Acute compartment syndrome is a limb and life-threatening surgical emergency. It is a painful condition caused by increased intracompartmental pressure, compromising perfusion and resulting in muscle and nerve damage within that compartment.
Acute compartment syndrome is more common in men under 35 years of age . It is ten times more common in males and most commonly seen following tibial shaft fractures .
There are five characteristic signs and symptoms for acute compartment syndrome and they generally appear in a stepwise fashion:
- patients with acute compartment syndrome often report pain in which the severity is out of proportion to the apparent injury
- this is an early and common finding
- often described as deep and burning in nature
- paresthesia: this suggests ischemic nerve injury
- pallor: this occurs secondary to vascular insufficiency and is uncommon
- pulselessness: uncommon
- paralysis: this is rare and often a late finding
Causes for compartment syndrome include:
- limb trauma
- overuse (endurance athletes)
- muscle hypertrophy
- animal bites
- bleeding in a joint or enclosed compartment
- intramuscular injections
Acute compartment syndrome results primarily from an increase in intracompartmental pressure. This is often associated with trauma such as fractures or muscle injury. It occurs when the interstitial pressure within the compartment exceeds the perfusion pressure of the capillary beds, causing irreversible myonecrosis due to cellular anoxia . If the intracompartmental pressure is below the perfusion pressure, ischemia occurs which is reversible.
Acute compartment syndrome is diagnosed based on clinical findings and the measurement of compartmental pressures. The utilization of imaging is generally limited . In many cases, imaging may delay the diagnosis and time to surgical treatment.
MRI and US may show muscle edema and swelling. The normal fascicular architecture is often lost. In myonecrosis, muscle enhancement on T1 post gadolinium sequences is absent and decreased in ischemia.
Sequelae of chronic compartment syndrome include muscle atrophy, scarring, and dystrophic calcification.
Treatment and prognosis
Immediate management of suspected acute compartment syndrome involves relieving pressures on the compartment (e.g. dressing, splint, or cast) and placing the limb at the level of the heart.
If conservative management is unsuccessful, emergent fasciotomy is usually required for limb salvage.