The 25-year-old last played for Tottenham on 25 October in an EFL Cup tie against Liverpool and will continue his rehab from at Spurs' training ground. The injury initial failed to respond to tratment and it is now expected that Lamela will not be fit until Spetember at the earliest.
Spurs flew out to the US on Wednesday ahead of friendlies against Manchester City, Roma and PSG.
The Argentine isn't the only player to be left behind, Mauricio Pochettino also elected to leave out Danny Rose, Son Heung-Min and Moussa Sissoko.
Rose is unlikely to be fit for the start of the new season after undergoing an operation to solve the knee problem that ravaged him during the second half of last season. Son meanwhile is continuing to recover from an arm injury picked up on international duty with South Korea and Sissoko, who Spurs are desperate to sell this summer, is suffering from a virus.
Tottenham's full squad can be seen below.
Here is our confirmed travelling squad for our trip to the USA… #SpursInUSA pic.twitter.com/ijyDaZKL7G
— Tottenham Hotspur (@SpursOfficial) 19 de julho de 2017