World Rugby said that as of Wednesday, with the pool stage finished, 23 medical replacements had been drafted into the current World Cup tournament since the official team arrival dates, plus four more from the initial team announcements.
This compares with 21 in 2011, 38 in 2007, and 22 in 2003 - figures for the entire tournaments.
Some commentators have called the present World Cup the worst ever for injuries.
But World Rugby said in a statement: "All the indicators are that injury rates at Rugby World Cup 2015 are not out of step with those at Rugby World Cup 2011."
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It said "major advances" in player care and "the most progressive programme of welfare standards" ever to operate at a rugby event were helping raise standards of care on and off the field.
As rugby players are increasingly bigger and faster, the potential dangers of the sport have become a prime concern for authorities.
World Rugby said player care policies at this tournament included mandatory cardiac screening, independent medics for head injuries, use of video technology to help identify and assess head injuries, and independent concussion experts to consult on return to play.
Pitch-side medics must also have completed mandatory qualifications.
(Reporting by Angus MacSwan; Editing by Neville Dalton)
