Flat panel detector-CT with endovenous injection. Description of a novel technique for obtaining cerebral arteries imaging: Technical note


 
 
 
 
 
410 | Ansari - Lobster claw sign in cervical cord injury 

 

 
 
 
 
 
 

Lobster claw sign: a new sign depicting central cervical 
cord injury at or below that level. Case report 

Ahmed Ansari 

Department of Neurosurgery, Hamdard Institute, Jamia Hamdard, New Delhi, INDIA 

 
Abstract: Traumatic cervical central cord spinal injuries (CSS) are now more readily 
recognized both clinically and on radiolgical scans. In this article, we introduce a lobster 
claw sign due to a particular positioning of spinous process of C2 and C3 with cord 
contusion from C3-C5 following injury. 
Key words: traumatic central cervical cord, lobster claw sign 

 
Introduction 

McKinley found that 9.2% of all spinal cord 
injuries were attributed to central spinal cord 
syndrome.1 When presenting to emergency 
rooms, typically with greater upper vs. lower 
extremity neurological deficits, CSS patients 
first undergo X ray or computed tomography 
(CT) studies to rule out fracture/dislocation, 
and secondarily have MR examinations 
looking for classical central cord contusion 
/edema / hematomas. We present a typical 
sign of lobster claw on plain X ray cervical 
spine with underlying cord contusion on MR. 

Case report 
A 56 year old man with fall of heavy object 

overhead presented to us five days after injury 
with quadriparesis. There was no bowel and 
bladder involvement. Power in his right upper 
limb was 1/5 and 2/5 in left upper limb. 
Bilateral lower limb power was 3/5. CT head 
suggested linear fracture in occipital bone on 
right side reaching till foramen magnum. X ray 

cervical spine lateral view (Figure 1) showed a 
typical appearance of spinous process of C2 
and C3, resembling a lobster claw along with 
degenerative changes. MRI cervical spine 
(Figures 2, 3, 4) was performed which showed 
cord contusion from C3-C5. 

 
Figure 1 - X- ray cervical spine lateral view showing 

the typical lobster claw sign owing to spinous process 
of C2 and C3 



 
 
 
 
 

Romanian Neurosurgery (2016) XXX 3: 410 - 412 | 411 

 

 
 
 
 
 
 

 
Figure 2 - Sagittal MRI showing cord contusion from 

C3- C5 level 
 

 
Figure 3 - Axial MRI at C3-C4 level with cord 

contusion 
 

 
Figure 4 - Axial MRI at C4-C5 level with cord 

contusion 

Discussion 
Nowak et al. considered CSS to be the most 

common type of incomplete spinal cord injury 
that typically occurs following traumatic 
hyperextension events in older patients with 
underlying cervical spondylosis/stenosis. (2) 
Deficits may vary from weakness in the 
hands/forearms with relative sensory 
preservation, to severe quadriparesis (with 
sacral sparing consistent with an incomplete 
injury). 

Li and Dai assessed the stress distribution 
to the cervical cord under different injury 
conditions to better understand the etiology of 
acute CCSs. (3) Histopathologic studies 
typically revealed that CSS occurs due to 
predominant white matter injury. In their 
feline model, cervical cord injuries were 
simulated in hyperextension (pinch force 
anterior (A) or posterior (B); flexion injuries 
(C)), and vertical compression (pinch force 
anterior (D) or posterior (E)). Results were 
analyzed utilizing a representative cross-
section analysis. They attributed upper 
extremity weakness to damage involving the 
corticospinal tracts and motor neurons in the 
anterior horn. 

Schneideret al. originally defined this 
syndrome in 1954, citing the predominant 
hyperextension mechanism in the absence of 
fracture/dislocation following various 
traumatic events (e.g. motor vehicle accidents, 
falls, and diving injuries). His definition 
included the greater upper vs. lower extremity 
motor deficits, the presence of bladder 
dysfunction, and variable sensory below the 
locus of the trauma. His study included a 



 
 
 
 
 
412 | Ansari - Lobster claw sign in cervical cord injury 

 

 
 
 
 
 
 

review of 15 patients who presented with 
minor or major cervical injuries, in patients 
ranging in age from 18 to 85. Most injuries 
were attributed to acute mechanical 
compression attributed to hyperextension, 
resulting in the “pincer compression” of the 
cord between the spondylotic osteophytes 
anteriorly and acute inward buckling of the 
yellow ligament posteriorly. 

Aarabi et al. evaluated traumatic central 
cord syndromes (TCCSs) characterized by 
incomplete spinal cord injuries. (4) In up to 
50% of patients, they are due to 
hyperextension events in those with 
underlying congenital/degenerative spinal 
stenosis. 

Song et al. assessed the clinical/prognostic 
value of dynamic X-rays and MR studies in 23 
patients with CCS without 
fracture/dislocation.5 They evaluated multiple 
X-rays and MR factors including; prevertebral 
hyperintensity (HI), cord compression, 
intramedullary high-signal intensity (IMHSI), 
with/without instability. 

In our patient, we were able to find this new 
sign on plain X-ray, namely “lobster claw”, 
which we think should raise the suspicion of 
central cervical cord injury. This, all the more 
signifies the importance of plain radiology at 
small centres which are not equipped enough 
with advanced scanners. 

Although, "lobster-claw” is a classic sign in 
uroradiology, (6, 7) it is a sign of papillary 

necrosis and it is due to complete sloughing of 
the central papilla with distortion of a residual 
“claw-shaped” calyx. 

We clearly understand more cases are 
needed to validate this sign “lobster claw” in 
neuro radiology. 
 
Correspondence 
Dr. Ahmed Ansari 
ahmed.ansari2@gmail.com 
+91-9997456045 

References 
1.McKinley W, Santos K, Meade M, Brooke K. Incidence 
and outcomes of spinal cord injury clinical syndromes. J 
Spinal Cord Med. 2007;30:215–24.  
2.Nowak DD, Lee JK, Gelb DE, Poelstra KA, Ludwig SC. 
Central cord syndrome. J Am Acad Orthop Surg. 
2009;17:756–65.  
3.Li XF, Dai LY. Acute central cord syndrome: Injury 
mechanisms and stress features.Spine (Phila Pa 1976) 
2010;35:E955–64. 
4.Aarabi B, Koltz M, Ibrahimi D. Hyperextension cervical 
spine injuries and traumatic central cord syndrome. 
Neurosurg Focus. 2008;25:E9.  
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