A victim of Tuesday’s A train derailment has already filed a $5 million legal claim against the MTA over neck and back injuries.

Sheena Tucker, 31, of Harlem was on a Brooklyn-bound train near the 125th Street station at 9:45 a.m. when the car slammed up against a subway tunnel wall, according to her notice of claim.

She is planning to speak about her injuries at a press conference Thursday afternoon. Her claim, a precursor to a lawsuit, says that she’s suffering from “serious and severe personal injuries..including but not limited to injuries to the neck, back, right side and other physical injuries, psychological injuries, [and] emotional trauma.”

Tucker is blaming the MTA for “reckless, careless and negligent” maintenance of the subway system.

She is one of 39 people who were hurt during the morning commute. She is the first victim to file legal papers over the incident.

The MTA has blamed the accident on an unsecured piece of rail on the tracks.

An agency rep did not immediately return messages for comment.