The former Emmerdale actress first hurt her rib weeks ago but the injury has flared up again in recent days, The Sun claims.
Writing on Twitter, Tamaddon confirmed: "I'm shattered and have a crazy week ahead and I'm struggling with my rib injury. Must rest."
It is thought that the 33-year-old's next routine requires her skating partner Daniel Whiston to grip her on the sore area, adding to her training troubles.
A show source said: "All the muscles around her ribs have gone into spasm. Dan wrapping his arms around her for the trickier moves has aggravated it."
Dancing On Ice continues on Sunday at 7.20pm on ITV1.