Compartment syndrome

Background

  • Most commonly caused by tibia fracture (anterior compartment)

Compartment Syndrome Indications

Pathophysiology

  • Tissue perfusion is difference between diastolic BP and compartment pressure
    • As compartment pressure increases, tissue perfusion decreases

Etiologies

Clinical Features

General Symptoms

  • Compartment is swollen, firm, tender with squeezing
  • Usually develops soon after significant trauma
    • May be delayed up to 48hr after the event

5 P's

  • Classic signs of disruption in arterial flow, not of compartment syndrome
    • Only found once arterial flow has stopped (very late finding)
  1. Pain (early finding)
    • Severe, out of proportion to physical findings
    • Worse with passive movement (muscle extension > increased volume > increased pressure)
    • Often the presenting symptom.
  2. Paresthesia (early finding)
    • Occurs in sensory distribution of affected nerve
  3. Pallor
  4. Paralysis: late finding
  5. Pulselessness: late finding

Lower Leg Specific Syndromes

  • Anterior
    • Nerve: deep fibular (peroneal): sensation of 1st webspace
    • Muscle: tibialis anterior: foot/ankle dorsiflexion
  • Lateral
    • Nerve: superficial fibular (peroneal) nerve: sensation of lateral aspect of lower leg, dorsum of foot
    • Muscle: peroneus longus and brevis: foot plantarflexion
  • Deep posterior
    • Nerve: posterior tibial nerve: sensation of plantar aspect of foot
    • Muscle: tibialis posterior/flexor hallucis longus/flexor digitorum longus: Pain with passive extension of the toes
  • Superficial posterior
    • Nerve: sural cutaneous nerve: sensation of lateral aspect of foot
    • Muscle: gastrocnemius/soleus/plantaris: weakness of plantar flexion
Lower Leg Compartment

Hand

  • Crush injury, with or with out associated fracture
  • Involved compartments: thenar, hypothenar, adductor pollicis, and 4 interossei muscles
  • Diagnosis
    • Clinical, not based on actual compartment pressure
    • Pain
      • Deep, constant, poorly localized, out of proportion to exam
    • "Intrinsic minus" position at rest
      • MCP joint extended with proximal IP joint slightly flexed
    • Pain with passive stretch of involved compartmental muscles
      • Interosseus: performed with MCP joint extended and PIP jionts fully flexed
      • Thenar, hypothenar: performed by extension of MCP joint
    • Tense swelling of affected compartment

Forearm

forearm compartments
  • Associated with supracondylar fracture (peds), distal radius fracture (adults)
  • Compartments
    • Dorsal (highest risk)
    • Volar

Foot

Compartments of the foot
  • Number of compartments is controversial, but at least 4, up to 9
    • Medial, lateral, central, interosseous, adductor
    • Mechanism - crush injuries
    • Other mechanisms - foot surgery, Lisfranc fracture, cast immobilization, prolonged extremity positioning, snake bites, severe ankle sprains with arterial disruption[1]
    • 5-17% of calcaneus fractures result in compartment syndrome
    • Diagnosis
      • Pain out of proprtion
      • Pain worse with passive dorsiflexion (stretching intrinsic musculature of foot); concurrent metatarsal fracture cloud this finding
      • Do not rely on absent pulse or complete anesthesia, which are late findings
      • Measure absolute compartment pressures in insertion sites found here
    • Treatment
      • Elevate extremity to level of heart (above the heart, and there will be reduction of O2 perfusion)
      • SCDs may help decrease interstitial pressure, improve venous return/arterial flow
      • Fasciotomy within 24 hrs of injury if pressures > 30 mmHg

Lumbar Paraspinal

  • Compartment enclosed on the lateral, dorsal and ventral aspects by thoracolumbar fascia and medial aspect by spinous processes and interspinous ligaments
  • Mechanisms
    • Direct trauma
    • Atraumatic mechanism (Heavy weight lifting)
      • Typically males in their 20's and 30's
    • Recent surgery causing compromised blood supply
  • Characteristics
    • Pain of the low back refractory to analgesia
    • Radiation of pain to the groin
    • Tender and tense lumbar paraspinal muscles
    • Loss of normal lumbar lordosis
    • Worsening of pain with hip flexion
    • Concurrent ileus in some cases
  • Diagnosis
    • Elevated CK
    • Elevated compartment pressures
    • Imaging not required
      • If imaging is performed, MRI is the test of choice
      • MRI will demonstrate enhancement of the paraspinal muscles on T2-weighted images
      • CT is less helpful, but can exclude other causes of low-back pain such as fracture
  • Treatment is with emergent fasciotomy and with fluid resuscitation for any concurrent rhabdomyolysis [2]
Magnetic resonance imaging (T1-weighted with gadolinium) showing edema and high signal intensity (arrows) in the region of the left multifidus and longissimus muscles.

Other

  • Thigh (quadriceps compartment)
Compartments of the thigh
  • Buttock (gluteal compartment)
  • Arm (deltoid, biceps compartments)
  • Abdominal

Differential Diagnosis

Extremity trauma

Calf pain

Evaluation

Work-Up

  • xray to rule out fracture
  • Compartment pressure (see below; take serial measurements if needed)
  • Total CK, UA (rhabdomyolysis)
  • Chemistry (hyperkalemia)

Measure Compartment Pressure

  • Normal is <10 mm Hg
  • Pressures <20 mmHg can be tolerated w/o significant damage
  • Exact level of pressure elevation that causes cell death is unclear. It was previously thought pressure >30 mmHg was toxic although the "delta pressure" may be better predictor than absolute pressure

ΔPressure = [Diastolic Pressure] – [Compartment Pressure][3]

  • ΔPressure < 30 mm Hg is suggestive of compartment syndrome

Management

  1. Fasciotomy
  2. Support blood pressure in hypotensive patient
  3. Place affected limb at the level of the heart or slightly dependent
  4. AVOID ice (will further compromise microcirculation)
  5. Bivalve or remove cast if present
  6. Adequate analgesia
  7. Management for associated rhabdomyolysis if present

See Also

External Links

References

  1. Haddad, Steven L. Managing risk: Compartment syndromes of the foot. AAOS, 2007. http://www.aaos.org/news/bulletin/janfeb07/clinical1.asp
  2. Alexander W. et al. Acute lumbar paraspinal compartment syndrome: a systematic review. ANZ Journal of Surgery. 2018; 88: 854-859.
  3. Elliott, KGB. Diagnosing acute compartment syndrome. J Bone Joint Surg Br. 2003 Jul;85(5):625-32. PDF