This past Sunday FIFA player of the year Cristiano Ronaldo was injured in the eighth minute of the finals of the European Championships.  He attempted to play through the injury but was unable and came off in the 25th minute.  For the world's best player to come off in a final, it meant that he sustained a serious knee injury, with pundits around the world speculating on the extent of his injury.

Watching the match live, it appeared to me to be an MCL injury as he was hit on the outside of his knee forcing the knee inward.  These types of valgus stress injuries usually result in an MCL sprain.  Other structures such as the ACL and/or meniscus can be injured but since he did not come out of the match immediately it is less likely that they were.  It's very difficult to play soccer with an MCL injury due to not only the cutting and pivoting required, but even more limiting is the inability to pass with the inside of the foot due to the stress on the ligament.

Now that the a few days have passed and Ronaldo has had more thorough evaluations, it has been determined that he indeed has an MCL sprain. This means Ronaldo suffered a stretch in the ligament, and fortunately not a complete tear that would require surgery.  These injuries are typically graded on a 1-3 scale with grade 1 being mild with no significant laxity and minimal injury to the ligament.  Grade 2 is moderate injury with some laxity and partial tearing of the ligament.  Grade 3 is a severe injury with gross laxity and complete ligament disruption often requiring surgical repair.  Other structures such as the ACL and either meniscus can be injured as well as the articular cartilage (joint surface cartilage).  These all add to the severity of the injury, time frame to return, and if surgery is indicated.

Return to play is variable with this injury, especially in soccer players.  With grade 1 injuries, it's based on the player's symptoms and ability to progress through rehab and training.  Caution needs to be taken with early return as re-injury is possible and if the knee is not 100 percent there is a greater risk of ACL injury to the involved or uninvolved knee.  In grade 2 injuries, progression through rehab is based more on the healing of the ligament which is assessed through the amount of laxity or looseness in the knee.  This laxity decreases as the ligament heals and the knee "tightens up" over time.  Grade 3 injuries require a much longer time frame to heal, if they don't require surgery.  Although the return to play time frames for MCL injuries in soccer can be widely variable, a general guideline is a grade 1 injury takes 2-6 weeks to rehab, 3-8 weeks for grade 2, and 2-4+ months for grade 3.  Internet speculation has him out as little as three to four weeks, a middle ground guess of eight weeks, and as much as four to five months as a worst case scenario.

As more details come out regarding Cristiano Ronaldo's injury, more specific time frames will be given.  As a soccer fan, I'm hoping he's ready for the start of the La Liga season and Champions League.  Love him or hate him, Real Madrid matches are more exciting with him on the pitch.

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