Three subway riders were killed walking in between cars last year, while other passengers were injured or delayed trains, transit documents show.

Police said Wladyslaw Kusiak, 53, did not survive falling between the cars of an uptown F train as it left the West 4th Street station about 7:50 p.m. Dec. 9. He later died at Bellevue Hospital.

Lorraine Ogarro, 54, of the Bronx died after tumbling between the cars of a No. 1 train at the 207th Street station on March 23. After falling, she was struck by another 1 train, and died on the tracks.

And TyAsia Matos, 20, of the Bronx was killed when she went in between No. 4 train cars to relieve herself at Grand Central Station on Sep. 6, shortly before her 21st birthday.

A new “open gangway” train design that the MTA will test out, which has no doors or the perilous footing between subway cars, may avoid such deaths in the future.

The design of the cars, which are similar to articulated buses, will allow the MTA to fit more passengers inside, and could encourage riders not to crowd around its doors.

But they could also prevent riders who walk illegally between cars from getting hurt or killed.

“Open gangway cars would eliminate the risk of people falling between subway cars because the passageway between cars would be enclosed,” said Max Diamond, a transit enthusiast who teaches workshops on subway cars.

“This could save many lives and reduce delays caused by customer injuries substantially.”

The MTA’s rules on conduct forbid riders from going in between cars, unless it’s an emergency or they are instructed to do so by a conductor or police officer.

“Passing through or riding between cars is dangerous and is strictly prohibited,” said spokesman Kevin Ortiz.

Other riders have survived mishaps between cars, but caused disruptions for commuters.

A man delayed seven trains on Oct. 3 when he tried to enter an F train by walking from the platform at the 57th Street station in between cars, and slipped onto the tracks. He survived and was treated at Cornell Hospital.

An unruly straphanger also made two trains late when he was climbing between cars at the Fulton Street station on May 28, transit documents say. He appeared to be intoxicated.