If you like golf, you probably remember watching Tiger Woods win the 2008 U.S. Open with a torn anterior cruciate ligament (ACL). This may have seemed like a rare injury for a golfer, as most golf-related injuries involve the lower back, but knee injuries due to the golf swing are more common than you may think. In fact, the prevalence of knee injuries in golf is roughly 18%, with an even higher percentage when you only consider the elderly. Since most of these injuries are a result of overuse, it is important for golfers to understand why these injuries occur if they want to keep playing for years to come.
Read More: Knee Pain from Golf? Look No Further.Unlike traumatic injuries in high-intensity sports like football or basketball, most golf-related injuries are the result of overuse. As for the knee joint, there are multiple mechanical factors in the golf swing that contribute to overuse injuries. During the downswing, the lead knee rotates rapidly from a state of adduction (external rotation) to a state of abduction (internal rotation). This creates an abduction moment on the lead knee, which can cause ACL tears. The graph shows a plot of adduction/abduction moments on the knees during a golf swing, which was measured using force plates and retroreflective markers on golfers’ legs.
The magnitude (roughly 1 Nm/kg) is not large enough to cause traumatic stress on the ACL but is enough to potentially cause an injury over many repetitions of the golf swing. In addition to rapid rotation, the lead leg undergoes rapid extension during the downswing. The combination of these movements in large volumes over time can lead to other ligament tears or osteoarthritis. Osteoarthritis occurs when tissues in the joint break down over time.
In addition to these biomechanical movements, other factors like pre-existing knee conditions play a significant role in golf-related injuries. Over 30% of golfers with previous knee pain feel that golf has made their symptoms worse. The same is true for golfers with a previous total-knee arthroscopy (TKA), as nearly 34.9% experience pain after playing. Considering that golf is very popular among the older population, it is important to understand how to limit the risk of injury in the golf swing.
While the golf swing can lead to overuse injuries, there are a few preventative methods golfers can implement to protect their knees. Several studies recommend that golfers rotate their lead foot open (towards the target) by roughly 30 degrees. This decreases the stress on the medial (inner) side of the knee, a common area for osteoarthritis. Another adjustment golfers can make in their setup is how close/far they stand from the golf ball during the swing. Standing closer to the ball lowers the peak abduction moment on the lead knee, while standing farther away reduces the peak adduction moment. Depending on which area of your knee is in pain or has experienced previous injury, you may want to implement these adjustments to your setup. If you are experiencing pain on the inside of your knee, you should stand closer to the ball. Conversely, if your pain is on the outside of your knee, you should stand further away from the ball. Other preventative methods include warm-up stretching and regular exercise to activate and loosen the knee joint and surrounding muscles. If you’d like to learn more about these preventative methods, click here.