We report a 30-year-old man who developed painful swelling of his righ
t leg and complete sciatic nerve palsy after an IV injection of heroin
. Excessive elevation of serum creatine phosphokinase indicated the pr
esence of rhabdomyolysis. Fasciotomy of the gluteus maximus led to rap
id and complete recovery from sciatic nerve palsy. Nontraumatic rhabdo
myolysis may cause a gluteal compartment syndrome that requires immedi
ate fasciotomy.