The A45 was closed to traffic in both directions for two hours following a collision early this morning.
A car and an articulated trailer were involved in the incident which had caused the closure from the A5 High Street in Weedon up to the B4037 towards Daventry.
The driver of the car was taken to hospital but his injuries are not thought to be life-threatening.
The A45 was reopened at 9.40am, two hours after police were called at 7.40am.
Fire services attended the scene to assist police and help the car driver be removed from his vehicle.