Exertional Rhabdomyolysis in 8 Division I Female Lacrosse Athletes: A Case Series

XERTIONAL RHABDOMYOLYSIS (ER) is a complication of exercise that can be fatal if not recognized and treated appropriately. It is defined as the dissolution of skeletal muscle that produces a nonspecific clinical syndrome that causes leakage of toxic intracellular contents into the circulatory system. 1 This dissolution is manifested by increased extracellular myoglobin, potassium, phosphate, creatine kinase (CK), or urate that is released by the damaged myocytes. Release of these products into the bloodstream can result in decreased cellular function, renal failure, and even death in severe cases. 2 Most cases of ER are a result of muscle overexertion, alcohol abuse, muscle compression, or the use of certain medications. Initially, ER presents with symptoms similar to those observed with cases of delayed-onset muscle soreness (DOMS). Both DOMS and ER can occur after moderately strenuous physical exertion. Because of the similar manifestations of DOMS and ER, it is essential to obtain a proper history of an athlete’s activity levels, hydration levels, and medical history to ensure a proper course of treatment. 2 The pathophysiology of ER is a direct result of the energy requirements exceeding the athlete’s ability to produce adenosine triphosphate (ATP). As these requirements exceed production, the ATP-dependent sodium-potassium pump begins to fail, which results in an electrochemical disruption across the cell membrane and increased intracellular calcium levels. This increase initiates normally dormant enzymes that destroy the cell membrane, resulting in leakage of intracellular contents into the local circulation. ER is typically characterized by the release of intracellular contents into the local circulatory system that are signaled by an elevation in CK levels. 1,3 There are no toxic properties in CK, but elevated CK levels serve as a marker for increased permeability of muscle membranes. Although slightly elevated levels of CK might be observed in cases of DOMS, ER alone results in gross elevations of serum CK. 1 Serious complications of ER include renal failure, cardiac dysrhythmias, compartment syndrome, disseminated intravascular coagulation, lactic acidosis, and possibly death. 4 These can all be avoided with early recognition and treatment.