Anterior Cord Syndrome

Anterior Cord Syndrome (ACS)—also known as Anterior Spinal Artery Syndrome or ventral cord syndrome—is a form of incomplete spinal cord injury characterized by motor paralysis and selective sensory loss.

It results from damage to the anterior two-thirds of the spinal cord, most commonly due to ischemia of the anterior spinal artery. This syndrome is clinically important because it carries a poor prognosis for motor recovery compared to other incomplete cord injuries.

🧬 Anatomy & Pathophysiology

The anterior spinal artery (ASA) supplies:

• Anterior horn cells (motor neurons)
• Corticospinal tracts (motor function)
• Spinothalamic tracts (pain & temperature)

Anterior spinal artery occlusion leads to:

• Ischemia of the anterior two-thirds of the spinal cord
• Infarction of motor and pain pathways

👉 The posterior columns remain intact, as they are supplied by the posterior spinal arteries.

⚠️ Etiology

Anterior cord syndrome can arise from:

🔹 Ischemic Causes (Most Common)

• Aortic pathology (e.g., dissection, aneurysm repair)
• Severe hypotension
• Atherosclerosis or thromboembolism

🔹 Traumatic Causes

• Flexion injuries of the cervical spine
• Burst fractures
• Penetrating trauma (e.g., gunshot wounds)

🔹 Iatrogenic Causes

• Aortic surgery (cross-clamping reduces spinal perfusion)

👉 Overall, vascular compromise is the leading mechanism of the Anterior Cord Syndrome.

Clinical Features

🔸 Motor Findings

• Bilateral paralysis below the lesion (paraplegia or quadriplegia)
• Initial flaccidity → later spasticity

🔸 Sensory Findings

• Loss of:
  • Pain
  • Temperature
• Preserved:
  • Vibration
  • Proprioception

🔸 Autonomic Dysfunction

• Bladder and bowel dysfunction
• Possible sexual dysfunction

👉 This dissociated sensory loss is a hallmark feature.

Diagnosis

📍 Clinical Diagnosis

• Based on neurological examination:
  • Motor paralysis
  • Loss of pain/ temperature
  • Preserved dorsal column function

📍 Imaging

• MRI (gold standard):
  • Detects spinal cord ischemia
  • “Owl’s eyes” sign on axial imaging

📍 Additional Tests

• CSF analysis (rule out infection/demyelination)
• Cardiovascular evaluation (embolic sources)

Treatment

There is no definitive curative therapy, so treatment focuses on:

🔹 Acute Treatment

• Stabilization (airway, breathing, circulation)
• Maintain spinal cord perfusion (optimize blood pressure)
• Treat underlying cause (e.g., vascular pathology)

🔹 Medical Therapy

• Antiplatelet or anticoagulation (if indicated)
• Control of glucose and temperature

🔹 Rehabilitation

• Physical therapy
• Occupational therapy
• Prevention of complications (pressure ulcers, DVT)

👉 Treatment principles are similar to:

• Acute spinal cord injury
• Ischemic vascular conditions

Prognosis

• Generally poor motor recovery
• Some sensory recovery may occur
• Worse outcomes associated with:
  • Severe initial deficits
  • Lack of early improvement
  • High cervical involvement

👉 Among incomplete cord syndromes, Anterior Cord Syndrome has one of the worst prognoses.

Differential Diagnosis

• Central cord syndrome
• Brown-Séquard syndrome
• Posterior cord syndrome
• Transverse myelitis
• Multiple sclerosis

Key Clinical Pearls

• Loss of motor + pain/temperature with preserved proprioception = think anterior cord syndrome
• Most commonly caused by anterior spinal artery ischemia
• MRI is essential for confirmation
• Early recognition is critical but recovery is often limited

Infographic Summery

References & More

1. Sandoval JI, De Jesus O. Anterior Spinal Artery Syndrome. [Updated 2024 Jun 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: Pubmed
2. Khan MM, Munakomi S, Dalal K. Ventral Cord Syndrome. [Updated 2025 Nov 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: Pubmed
3. Egol KA. Handbook of fractures. 6th ed. Philadelphia: Lippincott Williams & Wilkins; 2019.