記住我
Click on image for details.
CASE REPORT
Year : 2022 | Volume
: 70
| Issue : 8 | Page : 306-309
‘White Cord Syndrome’: A Rare Catastrophic Complication Following Anterior Cervical Discectomy and Fusion
Nishant Goyal1, Jitender Chaturvedi1, Pankaj Kandwal2, Priyanka Gupta3, Ashutosh Kaushal3, Mritunjai Kumar4
1 Department of Neurosurgery, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
2 Department of Orthopedics, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
3 Department of Anesthesiology, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
4 Department of Neurology, All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
Correspondence Address:
Nishant Goyal
Department of Neurosurgery, All India Institute of Medical Sciences, Veerbhadra Road, Rishikesh, Uttarakhand - 249 203
India
Source of Support: None, Conflict of Interest: None
CheckDOI: 10.4103/0028-3886.360940
Background: 'White-cord syndrome' is an extremely rare entity following decompression of cervical cord in which post-operative reperfusion injury results in worsening of patient's neurology and MRI reveals signal changes in spinal cord in absence of cord compression. We wish to report a case of 'white-cord syndrome' following a 'routine' ACDF.
Case Description: A 39-year-old woman with paresthesias and spastic quadriparesis was found to have C5-C6 PIVD on MRI. ACDF was performed at C5-C6, after which worsening of quadriparesis was noted, for which intravenous high-dose steroids were started. An urgent MRI was done, which revealed findings of white-cord syndrome, without compression on underlying cord. With conservative management, her ASIA grade improved from C to D and the features of white-cord syndrome disappeared on follow-up imaging.
Conclusion: It is important for surgeons and patients to be aware of this rare but potentially catastrophic entity as this needs to be discussed while taking consent for surgery.
Keywords: 'White cord syndrome', anterior cervical discectomy and fusion, cervical disc prolapse, complication
Key Message: White cord syndrome can be a catastrophic complication following anterior cervical discectomy and fusion. The prognosis is variable with various patients showing partial recovery.
Anterior cervical discectomy and fusion (ACDF) is generally considered a 'straight forward routine' procedure. Therefore, major neurological deficit following this surgery can be devastating for both patient as well as surgeon. Differential diagnoses for such a complication include incomplete decompression of disc or posterior longitudinal ligament (PLL); epidural haematoma; cord edema from intra-operative manipulation, reperfusion injury or vascular compromise/ischaemia. Urgent MRI is warranted to rule out compressive pathology.[1]'White cord syndrome' is a rare entity following decompression of cervical cord in which post-operative reperfusion injury results in worsening of patient's neurology and Magnetic Resonance Imaging (MRI) reveals hyper-intense signal in spinal cord on T2-weighted images without cord compression.[2],[9],[10]
Authors wish to describe the case of a 39-year-old lady who underwent a seemingly routine ACDF for C5-C6 prolapsed intervertebral disc, but developed transient worsening of power due to 'white cord syndrome'.
Case Report
A 39-year-old lady presented with history of sudden onset electric shock-like-sensation which started from neck down to upper and lower limbs 6 months back while trying to lift a box placed overhead in kitchen. Three months after this incident, she noticed paresthesias, tightness and weakness in all four limbs. At presentation, she was able to walk without support, but she used to have frequent falls due to increased tightness in her lower limbs. There were no bowel-bladder complaints.She was a known diabetic, well-controlled on diet. On examination, tone in bilateral lower limbs was increased and power was 4/5 in elbows, wrists, hips, knees and ankles bilaterally. Hand grip was 60-70% bilaterally. Deep tendon reflexes were 3+ in bilateral knees and ankles and plantars were extensor bilaterally. A diagnosis of cervical myelopathy was made and Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scan of cervical spine were advised.
MRI revealed prolapsed inter-vertebral disc at C5-C6 and CT scan revealed loss of cervical lordosis [Figure 1]. Therefore, the patient was planned for anterior cervical discectomy and fusion using autologous graft. Intra-operatively, dural sac was seen to be pulsating after discectomy and the intra-operative X-ray revealed well-placed graft [Figure 2]a. However, in the immediate post-operative period, the patient developed worsening of power in all four limbs. Power in right lower limb became 1/5 and in the left lower limb, it was 2/5. Hand grip deteriorated to 20% bilaterally. Spasticity worsened in both lower limbs to modified Ashworth scale 3. American Spinal Injury Association (ASIA) grade at this stage was C. She was administered 8 milligrams of dexamethasone and urgent CT and MRI cervical spine were ordered. CT scan confirmed well-placed graft [Figure 2]b and MRI revealed that there was neither a residual disc nor any compression from graft. However, an area of altered signal intensity in spinal cord was seen, which was hypo-intense on T1-weighted and hyper-intense on T2-weighted images [Figure 3]. She was started on baclofen and steroids (8 mg dexamethasone stat followed by 6 mg QID; later tapered-off). At discharge on 16th post-operative day, her power had gradually improved to 4/5 in bilateral elbows and wrists and 3/5 in bilateral lower limbs. Hand-grip had improved to 40% and tone was modified Ashworth grade 1. She was able to void self. At last follow up at 17 months, the patient's power improved to 4+/5 in all four limbs and was ambulating without support. Her ASIA grade at this stage was D. Follow-up MRI revealed complete resolution of the signal changes in the cord [Figure 4].
