The Tottenham centre-half was forced off after just 14 minutes of the home win over Scunthorpe on Saturday following a collision with a post which has left the 19-year-old with a badly-bruised hip bone.
"He is still very sore and having trouble walking, so must be a doubt for the next game," said City manager Keith Millen.
"But he had a similar problem earlier in the season and recovered quickly.
"We should know in the next day or so whether he will recover in time to play at Coventry. We have cover and Damion Stewart came in and did a good job, but it is too early to write Steven off."
Source: PA
Source: PA