Editing Compartment syndrome (section)

== Aetiology ==

* External compression
** Cast/ACE wrap
** Military antishock garments
** Burn eschar
* Internal compartment expansion (most common)
** '''Ischaemia and reperfusion (the classic example - swelling occurs once tissue is reperfused)'''
*** Muscle injury leads to increased microvascular permeability with efflux of plasma proteins and progressive interstitial oedema. Oxygen radical generation exacerbates both these factors.
*** Risk factors:
**** Ischaemia time >6 hours
**** Young age
**** Insufficient arterial collaterals
**** Acute time course of occlusion
**** Hypotension
**** Poor back-bleeding from distal arterial tree at embolectomy
** '''Arterial injury, thrombosis, tourniquet'''
*** Injuries to popliteal artery are notorious for compartment syndrome (61%) compared with injuries above the knee
** '''Burns, frostbite (when there is a circumferential eschar)'''
** '''Cellular insult and swelling'''
*** Crush injury
**** Combination of direct muscle injury and ischaemia-reperfusion
*** Exercise/exertion/anterior leg compartment
*** Electrical injury/high voltage
** '''Blood accumulation and oedema'''
*** Fractures
**** Mostly tibial/forearm fractures
*** Haemophilia
*** Anticoagulants
*** Venous occlusion (can occur with iliofemoral thrombosis/external pressure)
**** Only occurs with extensive multilevel DVT with occlusion of venous collaterals
** '''Miscellaneous'''
*** IV infiltration/extravasation
*** Drug injection/soft tissue