Trout told Sam Blum of The Athletic on Friday that his back has been a "non-issue" for four months.
Trout missed time last season with a rare back condition called costovertebral dysfunction, which is a chronic injury. However, he showed no ill effects after returning, posting a 1.056 OPS with 16 home runs over 40 games down the stretch. The back problem remains a long-term concern and Trout has been an injury risk in recent years even beyond the back issue. However, it has not affected his offseason work and he's on track to enter spring training healthy.