The 24-year-old forward sustained the injury in March, but played through the discomfort to feature for his club Arsenal towards the end of the season to help them secure their first Premier League title in more than two decades.
Saka also appeared in the Champions League final against Paris Saint-Germain, which Arsenal lost on penalties.
"Bukayo is still getting there, playing through discomfort at the end of the season, but obviously managing it and playing at a high level, but still not at 100%. He is the one we are building and taking care of in training," Tuchel told reporters on Tuesday.
"Some things are missing... consecutive trainings. They (Arsenal) took very good care of him and were very aware of it... and we will do a little bit the same.
"They brought him back against Fulham when the season and title was on the line, and he was straight away decisive.
"And then they decided together, Bukayo and Arsenal, to let him play through his pain and discomfort, even if it was not possible to train the whole week in the build-ups."
Saka's fitness could be key for England's World Cup ambitions. He played in the 2020 and 2024 European championships and scored three goals in four appearances at the 2022 World Cup in Qatar.
England kick off their campaign on June 17 in Dallas with a repeat of their 2018 World Cup semi-final against Croatia.
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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