CECS is a form of exercise-induced ischaemia within a fascial compartment, caused when the fascia cannot stretch to accommodate the increase in volume caused by muscle contraction and swelling during exercise.
Presentation: Pain that occurs after a set duration of exercise, initially as dull aching and tightness, gradually increasing to the point where the affected person has to stop exercising, and resolving within a few minutes of cessation of exercise. The person is pain-free at rest. If intracompartmental nerves are affected then this can cause associated peripheral neurological symptoms. The compartment may feel palpably tense during symptoms (like a drum).
The lower legs are most commonly affected, but it can also affect the thigh, the forearm (gymnasts, climbers), and the foot (runners, aerobic training).
Runners and endurance athletes are the most commonly affected. Median age of onset is approx 20 yrs. Diabetes is a risk factor and may cause it to come on with minimal exertional activity. Both genders are at equal risk.
Complications: In rare cases, it can progress to acute compartment syndrome (when athletes continue competing despite pain).
Differential diagnosis: Bear it in mind as a differential diagnosis of claudication in diabetic patients, due to the possibility of minimal exertion triggering the symptoms. Other differential diagnoses of lower leg CECS include muscle strain, medial tibial stress syndrome, stress fracture, and popliteal artery entrapment. Note that medial tibial stress syndrome and tibial stress fractures both cause localised pain over the bone (not the soft tissue) and pain at rest and on first impact, with no delay in onset as is typical with CECS. However, bear in mind that the conditions can coexist.
Diagnosis: Pre- and post-exertion intracompartmental pressure testing.
Management: Start with conservative treatment – reducing or stopping the trigger activities, NSAIDs, bracing, stretching, orthotics as indicated for alignment anomalies that may be triggering the problem, gradual return to activity once symptoms resolve. (There is, however, no real evidence for this approach, and despite recommending it the authors stated that it was ineffective in most cases.) Surgical intervention involves subcutaneous fasciotomy via small incisions, which gives good results overall. Fasciectomy/excision of a band of fascia can be used in resistant cases.