A Report on Knee Injuries

There are lots of soccer injury statistics in sports medicine magazines. As mentioned in a prior article, the ankle is the most injured body part, but the knee follows.

To see if there are any suggestions that could be made in the way of preventive measures that might reduce the number and severity of knee injuries, we need to know how the injury happened.

Most doctors will say that the majority of knee injuries happen when the foot is planted. 76% of the players said that their foot was planted at the time of injury.

Word of mouth comments frequently blame the condition of the field. The players we called (five out of every six) said the surface was flat and even.

Traction was excellent (4%), good (25%), average (44%), fair (24%) or poor (12%). When traction was fair or poor, it was due either to water or the field being very hard and dry.

Changing direction is a common mechanism of injury to the knee, especially in knee ligament sprains. Twenty-six percent (26%) of players with a knee injury were changing directions while 56% were not. The rest couldn’t recall.

If they were cutting, it was a routine cut (e.g. plant right foot, cut left).

We tried to get the player to estimate the knee flexion angle at the time of injury. Two-thirds of all knee injuries occurred at or near full extension. About one-third were about midway in the range of motion and only two injuries happened when the knee was flexed to an extreme degree.

At the time the knee collapsed, 54% of the time it collapsed to the middle, 30% to the outside and 15% were hyper-extended.

The player may or may not have heard a “pop” from their knee at the time of injury. Interestingly, 28% did not seek medical advice and thus did not receive a medical diagnosis. When a diagnosis was made it was: ligament sprain (60%), contusion (10%), cartilage damage (10%), and tendinitis (5%). The rest of the players who received a diagnosis couldn’t recall what it was.

Being thrown off balance and trying regain balance has been implicated in knee injuries. Eighty-eight percent of the players felt they had been knocked off-balance. Fifty-eight percent of those thrown off balance tried to regain their balance leading to the injury. Of those with a ligament sprain, it was about 50-50 whether they tried to regain their balance.

While only one in six players with a knee injury thought their shoe became “stuck” to the ground, all those who did think it stuck sustained a knee sprain. Of those who didn’t think their shoe was stuck, 43% of those injuries were knee sprains.

Remember, these results are preliminary, and should not be considered absolute.