Akinde has been troubled by the injury during his time on loan at Dagenham & Redbridge.
He was due to remain with the League One club until the end of the season but it looks increasingly likely that he will require an operation.
"It is really unfortunate for John. He's got a hernia problem and it seems he will need surgery," City boss Keith Millen told the club's official website.
"He has had one scan and is now set to speak to a specialist.
"It is disappointing for everyone concerned - John, ourselves and Dagenham. He needs to be playing games but his season could be over."