II. Epidemiology

  1. Incidence
    1. Men: 7.3 per 100,000
    2. Women: 0.7 per 100,000
  2. Mean age: 30 to 44 years old (esp. men)

III. Causes: Trauma (70%)

  1. Burn Injury
  2. Fracture (most common)
    1. Tibial diaphysis Fracture is most common cause
    2. Open Fracture does not reduce risk of Compartment Syndrome
  3. Crush injury
  4. Hemorrhage (esp. vascular injury, on Anticoagulants, Bleeding Disorder)
  5. Prolonged application of MAST trousers (PASG)
  6. Snake Bite

IV. Causes: Nin-Trauma (30%)

  1. Deep Vein Thrombosis
  2. Prolonged extremity compression (tight cast or splint)
  3. Blood Flow Restored in previously ischemic limb
  4. IV Contrast Extravasation
  5. Infection
  6. Malignancy
  7. Drug Overdose

V. Pathophysiology: Mechanism

  1. Extremity Trauma increases interstitial tissue pressure (due to factors listed above)
  2. Increased pressure occurs in fixed fascial compartment
  3. Tissue pressure rises above that of capillaries
  4. Blood Flow distal to high tissue pressures is cut off
  5. Ischemic Muscle and tissue become hypoxic and generate acidosis with secondary increased capillary permeability
  6. Further fluid extravasation into compartment further increases pressure
  7. Distal nerve (in first 12 hours) and Muscle (in first 3-4 hours) become ischemic and necrose

VI. Pathophysiology: Compartments

  1. Thigh, Leg or foot
    1. Anterior Compartment (between anterior tibial and fibula)
    2. Lateral Compartment (anterolateral to fibula)
    3. Superficial Posterior Compartment (posterior leg superficial to neurovascular structures)
    4. Deep Posterior Compartment (posterior leg deep to neurovascular structures)
  2. Forearm (3 compartments)
    1. Volar (wrist flexors, Median Nerve and Ulnar Nerve)
    2. Dorsal (wrist extensors, finger extensors)
    3. Mobile wad (Muscle bodies)
  3. Hand (10 compartments)
    1. Hypothenar compartment
    2. Thenar compartment
    3. Adductor pollicis compartment
    4. Four dorsal interossei compartments
    5. Three volar interossei compartments

VII. Risk Factors: Regions

  1. Tibial Shaft Fractures
    1. Compartment Syndrome complicates 3-5% of adult tibial shaft Fractures
    2. Although uncommon <12 years, tibial shaft Fracture accounts for 40% of childhood cases
    3. Malhotra (2015) Injury 46(2): 254-8 +PMID: 24972494 [PubMed]
  2. Other common compartments
    1. Forearm and Hand
  3. Less common areas of Compartment Syndrome
    1. Thigh
    2. Buttock
    3. Upper arm

VIII. Symptoms

  1. Presentation within first 24-48 hours from time of causative event (e.g. injury)
  2. Severe extremity pain out of proportion to injury
    1. This is the only consistent finding in Compartment Syndrome
  3. Paresthesias or Anesthesia to light touch
  4. Mnemonic: "6 Ps" (unreliable in young or non-verbal patients)
    1. Pain
    2. Pressure (pain on palpation)
    3. Paresthesia
    4. Paresis or paralysis (late sign)
    5. Pallor (late sign)
    6. Pulseless (last sign to occur)
  5. Mnemonic: "3 As" (in young children)
    1. Anxiety
    2. Agitation
    3. Analgesic requirement

IX. Signs

  1. Pain or Paresthesias at rest worse with passively Stretching, extension of involved Muscles
    1. Passive finger or toe range of motion
    2. Patient flexes injured extremity to reduce pain
    3. Pain is out of proportion to level of injury and may be refractory to Analgesics
    4. Test Sensitivity 93% (98% if Muscle Weakness is also present)
  2. Decreased Sensation of involved nerves
    1. Vibratory Sensation lost first
  3. Tense extremity swelling or firm compartment
    1. Test Sensitivity <50% for Compartment Syndrome
  4. Less reliable signs of Compartment Syndrome (and consider arterial injury or thrombosis in Trauma)
    1. Distal pulses may be diminished (late sign of Compartment Syndrome)
      1. Occlude collateral circulation when assessing
    2. Distal extremity pallor may be present
  5. Specific extremity neurologic function
    1. Motor Exam
      1. Ulnar Nerve: Claw Hand
      2. Radial Nerve: Wrist Drop
      3. Median Nerve: Cannot make OK Sign
      4. Peroneal Nerve: Foot Drop
        1. Consider Anterior Tibial Compartment Syndrome
    2. Sensory Exam
      1. Radial Nerve: thumb web space
      2. Median Nerve: distal index
      3. Ulnar Nerve: distal pinky
  6. Bunnel Test (stretch test)
    1. Examiner maintains the MCP joints in extension
    2. Actively or passively flex the interphalangeal joints (PIP and DIP joints)
    3. Findings suggestive of Compartment Syndrome
      1. Restricted PIP and DIP joint range of motion when MCP joints are held in extension
      2. PIP and DIP joint range of motion are not restricted when MCP joint is allowed to fall into flexion

