She improves and is discharged home after a short rehabilitation stay. She then sustains a fall 6 weeks post-operatively and presents with worsening bilateral lower extremity weakness to the point where she is unable to ambulate. You obtain the following CT scan (Fig. 87.4).

After a long discussion of the different treatment options with the patient, you elect to perform a multilevel corpectomy and place the patient in a halo postoperatively. She does well and her strength is improved postoperatively. You obtain a CT scan, shown in Fig. 87.5.

• There is a large C5–C6 herniated nucleus pulposus with severe spinal cord compression at that level as well as a kyphotic deformity at the same level.
  
• There is also a smaller C4–C5 and C6–C7 herniated nucleus pulposus with some cord compression at these two levels.
  
• There is possibly an osteophytic spur or ossified posterior longitudinal ligament (OPLL) at C5–C6

• Most likely diagnosis is cervical spondylotic myelopathy.
  
• Differential diagnosis based on clinical presentation includes the following (mnemonic is “CITTEN DIVA”)¹:
  
  
  
  • Congenital: Chiari malformation, syringomyelia, narrow canal/short pedicles, mucopolysaccharidoses, kyphosis, os odontoideum
    
  • Infection: syphilis (infarction), postviral (herpes, varicella, cytomegalovirus), epidural empyema, vertebral osteomyelitis, acquired immunodeficiency syndrome- [AIDS-] related myelopathy, tuberculosis (Pott disease), parasitic cyst
    
  • Traumatic: spinal shock, epidural hematoma, basal skull trauma, electrical injury, bony fracture
    
  • Tumor: spinal cord tumor (extradural, intradural extramedullary, intramedullary), metastases, carcinomatous meningitis, paraneoplastic syndrome
    
  • Endocrine: Cushing disease, obesity (epidural lipomatosis), acromegaly, Paget disease
    
  • Nutrition/toxins: vitamin B12 deficiency, local anesthetics
    
  • Degenerative: spondylotic myelopathy, OPLL, disk herniation
    
  • Inflammatory: transverse myelitis, multiple sclerosis, Devic syndrome, Guillain-Barre syndrome, amyotrophic lateral sclerosis
    
  • Vascular: spinal epidural, subdural, or subarachnoid hemorrhage, stroke, spinal cord infarction (syphilis, aorta-clamping intraoperatively, hypotension, aortic dissection), arteriovenous malformation, radiation necrosis (causes microvascular occlusion), contrast infusion
    
  • Acquired: herniated disk, OPLL

• Plain radiographs with flexion and extension views
  
• CT scan of the cervical spine
  
• Medical workup
  
  
  
  • Laboratory studies: complete blood count, electrolytes, coagulation profile, type and screen
    
  • Electrocardiogram
    
  • Chest radiograph
    
  • Cardiac echography
    
  • Pulmonary function tests
  
  
• Consultation with Internal Medicine for surgical clearance

• There is OPLL–segmental type at the level of C5–C6

• Anterior approach is described.
  
  
  
  • Anterior cervical diskectomy at C4–C5, C5–C6, C6–C7 may be performed in the standard Smith-Robinson technique.²
    
  • May need to do partial versus complete corpectomy of C5 and/or C6 for resection of OPLL³
    
  • Expect possible dural breach and anticipate its repair
    
  • Fusion with allograft and plate instrumentation
    
  • Use radiographic guidance and microscope
    
  • Use diamond burr on OPLL segment to avoid injuring spinal cord
    
  • May elect to use somatosensory and motor evoked potential monitoring intraoperatively
    
  • May elect to supplement with posterior C4–C7 lateral mass screws
  
  
• Alternatively, a posterior approach may be used (however, this is not the author’s preferred approach, as the pathology is located anteriorly). This may include:
  
  
  
  • Cervical laminoplasty from C3–4 to C7, or
    
  • Cervical laminectomies from C4 to C7 ± lateral mass fusion

• Complications related to surgical technique^4,5
  
  
  
  • Spinal cord edema with central cord syndrome (most likely)
    
  • Cord injury intraoperatively
    
  • Spinal epidural hematoma at surgical site
    
  • Graft dislodgment
    
  • Neck hematoma
  
  
• Complications of anesthesia⁶
  
  
  
  • Spinal cord infarction due to generalized hypotension
    
  • Lingering effect of paralytics or anesthetics
  
  
• Complications related to her medical conditions

• Obtain an urgent MRI of the cervical spine.
  
• Start the patient on steroids (dexamethasone 10 mg intravenously (i.v.) once then 6 mg i.v. every 6 hours or use the high-dose methylprednisolone [Solu-Medrol; Pfizer Pharmaceuticals, New York, NY] spinal cord injury protocol).
  
• Admit to intensive care unit for monitoring.
  
• Avoid hypotension (keep mean arterial pressure >85 mm Hg).
  
• Call the operating room for possible return to explore the wound if a hematoma is suspected.

• MRI shows diffuse cord edema and thickening as well as a cord signal at the level of C5–C6.
  
• Otherwise, no obvious hematoma is seen.
  
• Good alignment and good placement of grafts are visualized.

• Treat medically with steroids.⁴
  
• There are no indications for surgical intervention.

• There is collapse of the construct with extrusion of the anterior instrumentation.
  
• There are compression fractures of C5, C6, and C7 vertebral bodies
  
• Kyphotic deformity is seen again at C5–C6.
  
• Extrusion of the graft at C4–C5 and collapse of the graft at C6–C7 is observed.

• The patient needs urgent surgical intervention (within 24 hours) for cord decompression and repair of the kyphotic deformity.
  
• The extruded hardware also needs to be removed.
  
• The compression fractures of the vertebral bodies need to be repaired and proper alignment needs to be restored.
  
• Obtain further studies preoperatively.
  
  
  
  • Plain radiographs and MRI of the cervical spine
    
  • Preoperative medical clearance from Internal Medicine (urgent)

• Options include⁵
  
  
  
  • Anterior decompression and internal fixation with grafting followed by posterior fixation (lateral mass screws and rods/plates) down to the upper thoracic area, and placement in a cervical collar. (Given the pathology, this remains the author’s preferred approach. However, this was not performed in this case due to patient-related factors and medical issues—these types of issues need to be documented in the patient’s chart very clearly.)
    
  • Anterior decompression and internal fixation with grafting followed by placement of a halo vest (or a sterna-occipital mandibular immobilizer cervicothoracic orthosis if the patient is unable to tolerate the halo, although less ideal)
    
  • Posterior decompression and/or fixation alone is not a good option as the pathology is mainly anterior and the kyphotic deformity is significant.
    
  • Placement of a collar or other soft brace is not an option after anterior fixation alone, as there is involvement of C7 vertebral body, which places the graft at a junctional level.
  
  
• Anterior decompression and fixation would consist of⁷
  
  
  
  • Anterior corpectomy of C5, C6, and C7 vertebral bodies
    
  • Fibular strut graft placement or metallic cage placement
    
  • Use of bone autograft from vertebral bodies to help with arthrodesis
    
  • Anterior instrumentation from C4 to T1 with plate and screws
    
  • Intraoperative adjuncts are as described previously.