Kjetil Jansrud was examined in Oslo today and it is now clear that the internal ligament must be operated on.
There is still uncertainty around the cruciate ligament.
- Kjetil is gone for six to nine months, and we know more about what the injury actually means after the operation has been done, says national team doctor Marc Strauss.
The operation will take place at the end of next week.
36-year-old Jansrud has five Olympic medals and three World Cup medals on his merit list.
But there will not be a chance for new Olympic medals in Beijing this spring.