What is the difference between Saturday night paresthesia and compartment syndrome?

Differences Between Saturday Night Paresthesia and Compartment Syndrome

Saturday night paresthesia is a temporary, benign condition caused by external compression of a nerve, while compartment syndrome is a limb-threatening emergency requiring urgent surgical intervention.

Saturday Night Paresthesia

• Temporary condition caused by external compression of a peripheral nerve, commonly when a person falls asleep in an awkward position or with their limb compressed under their body 1
• Characterized by numbness, tingling, and temporary paresthesia that resolves quickly once the compression is removed 1
• No tissue damage or permanent injury occurs if compression is relieved promptly 1
• No significant swelling, compartment tension, or vascular compromise 1
• Symptoms resolve spontaneously within minutes to hours after removing the compression 1

Compartment Syndrome

• Life-threatening and limb-threatening emergency caused by increased pressure within a closed fascial compartment 2
• Results from internal pressure increases within a muscle compartment that compromises circulation and nerve function 3
• Commonly associated with fractures, crush injuries, burns, vascular injuries, or reperfusion after ischemia 3, 4
• Young men under 35 years with tibial fractures are at particularly high risk 4

Clinical Presentation of Compartment Syndrome

• Pain out of proportion to the injury is the earliest and most reliable warning sign 2
• Pain on passive stretch of the affected muscle compartment is a sensitive early sign 2
• Increasing firmness/tension of the compartment occurs as pressure rises 2
• Progressive symptoms follow a pattern known as the "6 Ps" 3, 2:
  1. Pain (severe, unrelenting)
  2. Pain with passive stretch
  3. Paresthesia (sensory changes)
  4. Pressure/tension in compartment
  5. Paralysis (motor deficits) - late sign
  6. Pulselessness - very late sign

Diagnostic Challenges with Compartment Syndrome

• Clinical signs alone have low sensitivity but high specificity for diagnosis 2
• Severe pain gives only approximately 25% chance of correctly diagnosing compartment syndrome 2
• The presence of both severe pain and pain on passive stretch increases positive predictive value to 68% 2
• Compartment pressure measurements are recommended when diagnosis is in doubt, particularly in obtunded patients 2

Management Differences

• Saturday night paresthesia:

  • Conservative management with position change and observation 1
  • No surgical intervention required 1
  • Complete recovery expected 1

• Compartment syndrome:

  • Surgical emergency requiring immediate fasciotomy 2
  • Delay in treatment leads to tissue necrosis, permanent functional impairment, and potentially renal failure and death 5
  • Positioning the limb at heart level (not elevated) is recommended when compartment syndrome is suspected 2

Critical Distinctions for Clinical Decision-Making

• Duration: Saturday night paresthesia resolves quickly after removing compression, while compartment syndrome worsens over time without intervention 5, 1
• Compartment tension: Absent in Saturday night paresthesia but present in compartment syndrome 2
• Pain quality: Mild to moderate in Saturday night paresthesia versus severe, unrelenting pain in compartment syndrome 2, 5
• Associated injuries: Saturday night paresthesia typically occurs without trauma, while compartment syndrome often follows fractures, crush injuries, or vascular damage 4, 5
• Urgency: Saturday night paresthesia is benign, while compartment syndrome requires emergency surgical consultation for fasciotomy 2, 6

Important Pitfalls to Avoid

• Waiting for late signs of compartment syndrome (pallor, pulselessness, paralysis) can lead to irreversible tissue damage 2
• Relying solely on palpation for diagnosis of compartment syndrome is unreliable 2
• Mistaking early compartment syndrome for a simple "stinger" or temporary nerve compression can lead to devastating consequences 5
• Missing compartment syndrome in patients without fractures, as it can occur with soft tissue injuries alone 2