Polar thigh

Background

• Rash-like injury characteristic of extended time in polar environments.
• Form of mechanical abrasion combined with air temperature fluctuations/variations in pockets of air trapped beneath clothing layers
• Generally only seen in polar environments
• Frequently seen in skiers in Arctic environments due to frequent hip extension which stretches clothing overing the thigh, necessity of wearing multiple layers of clothes, and copious amounts of heat locally produced by such exercise

Clinical Features

• Rash: erythematous, often urticarial in appearance
• Frequently on anterior thigh, though can also appear on medial/posterior thigh

Differential Diagnosis

• Allergic reaction
• Infection (e.g. cellulitis, fungal/bacterial/viral)

Cold injuries

• Generalized
  • Accidental hypothermia
  • Therapeutic hypothermia
• Freezing
  • Frostbite
• Non-freezing
  • Trench foot
  • Chilblains (Pernio)
  • Cold panniculitis
  • Cold urticaria
  • Polar thigh

Management

• Topical corticosteroid, e.g. betamethasone valerate 0.025% or 0.05% for non-ulcerated rashes
• Ulceration present
  • Corticosteroid bandage or Granuflex
  • General wound care
  • If severe ulceration, may require plastic surgery consult or transfer to burn unit
• No antibiotics necessary

Prevention

• Long silk shorts or undergarments to prevent mechanical abrasion and improve temperature regulation OR
• Use of emollient or aloe vera

Disposition

• Discharge
• If behavioral modifications are not taken, existing polar thigh can progress to frank ulceration.

See Also

• Frostbite

References

• Rhodes, M & Sorenson, HC. Polar Medicine. In: Auerbach, PS,Auerbach's Wilderness Medicine. 7th ed. Elsevier; 2017.
• <https://www-clinicalkey-com.ezproxy2.umc.edu/#!/content/book/3-s2.0-B9780323359429000115>