A 32-ton lorry was in collision with another truck on the M6 near Walsall, causing long delays for motorists.
The accident happened on the southbound carriageway just before 0800 BST at junction 10 of the motorway.
The road was closed while firefighters cut one of the drivers free from the wreckage of his vehicle.
A West Midlands Fire Service spokesman said that his condition is not life-threatening.
All three lanes of the motorway have now been reopened at junction 10.
But a Central Motorway Police spokesman advised drivers to avoid the area altogether if possible.