The Norway international was forced to leave his country's squad early after being injured just 16 minutes into Norway's 2-1 defeat by Wales last week.
Reports in Germany suggest the 28-year-old could miss Dortmund's clash with Werder at Signal Iduna Park. However, the injury is not expected to keep Ryerson out for an extended period.
Ryerson has become an important option for Dortmund on the right, and his absence would leave the club needing to adjust their defensive setup.
Maximilian Beier is one possible replacement and could be asked to operate as a right wing-back if Ryerson is not cleared to play.
Thomas Tuchel believes Alex Scott has given Declan Rice genuine competition for an England midfield place after an impressive first international start in the 7-0 win over Croatia.
Portugal head coach Jorge Jesus has left the door open for Cristiano Ronaldo to return to the national team after admitting the veteran striker was originally expected to play in the 2-1 Nations League win over Norway.
Manchester City are facing an anxious wait over Erling Haaland's fitness after the striker asked to be substituted during Norway's 2-1 UEFA Nations League defeat by Portugal on Sunday.
Jurgen Klopp has warned that Germany's next squad will be significantly smaller after praising his players for a "top-notch" performance in their 0-0 draw with Greece.
