A vehicle seat adjustment mechanism may include a gearbox, a first gear, a second gear, and a spindle screw. The first gear is received in the gearbox and is rotatable relative to the gearbox about a first axis. The second gear is received in the gearbox and is rotatable relative to the gearbox about a second axis that is perpendicular to the first axis. The first and second gears are meshingly engaged with each other. The spindle screw is meshingly engaged with the second gear and extends through the second gear along the second axis. The spindle screw may have trapezoidal threads.