creation date: 2026-04-21 19:09
tags: Pathologies
Acute Compartment Syndrome
Background
Definitions
Compartment syndrome refers to increased pressure within a compartment that compromises circulation and tissue function.
Compartments are sections of muscle groups within the limbs divided by strong, unyielding fascial membranes.
Compartment syndrome can occur acutely but chronic syndromes may be seen in athletes and typically have a more insidious onset. Acutely, compartment syndrome is a surgical emergency.
Etiology and Risk Factors
Acute compartment syndrome often occurs after significant trauma, typically when long bone fractures are involved. However, any condition that decreases volume capacity of a compartment or increases volume of fluids within a compartment can increase risk.
Causes include:
- Fractures (75% of cases)
- Nonfracture trauma (eg. crush injury, severe burns, circumferential constriction such as bandages)
- Nontraumatic causes (eg. bleeding disorder, anticoagulation, massive fluid resuscitation, prolonged limb compression)
Compartment syndrome can occur in any distinct anatomical compartment. Common sites (in order of incidence) include:
- Leg (knee to ankle) - comprises of anterior, lateral, deep posterior, and superficial posterior compartments
- Forearm - deep and superficial volar compartments, dorsal compartment, mobile wad (lateral)
- Arm - anterior (flexors) and posterior (extensors) compartments
- Thigh - anterior, posterior, medial
Less common sites include the foot, hand, and gluteal regions.
Pathophysiology
Regardless of cause, compartment syndrome occurs due to either intracompartmental space decrease or intracompartmental fluid volume increase. The compartment pressure increases because the surrounding fascia is non-compliant.
As compartment pressure increases, venous outflow is restricted, increasing venous pressure. If intracompartmental pressure becomes greater than arterial pressure, inflow will be impaired as well. The end-result is decreased perfusion of tissues causing ischemia and eventually irreversible necrosis.
A compartment pressure within 10-30 mmHg of DBP is at risk of compromising perfusion. As pressure approaches MAP, muscle oxygenation decreases.
Clinical Presentation
Signs & Symptoms
The symptom that raises suspicion for compartment syndrome is a tense, painful muscle compartment. Otherwise, signs and symptoms generally progress in a stepwise fashion.
Symptoms include:
- Pain out of proportion to apparently injury (early finding)
- Persistent deep ache or burning pain
- Paresthesias (30-120 min from compartment syndrome, ischemic nerve dysfunction)
Signs include:
- Pain with passive stretching of muscles of affected compartment (early finding)
- Tense compartment, wood-like feeling
- Pallor from vascular insufficiency
- Diminished sensation
- Muscle weakness (2-4 hrs)
- Paralysis (late finding)
Note that classics signs of arterial insufficiency (five Ps) are generally not accurate for compartment syndrome.
History & Physical Exam
History should include preceding events, especially history of trauma. Pain should be characterized.
Consider risk factors for DVT.
Physical exam should focus on neurovascular components of the compartment:
- Skin changes (swelling, lesions, colour)
- Palpation of temperature, tension, tenderness
- Pulse
- Evaluation of two-point discrimination and sensation
- Evaluate motor function
Diagnosis
Criteria
Diagnosis is made clinically with rapid progression of signs and symptoms concordant with the condition.
A measurement of compartment pressures can be made to support the diagnosis but is not required.
Work-up
Laboratory studies
Laboratory studies are not used for diagnosis and should not delay surgical consultation.
Lab changes seen may include:
- CK (elevated - due to rhabdomyolysis)
- Myoglobinuria
Measurement of compartment pressures
A surgeon may measure compartment pressures.
- Handheld manometer (eg. Stryker)
- Simple needle manometer system
- Wick/slit catheter technique
Compartment pressure normally falls between 0-8 mmHg. Compartment syndrome measurements may be around 30 mmHg.
Differential
Other diagnoses include:
- Deep vein thrombosis
- Cellulitis
- Gas gangrene
- Phlegmasia cerulean dolens
- Rhabdomyolysis
- Cnidaria envenomation
- Peripheral vascular injuries
Red Flags / Complications
The major complication of untreated or late-treated compartment syndrome is loss of limb function. If untreated for ≥6 hours, there may be residual nerve damage. Beyond 12 hours, many patients have permanent limb function impairment.
In the most extreme cases, the limb may require amputation.
Management
Treatment consist of immediate surgical consult.
Supportive care while awaiting surgical consult/intervention include:
- Supplemental oxygen
- Remove restrictions (eg. casts, bandages)
- Keep extremity level to heart to prevent hypoperfusion
- Prevent hypotension
In cases of rapidly progressing compartment syndrome and surgical intervention is not available, a fasciotomy is required to prevent complications.