Figure 1: Pre-operative sagittal (a) and axial (b) images of T2- weighted MRI cervical spine suggestive of prolapsed inter-vertebral disc at C5-C6 level causing significant compression on the underlying cord
Figure 2: Intraoperative X-ray (a) and post-operative CT scan (b) suggestive of well-placed autologous graft at C5-C6 disc space
Figure 3: Post-operative sagittal images of MRI suggestive of T1 hypo-intense (a) and T2 hyper-intense (b) signal changes seen in the cord at C5-C6 level. Well-placed autologous graft is seen in C5-C6 disc space and external compression on the cord is relieved as compared to pre-operative MRI
Figure 4: Follow-up sagittal images of MRI shows complete resolution of cord signal changes. There is collapse of autologous graft seen as well Discussion In the present case, it is plausible that there was chronic compression on the cord due to the massive herniated disc, which produced a large area of cord edema, but the patient had compensated.[11] Over time, her symptoms of radiculomyeopathy would have progressed. Following the surgery, there was an immediate cord expansion within the open canal space following acute decompression of the herniated disc and there was a sudden increase in the blood supply to the previously compressed cord segment. It has been postulated by Chin et al. that sudden cord expansion and reperfusion may result in disruption in blood-spinal cord barrier and trigger a cascade of reperfusion injury resulting in the neurological dysfunction below the involved level. This has been described as 'white cord syndrome'.[2]
The pathophysiology of spinal cord ischemia/reperfusion injury involves oxygen-derived free radical damage,[2],[3] mitochondria-dependant apoptosis, TNF-α production, and specific phospholipid signaling cascades resulting in neuronal injury.[4],[5] It appears that acute and chronic spinal cord ischemic injury may be responsible for passage of blood-borne or neurotrophic substances (specifically TNF-α) through the blood-spinal cord barrier past its saturation point.[4],[5] Decoupling of astrocyte foot processes from endothelial cell surfaces inhibits tight junction function in the blood-cord barrier. This is followed by the disruption of transport systems and ionic buffering allowing worsened reperfusion injury upon decompression of a previously ischemic spinal cord.[2]
There are very few reports of 'white cord syndrome' in published literature [Table 1]. Chin et al. reported the case of a 59-year-old male patient with a large C5-C6 prolapsed cervical disc who underwent anterior cervical decompression and fusion at two levels (C4-C5 and C5-C6). Following the surgery, the patient developed C6 incomplete tetraplegia, for which C5 corpectomy was done along with administration of steroids.[12] Giammalva et al. reported the case of a 64-year-old man affected by C4–6 severe cord compression, who underwent C3–4 and C5–6 ACDF. He developed quadriparesis following surgery and was immediately started on high-dose steroid protocol (NASCIS III).[6] Antwi et al. reported the case of a 68-year-old man affected by C4–6 severe cervical stenosis, who underwent C3–7 posterior decompression surgery. This patient developed hemiparesis after surgery and was immediately started high-dose steroid protocol.[7] All these three patients had partial improvement. Jun et al. reported the case of a 49-year-lady who developed paraplegia following ACDF at C6-C7. The patient recovered completely after she was managed with high-dose steroids along with extensive decompression (laminoplasty at C4-C7).[8] In our patient, there was no compression on the cord after surgery. Therefore, the case was managed with steroids and physiotherapy, following which she had a complete recovery and her neurological condition became better than her pre-operative status. For the management of this entity, one should first decompress the cord surgically if there is any compression. Steroids may have a role in improving the cord function by decreasing edema. The use of hypothermia, cerebrospinal fluid diversion and anti-oxidants has been advised[2] but appears to be doubtful.
Table 1: Summary of ‘white cord syndrome’ cases in the published literatureOf the four cases of 'white-cord syndrome' reported before the present case, a follow-up MRI was available for only the case reported by Chin et al. At last follow-up, this patient showed partial recovery and his follow-up MRI done 16 months after the surgery showed persistent signal changes in the cord. In contrast, the patient reported by us, showed complete resolution of signal changes in the cord at 17 months' follow-up and the patient showed complete clinical recovery. The near complete recovery of the signal change on follow-up MRI is probable evidence that there was no acute mechanical injury during primary surgery. This also indicates that the follow-up MRI findings corroborate with clinical improvement.
Conclusion'White cord syndrome' remains a diagnosis of exclusion where cord compression needs to be ruled out first. Surgeons and patients should be aware of this rare but potentially catastrophic entity as this needs to be discussed while taking consent for surgery. The patients who develop 'white cord syndrome' are expected to make variable degrees of recovery.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
留言 (0)