Knapik JJ, O’Connor FG. Exertional Rhabdomyolysis: Epidemiology, Diagnosis, Treatment, and Prevention. J Spec Oper Med. 2016 Fall; 16(3):65-71.
Exertional rhabdomyolysis (ER) is a medical condition whereby damage to skeletal muscle is induced by excessive physical activity in otherwise healthy individuals. The individual performs so much activity that he/ she presumably depletes local muscle energy stores and muscle cells are unable to maintain cellular integrity, resulting in cell damage and the release of cellular contents, with resultant secondary complications. In the military services, the incidence of ER appeared to increase in the period 2004 to 2015. Risk factors for ER include male sex, younger age, a prior heat injury, lower educational level, lower chronic physical activity, and activity in the warmer months of the year. Acute kidney injury is the most serious potential complication of ER and is thought to be due to a disproportionate amount of free myoglobin that causes renal vasoconstriction, nephrotoxic effects, and renal tubular obstructions. Patients typically present with a history of heavy and unaccustomed exercise with muscle pain, swelling, weakness, and decreased range of motion, largely localized to the muscle groups that were involved in the activity. Diagnostic criteria include the requisite clinical presentation with a serum creatine kinase level at least level 5 times higher than the upper limit of normal and/ or a urine dipstick positive for blood (due to the presence of myoglobin) but lacking red blood cells under microscopic urinalysis. Core treatment is largely supportive with aggressive fluid hydration. Although the great majority of individuals return to activity without consequence, patients should initially be stratified into high and low risk for recurrence, and those at high risk provided additional evaluation. Risk of ER in normal healthy individuals can be reduced by emphasizing graded, individual preconditioning before beginning a more strenuous exercise regimen after recommended work/rest and hydration schedules in hot weather, and discussing supplements and medications with knowledgeable medical personnel.
Children’s and Emory users, contact Emily Lawson for this article.
Armed Forces Health Surveillance Bureau. Update: Exertional rhabdomyolysis, active component, U.S. Armed Forces, 2012-2016. MSMR. 2017 Mar;24(3):14-18.
Among active component service members in 2016, there were 525 incident diagnoses of rhabdomyolysis likely due to physical exertion and/or heat stress (“exertional rhabdomyolysis”). The crude incidence rate in 2016 was 40.7 cases per 100,000 person-years. Annual rates of incident diagnoses of exertional rhabdomyolysis increased 46.2% between 2013 and 2016, with the greatest percentage change occurring between 2014 and 2015. In 2016, relative to their respective counterparts, the highest incidence rates of exertional rhabdomyolysis affected service members who were male; younger than 20 years of age; and black, non-Hispanic. During the surveillance period, annual incidence rates were highest among service members of the Marine Corps, intermediate among those in the Army, and lowest among those in the Air Force and Navy. Most cases of exertional rhabdomyolysis were diagnosed at installations that support basic combat/recruit training or major ground combat units of the Army or the Marine Corps. Medical care providers should consider exertional rhabdomyolysis in the differential diagnosis when service members (particularly recruits) present with muscular pain or swelling, limited range of motion, or the excretion of dark urine (possibly due to myoglobinuria) after strenuous physical activity, particularly in hot, humid weather.
Free full-text (click View the MSMR Archive and go to vol. 24, issue 3 to download article.)