Elsom, one of the world's best blindside flankers when fit, has managed just three games in an injury-blighted 2012 campaign.
"Rocky is still recovering from a shoulder injury and it's getting better all the time, but we probably won't see him this year unfortunately," Foley told reporters. "He's signed to play in Japan and we wish him well."
Elsom, 29, played over 60 matches for the Sydney-based Waratahs in his first stint from 2003-2008 before heading to Ireland where he helped Leinster win the Heineken Cup in 2009.
He returned to Australia soon after and led the Wallabies for the best part of two seasons before being replaced as captain by James Horwill just weeks out from last year's World Cup in New Zealand.
Elsom was omitted from Australia's squad for the recent tests against Scotland and Wales, effectively ending his 75-Test career.