Shelby Township police say a trailer that came unhitched caused an accident with serious injuries on M-53 near 25 Mile Rd. on Tuesday morning.
Northbound M-53 is back open at 23 Mile after being closed for several hours while police investigated.
Police say the trailer became unhitched from another vehicle traveling northbound, and a man driving a Pontiac G6 collided with the trailer.
The Madison Heights man was taken to Beaumont Hospital in Troy with serious injuries.
Right now, police are asking any witnesses to call them at 586-731-2121 and haven't said when the highway is expected to reopen.