1. An involuntary and often painful contraction of the muscles in the back
She experienced a severe back spasm after lifting the heavy box.
Ela experimentou um espasmo nas costas severo depois de levantar a caixa pesada.
2. A sudden, uncontrolled muscular movement in the back region that may limit mobility
The back spasm left him unable to stand up straight for several hours.
O espasmo nas costas o deixou incapaz de ficar em pé reto por várias horas.