Description

An irreversible flexion contracture at the wrist following ischemic injury (most commonly from compartment syndrome):

• Compartment syndrome occurs when the pressure within the closed compartment of a limb is elevated resulting in decreased perfusion; can occur from either internal swelling (as in a crush injury) or external constriction (tight cast or splint)
• Volkmann contracture is a late sequela of the ischemic injury and is not part of an acute compartment syndrome.

Epidemiology

Incidence

• Rare due to early detection of compartment syndrome and prophylactic fasciotomy
• 0.5% incidence in upper extremity pediatric long bone fractures

Etiology and Pathophysiology

• Compression of the brachial artery leads to ischemic injury of the forearm flexors (primarily the flexor pollicis longus and the flexor digitorum profundus). If unrecognized, compartment syndrome develops leading to irreversible myonecrosis, secondary fibrosis, scarring, and muscle contracture with resultant “claw-like” deformity of the wrist.
• The neuromusculature of the forearm can tolerate ischemia for up to 4 hours; irreversible damage occurs after 8 hours.
• Can be accompanied by median (more common) and/or ulnar nerve injury, with a resultant sensory neuropathy

Genetics
No known genetic predisposition

Risk Factors

Compartment syndrome associated with:

• Trauma
• Fracture, particularly supracondylar fractures of the humerus in children, distal radial fractures in adults
• Arterial embolus
• Burns
• Muscle hypertrophy
• Overly tight bandages/dressings
• Tourniquet application
• (Rare) snake (most often vipers) or insect sting (usually bee or wasp)

General Prevention

High clinical suspicion of compartment syndrome is required for early diagnosis and treatment (fasciotomy).

Commonly Associated Conditions

• Displaced supracondylar humerus fracture and forearm fractures in children
• A congenital variety occurs in newborns associated with skin lesions on the affected arm.
• Distal radial fractures in adults
• Myoglobinuria, metabolic acidosis