Atypical or sycamore myopathy is an uncommon, sudden onset, severe muscle disease, which is rapidly fatal in about 75% of cases.
This disease is seen most commonly in the autumn, in horses and ponies kept at pasture and is associated with the ingestion of sycamore seedlings.
It should not be confused with exertional rhabdomyolysis (ERM) commonly known as tying up which is a relatively common muscle condition occurring during or shortly after exercise.
