Orji has been sidelined by chickenpox.
Nigeria will set up a training camp in Pretoria, South Africa, for the final phase of their build-up for the championship for players featuring in their home leagues.
They are scheduled to play two warm-up games against Cote d’Ivoire and Angola, who have both qualified for the CHAN in Rwanda.
Nigeria are drawn with Tunisia, Niger and Guinea in Group C of the 2016 CHAN and play their opening match on January 18 in Kigali.