Tuesday, November 4, 2008
Every week an epidemic of injured joints affects pro football players. A shoulder separation here, an ankle sprain there, toss in a few knees and it’s an orthopedic surgeon’s dream or nightmare. Football is a game where high mass objects clouding at high velocity generate high force. Regardless of age or physical condition, the body’s joints still obey the rules of physics and as players get larger and faster, the joints will be the first to go. This week it was quarterback hell: Roethlisberger , Orton and Schaub.
There is not just one type of joint in the body. The hip and shoulder are ball and socket joints allowing range of motion in multiple directions. The knee is a hinge joint (with a tiny bit of slide built in) that just flexes and extends. Some joints like the acromio-clavicular joint, the one that is damaged in a separated shoulder don’t move much at all.
They all share some of the same building blocks. Two bones come together and the space in between has cartilage a cartilage surface to allow the joint to move without rubbing bone on bone. There are ligaments that attach to the bones on each side to allow stability and prevent motion in unattended direction. And there are muscles and tendons that stretch across the joint to move it.
Most of the time in the normal world, ligaments are enough to keep joints moving in the right direction. For football players, the ligaments need some help to stabilize joints and that’s where muscles enter the picture. Aside from providing power to move the joint, strong muscles are key to absorbing the outside forces placed on that joint.
Sometimes those forces come from another player and sometimes they are generated within the player. The knee is a good example. If a foot is planted when a hit occurs, the hamstrings and quads need to tighten to help the knee ligaments keep the joint from exploding. Even with muscles that have been in the weight room forever, if the outside force is too high, the ligaments fail and tear. The ligaments can also tear if the player tries to twist at the same time as planting the foot. The muscles aren’t aligned in the same plane as the body and the torque may be enough to cause the knee to give way. The same principles exist for throwing injuries in the arm. If the mechanics aren’t right, too much stress may be placed on the elbow and shoulder and ligaments can fail.
As players get bigger and faster, the forces that are generated increase to the point that the human body may be less able to survive them without injury. It is the rare pro player, who isn’t huge, but size doesn’t stop in the pros. High school and middle school athletes are getting larger too and often there isn’t enough muscle strength to help protect still growing bones and joints.
The NFL player has made it to the top of his profession because of his skills and athletic ability and because he has won the war of attrition. But once the game starts, he faces other players who have won similar wars and who equally want to win the next one. The difference between winning and losing may be just a few extra minutes in the weight room.