Compartment Syndrome

Increased pressure in the enclosed space of the compartments of the limbs, caused by swelling of tissue or increase in fluid, will affect the functions of the muscles and nerves in the compartment

Aetiology

Risk factors

  • Tibial fractures, especially male 10-35 years
  • Open fractures
  • Forearm fractures
  • IVDAs - comatose
  • Anticoagulation and trivial trauma
  • May not involve a fracture e.g. can occur after burns

Pathophysiology

  • Occurs anywhere in skeletal muscle surrounded by fascia, commonly occurs in anterior and deep posterior compartments of leg and volar compartment of forearm
    • 2-15% of patients develop CS following a tibial shaft fracture
  • Results from interstitial pressure increases in closed osseofascial compartments
  • The rising pressure can compress the venous system → congestion within the muscle and secondary ischaemia as oxygenated arterial blood cannot supply the congested muscle
  • Significant muscle damage at compartment pressures >30 mmHg-40 mmHg or within 10-30 mmHg of diastolic
  • If left untreated ischaemic muscle will necrose resulting in fibrotic contracture (Volkmann's ischaemic contracture) and poor function

Clinical presentation

  • 4 P's - (disproportionate) pain, paraethesia, pallor, pulselessness (late sign)
  • Tensely swollen limb, usually tender to touch
  • Pain on passive stretch of muscles in involved compartment

Management

  • If suspected CS, immediately release all dressings/cast to skin
  • Do not elevate
  • Surgery - emergency fasciotomy to relieve pressure
  • Following surgery, the open wound is left open for a few days before seconday closure
    • Many wounds require split skin grafting