a 71-year - old man presented at our institution 's emergency department with worsening quadriparesis . prior to this presentation , he had a 2-week history of upper respiratory tract infection as well as neck pain , which were both treated symptomatically .
one week before admission , he began experiencing progressive weakness in all four limbs . on presentation
upon examination the left side had grade 0 power , and the right side was slightly stronger with grade 2 power in both upper and lower limbs .
blood investigations showed a total white count of 16,500/mm , c - reactive protein of 73 , and erythrocyte sedimentation rate was 100 mm / h .
cerebrospinal fluid analysis showed low glucose and high protein levels but failed to grow any organism .
imaging included plain radiographs , cervical spine computerized tomography ( ct ) , brain and cervical spine magnetic resonance imaging ( mri ) .
ct scans were suggestive of erosive lesions in the left - sided c1c2 and c2c3 facetal joints .
mri showed evidence of an epidural abscess on the left side abutting the cervicomedullary junction as well as osteomyelitis and myositis of the structures around the atlantoaxial joint ( figs . 1 
 2 
 3 
 4 
 5 ) .
there were also radiological features suggestive of meningitis and pyogenic ventriculitis with no hydrocephalus or brain abscesses . 

sagittal sections of magnetic resonance imaging ( t2-weighted ) showing extension of the abscess from c0c3 . 

axial section of magnetic resonance imaging ( t2-weighted ) at c1c2 level showing a left - sided hyperintense cervical cord collection . 

sagittal sections of the magnetic resonance imaging ( t1-weighted ) showing extension of the abscess from c0c3 . 

sagittal sections of the magnetic resonance imaging ( contrast enhanced ) showing extension of the abscess from c0c3 . 

contrast - enhanced axial images showing ring enhancement of the collection . in view of the radiological findings and clinical deterioration ,
the posterior arch of c1 was drilled and removed while protecting the extradural portion of the vertebral artery .
the epidural space did not have an abscess , but there were congested epidural veins . at this stage ,
an intradural abscess was suspected , and the dura was opened on the left side with stay sutures ; the left c1 nerve root was cut to get a window to decompress the abscess cavity ( fig .
care was taken to identify and retract the intramural portion of vertebral artery and the spinal part of the accessory nerve .
dissection was limited on the anterior aspect due to proximity of the anterior spinal artery .
durotomy was closed with ethilon 50 ( johnson & johnson , somerville , nj ) and sealed with tissue glue . 

cultures grew methicillin - susceptible staphylococcus aureus , which was treated with an extended course of intravenous cloxacillin .
the patient subsequently recovered urinary bladder and bowel function , and on the latest follow - up was noted to have grade 5 power on the left side of the body .
a 71-year - old man presented at our institution 's emergency department with worsening quadriparesis . prior to this presentation , he had a 2-week history of upper respiratory tract infection as well as neck pain , which were both treated symptomatically .
one week before admission , he began experiencing progressive weakness in all four limbs . on presentation
upon examination the left side had grade 0 power , and the right side was slightly stronger with grade 2 power in both upper and lower limbs .
blood investigations showed a total white count of 16,500/mm , c - reactive protein of 73 , and erythrocyte sedimentation rate was 100 mm / h .
cerebrospinal fluid analysis showed low glucose and high protein levels but failed to grow any organism .
imaging included plain radiographs , cervical spine computerized tomography ( ct ) , brain and cervical spine magnetic resonance imaging ( mri ) .
ct scans were suggestive of erosive lesions in the left - sided c1c2 and c2c3 facetal joints .
mri showed evidence of an epidural abscess on the left side abutting the cervicomedullary junction as well as osteomyelitis and myositis of the structures around the atlantoaxial joint ( figs . 1 
 2 
 3 
 4 
 5 ) .
there were also radiological features suggestive of meningitis and pyogenic ventriculitis with no hydrocephalus or brain abscesses . 

sagittal sections of magnetic resonance imaging ( t2-weighted ) showing extension of the abscess from c0c3 . 

axial section of magnetic resonance imaging ( t2-weighted ) at c1c2 level showing a left - sided hyperintense cervical cord collection . 

sagittal sections of the magnetic resonance imaging ( t1-weighted ) showing extension of the abscess from c0c3 . 

sagittal sections of the magnetic resonance imaging ( contrast enhanced ) showing extension of the abscess from c0c3 . 

in view of the radiological findings and clinical deterioration , the decision was made for surgical intervention .
the posterior arch of c1 was drilled and removed while protecting the extradural portion of the vertebral artery .
the epidural space did not have an abscess , but there were congested epidural veins . at this stage ,
an intradural abscess was suspected , and the dura was opened on the left side with stay sutures ; the left c1 nerve root was cut to get a window to decompress the abscess cavity ( fig .
care was taken to identify and retract the intramural portion of vertebral artery and the spinal part of the accessory nerve .
dissection was limited on the anterior aspect due to proximity of the anterior spinal artery .
durotomy was closed with ethilon 50 ( johnson & johnson , somerville , nj ) and sealed with tissue glue . 

