Compartment syndrome

Overview

Compartment syndrome is a serious medical condition that occurs when excessive pressure builds up within a closed muscle compartment. This pressure impairs blood flow and tissue perfusion, potentially leading to muscle and nerve damage, and, if untreated, tissue death. The syndrome is most common in the limbs and can be either acute or chronic. Acute compartment syndrome is a surgical emergency, while chronic (exertional) compartment syndrome is typically exercise-induced and managed non-emergently.

Causes

The causes of compartment syndrome differ between the acute and chronic forms:

• Acute Compartment Syndrome:

  • Trauma: Fractures, especially of the tibia or forearm bones

  • Crush injuries: That cause massive swelling or bleeding within a compartment

  • Reperfusion injury: After restoring blood flow to an ischemic limb

  • Tight casts or bandages: That restrict expansion of the underlying tissue

  • Burns: That cause edema under non-compliant skin or eschar

• Chronic Compartment Syndrome:

  • Repetitive exercise: Especially in runners, athletes, or military personnel

  • Muscle hypertrophy: Leading to increased pressure during activity

Symptoms

The symptoms of compartment syndrome vary depending on the type:

Acute Compartment Syndrome

• Severe, unrelenting pain: Out of proportion to the injury and worsened by passive stretching of the muscles

• Swelling and tightness: In the affected limb

• Paresthesia: Tingling or burning sensation due to nerve compression

• Pallor and pulselessness: In severe, late stages (though pulses may still be present)

• Paralysis: A late and ominous sign of irreversible damage

Chronic (Exertional) Compartment Syndrome

• Recurrent pain: That starts with exercise and subsides with rest

• Tightness or cramping: In the leg, forearm, or other muscle groups

• Numbness or weakness: During or after activity

• No pain at rest: Unlike the acute form

Diagnosis

Early diagnosis is crucial, especially in acute cases. Diagnostic approaches include:

• Clinical evaluation: Based on signs and symptoms; "6 Ps" are often referenced: pain, pallor, paresthesia, paralysis, pulselessness, and poikilothermia (coldness)

• Compartment pressure measurement: A needle manometer or catheter is used to measure intracompartmental pressure; pressures >30 mmHg or within 30 mmHg of diastolic blood pressure suggest acute compartment syndrome

• Imaging: Rarely used for diagnosis, but MRI or ultrasound may help evaluate chronic cases or rule out other causes

• Exercise testing: For chronic cases, measuring pressure before and after exercise may confirm the diagnosis

Treatment

Treatment depends on whether the condition is acute or chronic:

Acute Compartment Syndrome

• Immediate fasciotomy: Surgical decompression of the affected compartment is required to restore blood flow and prevent permanent damage

• Supportive care: IV fluids, pain management, and monitoring for kidney damage due to muscle breakdown (rhabdomyolysis)

• Removal of constrictive dressings or casts: Should be done immediately if contributing to pressure buildup

Chronic Compartment Syndrome

• Activity modification: Avoiding exercises that trigger symptoms

• Physical therapy: To improve flexibility and biomechanics

• Orthotics or gait training: In cases related to poor running mechanics

• Elective fasciotomy: May be considered for persistent, function-limiting symptoms

Prognosis

The prognosis of compartment syndrome varies greatly based on promptness of treatment:

• Acute compartment syndrome: Delayed treatment (over 6–8 hours) can lead to irreversible muscle and nerve damage, limb dysfunction, or even amputation. Early fasciotomy typically results in good recovery.

• Chronic compartment syndrome: Generally has an excellent prognosis with non-surgical or surgical management. Permanent damage is rare in these cases.

Long-term follow-up is often needed to assess functional outcomes and rehabilitation needs.