The Russian had been in third place behind world champion Patrick Chan and Daisuke Takahashi after Thursday's short skate but crashed to the ice Friday and out of the competition.
Menshov, controversially overlooked by his country for the world championships in March, had put himself in contention for gold after a performance set to Rene Aubry's punchy Allegro.
A message on the Russian Figure Skating Federation website confirmed that Menshov, 30, had been admitted to hospital.
The star-studded event runs through Sunday at the Yoyogi National Gymnasium in Tokyo.
--IANS (Posted on 13-04-2013)