Thursday, November 12, 2009
Hip Internal Rotation Evaluation
Internal hip rotation is a crucial component when it comes to proper sprinting and athletic performance. It also plays a significant role with healthy backs. Normal internal rotation for the hip is around 45 degrees. In most really good sprinters, it tends to be a little more, in the athletes I've evaluated.
So when your checking for this one thing to keep in mind is what can inhibit this motion. The number one obvious culprit is tight or short external rotatores of the hip. These smaller muscles, that lie under the glute max can exert a strong pull on the hip, limiting the motion. Another less obvious soft tissue problem is tight psoas/adductors. These muscles when tight together, will have a combined vector pull to inhibit internal hip rotation.
The motion when lacking, will cause an increase demand on the glute medius eccentrically. So doing all the glute med rehab exercise will be like hitting your head against a wall, useless. Fix the problem, don't patch it. Not only will the glute med become overworked and inhibited, the piriformis will now take on a much larger roll and become hyperactive. This will place more stress on the sciatic nerve.
The most common predictable common factor in low back pain is lack of internal hip rotation. This is part of the biomechanical arsenal of things I always check on my patients in Grand Rapids. They have done many studies that have linked low back pain, SIJ problems with greater external rotation. So again, the importance of hip internal rotation, can not be stressed enough. Here is a link from Mike Reinhold, that lists several studies that have been done with hip rotation. http://www.mikereinold.com/2009/03/low-back-pain-and-hip-motion.html