"Thank you @ford for equipping me with a car that kept my whole family @katyallen @ZorroPup and the little one we have on the way safe," Allen tweeted Tuesday.
Despite being in the "really bad wreck," Allen still plans to kick off his upcoming Out Alive concert tour in Killington, Vt., next week, MTV.com said.
Allen's mother, Kimberley, tweeted a photo of the singer on a gurney, along with the message: "From Kris: he's in a lot of pain, arm broke, may not play guitar for a while. ... Prayers welcome please! #headoncollision."
Kimberley also said her son and daughter-in-law were "pretty beat up" in the collision.
MTV.com did not say how and where the accident happened, or if any other parties were involved.
Celebrity Families of 2014 [PHOTOS]