Karena sakit punggungku kambuh, aku tidak bisa menghadiri pestanya Koizumi.

English Translation

Due to my lumbago, I won’t be able to attend Koizumi’s party.

Kambuh” means “recurring” or “relapsed”. But “lumbago” has acute and chronic ones. The English sentence misses the meaning of “kambuh”, which is much better for a cloze-word than {{Koizumi}} (a Japanese surname).