Brit Long, MD and Alex Koyfman, MD
Acute compartment syndrome is commonly due to fracture or acute trauma; however, it can be caused by several other conditions, including overexertion. Mavor in 1956 first described chronic compartment syndrome due to exertion in young athletes.5 This condition can be debilitating to patients, and it is commonly misdiagnosed.5-8
This condition most commonly affects young endurance athletes due to overexertion. Athletes affected include runners, gymnasts, soccer players, lacrosse players, and hockey players, with men and women equally affected.6-10 The prevalence is unknown, as many individuals suffering from the condition do not seek medical attention.7 Over 30% of patients with chronic lower leg pain may have elevated compartment pressures.8 Increased pressures occur in 28% of patients with recurrent, exercise-induced pain.9 The anterior compartment of the lower leg is most commonly affected.6,10-12 However, this condition affects many other populations and can include compartments in the foot, thigh, forearm (gymnasts and climbers), and hand.13-15
Compartment syndrome due to exertion is associated with several mechanisms, including inability to clear metabolic waste products due to decreased vascular flow.5-7 Exercise leads to increased vascular flow, causing muscular expansion and increased pressure.16-18 This pressure elevation reduces blood flow within the specific compartment, causing ischemia. Patients affected by this condition may have reduced capillary flow at baseline.19,20 Fascial defects are also common, as 20% to 60% of those with exertional compartment syndrome suffer from a fascial hernia near the intramuscular septum between the anterior and lateral compartments of the lower extremity.7-9,21,22
The patient with lower leg pain has an extensive differential, with many benign pathologies, though some may be life or limb-threatening. This differential is demonstrated in (Table 278-3).
Table 278-3Differential Diagnosis ||Download (.pdf) Table 278-3 Differential Diagnosis
|Differential for Lower Leg Pain |
|- Medial tibial stress syndrome (or shin splints) |
|- Venous vascular disease: deep venous thrombosis, phlegmasia alba dolens, phlegmasia cerulea dolens |
|- Arterial vascular disease: thrombus, embolus, popliteal artery entrapment, dissection |
|- Neurogenic claudication |
|- Lumbar radiculopathy and other conditions causing cord compression (malignancy, abscess, fracture) |
|- Peripheral nerve entrapment or injury |
|- Myopathy |
|- Periostitis |
|- Bone tumor |
|- Stress fracture of the tibia or fibula |
|- Tendinopathy |
Most patients with exertional compartment syndrome are athletes, who typically describe gradually worsening pain with exertion in a specific anatomical region. The pain can be characterized as aching, squeezing, cramping, or sharp, often with a specific time of onset during exercise.7,11,17,21,23 Symptoms are often bilateral and usually stop with rest. In the setting of severe ischemia, paresthesias and weakness can occur. Symptoms and examination findings are dependent on the specific compartment affected.24-26 Several findings increase likelihood of exertional compartment syndrome in the anterior compartment of the lower leg: pain induced by athletic activity only, pain limited to the anterior compartment of the lower leg, pain requiring the athlete to cease activity, and tenderness to palpation only in the involved compartment.9
Examination is commonly normal if the patient is resting.6,7,9 If the patient has recently exercised, the involved compartment may be tender to palpation. Weakness or absent pulses on examination suggest late stage disease, acute compartment syndrome, or another condition such as claudication or vascular disease.6,7,17,21,24 As opposed to exertional compartment syndrome, stress fractures and medial tibial stress syndrome have localized bony tenderness, with minimal soft tissue tenderness. They also have pain at rest and with first impact.
Acute compartment syndrome should be differentiated from the exertional form. Acute compartment syndrome presents with pain that does not resolve, pain out of proportion to examination, pain with passive stretching, paresthesias, and decreased or absent distal pulses in the involved extremity.6-8,23,24-26 Pain that resolves could be exertional; however, if pain does not abate after exercise, acute compartment syndrome should be assumed.14,27 Any objective neurologic finding, specifically weakness in the affected distribution, is concerning.
Laboratory studies do not provide definitive diagnosis. Serum creatinine kinase (CK) level will be elevated in the setting of rhabdomyolysis, and acidosis and myoglobinuria may be found.24,28
Consider consulting an orthopedic surgeon for further evaluation and management. Diagnosis relies on history and physical examination, though compartment pressures are a vital adjunct to the diagnosis of acute compartment syndrome. Failure to diagnose may result in permanent deformity and dysfunction.6-8
For patients with exertional compartment syndrome where the pain has resolved but the provider is considering the diagnosis, compartment pressure measurement is needed for definitive diagnosis.6-9,12,24 Measurement technique and timing recommendations differ among experts, though criteria includes timed measurements: preexercise pressure > 15 mm Hg, 1 minute postexercise pressure > 30 mm Hg, and 5 minute postexercise pressure > 20 mm Hg.6-9,29,30 These criteria are associated with a 5% false positive rate.10
Near infrared spectroscopy and magnetic resonance imaging (MRI) can be used for diagnosis, but these should not be obtained on an emergent basis. Both imaging tests display suboptimal capabilities, with inadequate sensitivity and specificty.31
Chronic exertional compartment syndrome management includes rest with exclusion of inciting activity. Non-steroidal medications, orthotics, stretching, and ice are adjuncts.10,11,14,28 If symptoms resolve, the athlete can gradually return to full activity over several weeks. However, conservative treatment is often ineffective.6-9 If compartment syndrome is confirmed by pressure measurement, surgical intervention including subcutaneous fasciotomy may be needed, with success rates of 80% to 90%. Patients with involvement of the deep posterior compartments or those with diabetes have decreased success rates and often require fasciectomy.25,32-34
Acute on chronic compartment syndrome requires emergent orthopedic surgery consultation with consideration of fasciotomy.