The anterior compartment syndrome in the lower leg. Review and role of the EMG examination.

The Anterior Compartment Syndrome is a relatively rare affection with a wide spectrum of etiologies. Like every compartment syndrome, it is a condition in which high pressure in a rigid osteofascial space reduces capillary blood perfusion so that tissue viability is threatened. When pressure remains sufficiently high for a number of hours, normal muscle and nerve functions become disturbed which may lead to myoneural necrosis. Therefore, an early decompression by means of fasciotomy is essential. Clinical examination is of critical importance in reaching a diagnosis: first of all a painful swelling occurs, followed by muscular paresis or paralysis, and finally loss of sensation and a "silent" electromyogram (EMG). In some cases pressure measurements are necessary, in which tissue pressures over 30 to 40 mm Hg are considered abnormal. The EMG-examination is useful in order to achieve a diagnosis and to assess the degree of injury. It may be an important guide for further rehabilitation.