A backrest for a motor vehicle seat, in particular for a rear seat

A backrest for a motor vehicle seat, in particular for a rear seat, includes a one-piece structure (1a, 1b) of light alloy, the lower portion having hinge means (17) for pivoting the backrest (1a, 1b) about a pivoting axis (A) transverse the body (B) of the motor vehicle. The lower portion of the backrest (1a, 1b) includes a base cross member (5) lying mostly above the pivot axis (A) and parallel thereto, a pair of integral end wings (11) extending downwards from the base cross member (5), with the hinge means (17) attached to them. The end wings (11) extend substantially in the same plane as the base cross member (5) and are connected to each other by a lower cross member (15) which extends downwards from the base member (5).