cultures grew methicillin - susceptible staphylococcus aureus , which was treated with an extended course of intravenous cloxacillin .
the patient subsequently recovered urinary bladder and bowel function , and on the latest follow - up was noted to have grade 5 power on the left side of the body .
spinal cord dural anatomy and blood flow patterns unlike those of the brain are not conducive to intradural infections .
absence of dural sinuses , width of the epidural space , and centripetal direction of blood flow in the spinal vasculature all contribute toward the low incidence of these abscesses within the spinal dura.5 to date , only 65 cases of ssa have been reported since sittig 's first described case in 1927.2 
 6 only nine of these cases were primary cervical spine collections with no thoracic or lumbar involvement ( table 1).1 
 2 
 3 
 4 
 7 
 8 
 9 
 10 
 11 
  abbreviations : c , cervical ; e. coli , escherichia coli ; ivda , intravenous drug abuse ; lp , lumbar puncture ; s. aureus , staphylococcus aureus ; ? , data not available ; + , mild recovery ; + + , moderate recovery ; + + + , full recovery .
hematogenous spread from the respiratory tract is the most common etiology followed by contiguous spread from adjacent infections.1 congenital dermal sinus or other congenital conditions with open dural defects may also result in intradural collections .
recent reports have pointed toward iatrogenic causes , such as lumbar puncture , injection of a local anesthetic agent , and discography.12 intravenous drug abuse also appears to be a major risk factor , especially in the cervical spine where 3 of 10 patients were drug abusers ( table 1 ) .
the proposed etiology in our patient was a possible community - acquired respiratory tract infection complicated by meningitis causing bacteria seeding beyond the dura resulting in an intradural collection .
culture growth of s. aureus from the surgery specimen was not unexpected as s. aureus is the most commonly involved pathogen.1 
 2 
 3 
 4 
  clinically and radiologically it is difficult to distinguish epidural and intradural abscesses.3 
 4 
 13 like their more common epidural counterpart , suspicion of ssa should be aroused when a febrile patient with back or neck pain reports a recent history of infection .
levy et al described a characteristic triad of fever , neck or back pain , and signs of cord compression , which was present in 18 of their 47 reviewed cases of intradural spine collections.3 this triad was also manifested by our patient upon presentation .
typical mri findings of an intradural spinal abscess have been well described.4 
 13 in t1-weighted images , the intradural lesion is usually isointense with the cord .
on t2-weighted images , the contents appear hyperintense and well demarcated from the other intradural contents . on gadolinium enhancement , a typical ring - enhancing lesion
is seen in the setting of an abscess.4 
 13 however , an epidural abscess may also have some of these characteristic features and therefore diagnosis purely on imaging can be misleading . in our case , it was only after an intraoperative durotomy that the true location of the abscess was revealed .
surgical drainage , together with systemic antibiotics , is the treatment of choice.1 
 2 
 3 without intervention , patients can develop significant neurological deficit below the lesion , and surgery performed after this stage may not reverse the deficits .
surgical decompression and washout were performed among all the cervical intradural abscess cases reported to date , with a majority showing good recovery ( table 1 ) .
postsurgery he improved considerably , and the only deficit that remained was a mild right - sided hemiporasis .
he is able to walk independently with the help of a walking stick within 6 months after surgery .
cervical intradural abscess is an extremely rare but a well - described entity that requires prompt surgical intervention
. it can be clinically and radiologically indistinguishable from the more commonly occurring epidural collection .
thus if an exploration of a suspected epidural abscess with progressive neurological deficits is performed , one must always be aware of the possibility of an intradural or a combination abscess and therefore keep a low threshold for performing a durotomy to look for a subdural collection that maybe mimicking the epidural abscess .
 intradural spinal cord abscesses especially in the cervical spine are a rare occurrence . 
 we report a rare presentation of an intradural extramedullary abscess at the atlantoaxial level , initially misdiagnosed as an epidural collection . 
 the patient presented with worsening quadriparesis preceded by a 2-week history of upper respiratory tract infection and neck pain . 
 magnetic resonance imaging showed evidence of an epidural abscess on the left side abutting the cervicomedullary junction . 
 we performed occipitocervical fixation and surgical decompression . 
 absence of a suspected epidural abscess led us to consider a durotomy , and an intradural abscess was recognized and drained . 
 presence of an intradural abscess , though extremely rare , must always be considered in suspected spinal epidural collections as radiological and clinical findings are indistinguishable between the two conditions . 
Case Report
History and Examination
Investigations
Management
Discussion
Conclusion