The 26-year-old was expected to be part of the Super Eagles squad out in Brazil before suffering a muscle tear during a pre-tournament friendly with Greece.
However, the left-back has now returned to training with club side Monaco.
Echiejile tweeted: "First training session with my team #ASMONACO. Amazing feeling, good to be back with the boys. #Happy."
Nigeria reached the last 16 of the World Cup before losing 2-0 to France.