A slip road on to the A406 is partly blocked after a crash near the Redbridge Roundabout.
Emergency services were called to the collision on the carriageway towards Edmonton at 4.30pm.
A London Ambulance Service spokesman said a man in his 40s was treated for a shoulder injury and taken to North Middlesex Hospital, in Edmonton.
Firefighters from Woodford station cleaned a fuel spillage from the road.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here