X. Diagnosis

  1. Intracompartmental Pressure Monitor (gold standard)
    1. Have a low threshold for checking Compartment Pressures (esp in pain out of proportion)
    2. Normal Compartment Pressures
      1. Adult: 8-10 mmHg
      2. Children: 10-15 mmHg
    3. Diagnostic criteria
      1. Compartment Pressure >30 mmHg OR
      2. Delta-P (Diastolic pressure - Compartment Pressure) <30 mmHg
        1. Delta-P <30 mmHg for >2 hours is highly accurate for Compartment Syndrome
        2. McQueen (2013) J Bone Joint Surg Am 95(8): 673-7 [PubMed]
  2. Near-Infrared Spectroscopy (NIRS, experimental)
    1. Noninvasive spectroscopy (akin to Pulse Oximetry)
    2. Detects hemoglobin Oxygen Saturation at 2-3 cm depth under the skin
    3. Oxygen Saturation is markedly reduced in Compartment Syndrome
    4. Technique limited by body habitus and subcutaneous fat
    5. Cole (2014) J Trauma Treatment S2:003 [PubMed]
      1. https://www.omicsonline.org/open-access/near-infrared-spectroscopy-and-lower-extremity-acute-compartment-syndrome-a-review-of-the-literature-2167-1222.1000S2-003.php?aid=27180

XI. Differential Diagnosis: Acute Extremity Pain out of Proportion

XII. Labs

  1. Serum Chemistry Panel (esp. Renal Function)
  2. Creatine Kinase (CK)
    1. Compartment Syndrome is associated with Rhabdomyolysis in 40% of cases

XIII. Imaging: Differential diagnosis evaluation

  1. Extremity CT arteriography
    1. Evaluate for arterial injury or thrombosis

XIV. Precautions

  1. Irreversible damage occurs in 4-6 hours
  2. Do not wait for pallor or pulselessness
  3. Compartment Syndrome can occur with open Fractures

XV. Management

  1. Consult orthopedic surgery emergently
  2. General Measures
    1. Pain management with Opioid Analgesics
    2. Fluid Resuscitation
    3. Remove any external compression
    4. Reduce Fractures and dislocations
    5. Raise affected limb over heart level
  3. Pressures consistent with Compartment Syndrome
    1. Tissue pressure >30 mmHg
      1. Some use tissue pressure >15 mmHg if symptoms and signs are present
    2. Delta Pressure (Diastolic Pressure - Tissue Pressure) <30 mmHg
  4. Fasciotomy
    1. See Burn Escharotomy
    2. Indications
      1. Tissue pressure exceeds 30-45 mmHg
      2. Tissue pressure within 20 mmHg of Diastolic BP
    3. Technique: Leg
      1. Two longitudinal Incisions (each 15-18 cm long, at least 8 cm apart)
      2. Anterolateral Incision (avoiding superficial peroneal nerve)
      3. Posteromedial Incision (avoiding saphenous vein and saphenous nerve)

XVI. Course

  1. Compartment Syndrome develops hours after injury

XVII. References

  1. Blythe, Gray and Delasobera (2018) Crit Dec Emerg Med 32(7):3-9
  2. Long and Gottlieb in Herbert (2021) EM:Rap 21(6):12-3
  3. Mason, Farah, Inaba in Herbert (2018) EM:Rap 18(6):17
  4. Gardiner (2018) Crit Dec Emerg Med 37(5): 3-14
  5. (1993) ATLS Providers Manual, p. 234-5
  6. Geiderman in Marx (2002) Rosen's Emerg. Med, p. 478-80
  7. Hori (2015) Crit Dec Emerg Med 29(3): 2-7
  8. Warrington (2019) Crit Dec Emerg Med 33(12): 16-17

Images: Related links to external sites (from Bing)

Related Studies