Spinal Epidural Abscess

Other Names

• Spinal Abscess
• Spinal Canal Abscess
• Spinal Epidural Abscess

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Background

• This page discusses the pathophysiology, clinical presentation, diagnosis, and treatment of spinal epidural abscess.

History

• First described by Giovanni Morgagni in 1761

Epidemiology

• Incidence is approximately 2-8 cases out of 10,000 hospital admissions
• Mean age is 57
• Male to Female ratio of 1.66:1
• Diabetes is the most common comorbidity, making up 27% of patients
• Most common organism is Staph Aureus at 63.6%

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Introduction

Pathophysiology

• Involves hematogenous, contiguous, and direct inoculation
  • Hematogenous dissemination is most common and occurs in half of all cases, typically secondary to skin and soft tissue infections, and urinary or respiratory tract infections
  • Contiguous spread comprises 10-30% of cases, typically due to vertebral osteomyelitis
  • Direct inoculation usually results from surgical interventions, LP, and other invasive procedures

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Risk Factors

• Intravenous Drug Use
• Immunocompromised state
• Alcohol Use Disorder
• Cancer
• Recent spinal procedure
• Diabetes

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Differential Diagnosis

Differential Diagnosis

• Discitis
• Osteomyelitis
• Ependymoma
• Spinal stenosis
• Transverse Myelitis
• Spinal cord hematoma
• Meningitis
• Urinary tract infection
• Pyelonephritis
• Cauda Equina Syndrome
• Conus Medullaris Syndrome
• Sciatica
• AAA
• Pancreatitis

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Clinical Features

History

• Fever
• Back Pain
• Neurological Deficits
  • Weakness, sensory deficits, and bladder and bowel dysfunction
• Paralysis

Physical Exam

• Midline spinal tenderness
• Motor weakness in the lower extremities
• Diminished sensation in the lower extremities
• Saddle Anesthesia

Special Tests

• Straight Leg Raise

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Evaluation

Sagittal T2-weighted MRI of the thoracic spine demonstrating a spinal epidural abscess (white arrows) causing anterior displacement and compression of the thecal sac.

Radiographs

• Plain Films
  • Typically nonspecific, may show signs of osteomyelitis, discitis, or structural deformities.
• MRI
  • Gold Standard
  • A hypointense signal on T1, hyperintense signal on T2, and ring enhancement
• CT Scan
  • To be used if MRI is contraindicated. CT with contrast may show signs of bone destruction and abscess formation

Blood Cultures

• Positive cultures in 30-50% of cases
• Most commonly Staph Aureus (including MRSA), Streptococci, and Enterobacter.

CSF Analysis

• CSF may show pleocytosis, increased protein, and low glucose in bacterial infections.

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Classification

• Not applicable

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Management

Nonoperative

• Antibiotics alone may be considered in some early cases but is not the first-line treatment.
• Rarely appropriate to forego surgical intervention

Operative

• Indications include significant neurological deficits and large abscess size.

• Surgical Approach:  
  • Laminectomy: Decompression of the spinal cord by removal of laminae and drainage of abscess.
  • Abscess Drainage: Direct removal of the purulent material.
  • Spinal Stabilization: May be required if there is instability or vertebral involvement.

• Antibiotic Therapy: Broad-spectrum IV antibiotics covering Staphylococcus aureus (including MRSA), Streptococci, and Gram-negative organisms
  • Duration is for 6-8 weeks

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Rehabilitation and Return to Play

Rehabilitation

• Needs to be updated

Return to Play

• Needs to be updated

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Prognosis and Complications

Prognosis

• Depends on timeliness of treatment
  • Early intervention leads to better neurological outcomes, with some recovering to full function
  • Delayed treatment or severe abscess can result in permanent neurological deficiencies or paralysis

Complications

• Paraplegia or quadriplegia.
• Sepsis and multi-organ failure
• Recurrence if there was inadequate drainage or antibiotic non-compliance
• Spinal Deformities: Due to bone destruction or post-surgical complications.

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See Also

• Back Pain Main
• Infectious Disease Main
• Physical Exam Back
• Back Anatomy Main

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