Compartment Syndrome of the Lower Leg (Exercise Induced)

Summary

Compartment syndrome of the lower leg is a condition characterized by intense pain and swelling in the leg over the involved muscles. These muscles are confined in relatively unyielding compartments formed by the thick fibrous tissue (fascia) and bony walls that surround them, and when they swell they can sometimes reach a point where blood will not reach (perfuse) the muscles. This results in intense pain and eventual muscle death. Compartment syndrome often occurs in the setting of a trauma, such as a lower leg (tibia) fracture. However, it can also occur following exercise in patients that are at risk.

History

Exercise-induced compartment syndrome classically presents with marked pain in the lower leg, usually in the front or side of the lower leg following an episode of intense or prolonged exercise or activity. There may be associated numbness in the foot, and the muscles lifting the foot up may become dysfunctional, leading to difficulty in lifting the foot up, a condition called ‘foot drop’ or ‘drop foot’. A common scenario is a patient who is playing an intense game such as tennis and develops pain, numbness, and a drop foot. If they stop playing, the symptoms will usually resolve, although there can be a low level dysfunction of the involved muscles. In a worst-case scenario, the muscles do not become adequately oxygenated (perfused) after the exercises stop, and there is some muscle death.

Physical Exam

Patients with an exercise-induced compartment syndrome of the lower leg will often have a fairly normal physical exam when they are not exercising. However, the symptoms can be reproduced if they exercise. This would include a hard swelling of the muscles usually in the front or side of the lower leg, as well as weakness, and difficulty or inability to lift the foot up. There may also be numbness on the top of the foot as the nerves supplying this area run through the compartments in the front and side of the leg.

In an effort to reproduce the symptoms, patients may be asked to exercise and then the compartment pressures could be measured. If they are noted to be within 20 or 30 mm of the lower blood pressure measurement (the diastolic pressure), then the diagnosis of compartment syndrome would be made.

Treatment

Treatment of exercise-induced compartment syndrome initially may involve avoiding aggravating activities. There are often just a few very specific activities that will precipitate symptoms, and if the patient can avoid these then they can usually function without any other intervention.

Surgical Treatment

For persistent exercise-induced compartment syndrome or compartment syndrome that is recurrent and debilitating, release of the involved strong tissue (the fascia) that confines the muscles is indicated. Essentially this involves cutting through skin and the soft tissues down to the tense tight fascia overlying the involved muscles. This fascia is cut, creating a space for the muscle to expand into and therefore allowing for adequate perfusion when the muscles are being used.

Occasionally an acute exercise event, such as a long tennis match or a running race, may produce compartment syndrome that does not resolve. This is a surgical emergency and would require a release on an urgent basis of the involved tense compartments. If release does not occur within an adequate time, there is often death of the muscles with associated dysfunction such as a drop foot.

Previously Edited by Vinod Panchbhavi MD

Edited April 19, 2018

mf/ 7.16.18