Steven Petrov
The Paw Print
With more than 200,000 ACL tears each year within the U.S., this particular injury has become one of the most common and feared ones in the sports world. It is a season ending injury, which requires a surgical treatment under the form of a reconstructive surgery. The main causes for an ACL tear are a strong hit from the outside part of the knee, overextending, or the most common one: a quick stop and start with pivoting or changing directions which causes the knee to collapse inwards. This article is not meant for diagnosing injuries or for any medical recommendations, but instead it will focus primarily on the importance of the surface that athletes play on and will compare the injury rates for both the increasingly popular turf field and the “old-fashioned” natural grass field. The reason for this investigation and comparison is the observed higher knee injury rate on turf fields, and the feeling of their foot “getting stuck in the turf field” that athletes all around the country share after suffering a knee injury.
Ever since the turf fields have been around as an option and alternative to the regular grass fields for more than 40 years now, the innovative artificial grass has numerous obvious advantages which are directly related to the evenness of the field, which allows for a quicker speed of play and better quality of performance by the athletes. Another major determinant of using turf is the little to no “maintenance” that has to be done to it. Unlike the natural grass, which has to be watered, cleaned from soil imperfections, cut, and of course snow cleaned during the winter, some of the modern day artificial fields even have a warming system which encompasses the whole field and is used to melt the ice or snow during the winter, making it virtually an all-year usable facility. However, there are two main aspects that have always been in the focus of all researches of turf fields and their contribution to major knee injuries like ACL tears and they are: Coefficient of Friction and Coefficient of Restitution. What these two respectively represent are the force needed for a planted foot to slip or rotate, and the field’s ability to absorb shock when an athlete collides with the surface. The ability to make a quick turn after having planted their foot is the exact moment when athletes talk about the feeling of having their foot stuck into the “infill” of the nylon grass, which is usually either composed of rubber or silica pellets with sand. The high density of the rubber “infill” doesn’t allow the athlete’s foot to turn normally and the whole force of the turning process goes up through the joints from the ankle, up to the knee and hip joints. With the knee being the most complex joint, as well as the most vulnerable to injuries, it is clear why knee injuries are of predominant presence among athletes.
The ASU’s men soccer team has had 3 ACL tears in the past 6 months and each one of the injured athletes describes the moment of the injury as getting “stuck” in the rubber “infill” of the field, while trying to turn. The ability to absorb shock is also important due to the fact that, regardless of the efforts of scientists to make the artificial fields reach that “perfect” shock absorbing and soft feeling that the well preserved natural grass has, are still not providing the needed results, which definitely increases the risk of contusions and concussions after an impact with the turf’s surface.
The topic is a long and really controversial one, with proponents on each side of the argument. Should the number of artificial turf fields be increased or decreased and shouldn’t there be more well managed and preserved grass fields? Through personal experiences I have concluded that the long cleats that football, soccer, lacrosse, etc. athletes are used to wear on grass fields, increase the chance of experiencing the “getting stuck” in the turf phenomenon which leads to a series of bad injuries to the athlete’s body.
What’s Been Said…