibly due to increased motion in that area. 2 Of the

44 previously reported cases of haemorrhagic synovial cysts,

43 were located in the lumbar spine, the most common lo-

cation being L4-L5 followed by L3-L4. 1 Howling and Kessle

stated in their 1997 paper that 80% of synovial cysts are

seen at the L4/5 level, the most mobile segment within the

lumbar spine, and synovial cysts are frequently associated

with lumbar degenerative spondylolisthesis and therefore

instability. Howling and Kessle reported that the remainder

of intraspinal synovial cysts occur at either the L3/4 or L5/

S1 levels. To the best of the authors knowledge, there are no

previous reports of haemorrhagic synovial cysts presenting

as thoracic cord compression.

It has been reported that symptoms from some synovial

cysts may resolve of their own accord with bed rest. 1 Th is is

especially true if the cyst communicates with the facet joint as

this permits decompression of the cord as the infl ammation

settles. 1 However, surgical resection is the mainstay of treat-

ment for haemorrhagic synovial cysts, which by and large

leads to resolution of symptoms. 1,2 Ramieri et al. reported

that in approximately half of the cases they reviewed, sur-

gery was carried out as an emergency because of the sever-

ity of pain and/or the accompanying neurological defi cits.

All previously reported cases of haemorrhagic synovial cysts

Fig. 1. (a) MRI Sagittal of the spine showing a T1-hyperintense heterogeneous mass at the T11-12 level which is compressing and displacing the thecal sac antero-laterally to the right side. Th e lesion is lying adjacent to the left sided facet joint. (b) MRI Axial T2 FSE through T11/12 level shows a left dorsolateral extradural hyperintense mass adjacent to the left facet joint, compressing and displacing the cord ventrolaterally to the right.

Fig. 2. Postoperative MRI scan confi rming good decompression of the spinal canal with no evidence of synovial cyst residuum.

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122 O. Sobowale et al.

have been treated surgically and, as with our case, surgery is

associated with a good outcome.

Conclusion

We present a case of thoracic cord compression caused by a

haemorrhage from an intraspinal synovial cyst. Review of the

literature suggests that the commonest location of synovial

cysts is in the lumbar spine. 2 We propose that haemorrhagic

synovial cyst of the spinal cord should be considered in the

diff erential diagnosis for patients presenting with features of

cord compression and benign-looking features on imaging.

Early diagnosis and surgical decompression are associated

with a favourable outcome. Care should be taken not to de-

stabilise the spine, if possible.

Declaration of interest : Th e authors report no confl icts of

interest. Th e authors alone are responsible for the content

and writing of the paper.

References

Howling SJ, Kessel D. Case report: acute radiculopathy due 1. to a haemorrhagic lumbar synovial cyst. Clin Radiol 1997;52:73 – 4. Ramieri A, Domenicucci M, Seferi A, Paolini S, Petrozza V, 2. Delfi ni R. Lumbar hemorrhagic synovial cysts: diagnosis, pathogenesis, and treatment. Report of 3 cases. Surg Neurol 2006;65:385 – 90. Wait SD, Jones FD, Lonser RR, Lee KS. Symptomatic epidural 3. hematoma caused by lumbar synovial cyst rupture: report of two cases and review of the literature. Neurosurgery 2005;56:E1157; discussion E1157.

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