The Vikings have revealed half-back Danny Craven suffered a fractured right collarbone during his side's 28-14 win, while the Broncos confirmed Australian centre David Howell broke his arm.
The 21-year-old Craven will have surgery this week and will be out for 12 weeks. Howell, 29, who had corrective surgery on an injured thumb during the close season, broke his arm in the second half of the match at the Twickenham Stoop and was taken to hospital.
A Broncos spokesman said: "No set time has been set for Howell's recovery period at this stage. Everyone at the club wishes David a speedy recovery."
London captain Craig Gower, who left the field early in the first half, will be working with the club physiotherapists this week in a bid to lead his side at Huddersfield on Sunday.
The spokesman said the injury "doesn't look too serious".