The injury was sustained to his reconstructed shoulder while undertaking a training drill.
"Given Arryn has completed most of the training camp, the club has undertaken a cautious approach by allowing him to return home and recuperate in Melbourne," St Kilda Chief Operating Officer Ameet Bains told SAINTS.com.au.
"He will be further assessed over the coming days."
Drafted in 2010, Siposs played three games this year and has notched up 28 for his career.
