Today’s post will look at a very common asymmetry that therapists see every day. A client comes in and you do a quick postural assessment, one shoulder sits higher than the other and we immediately note this on our chart .
I will not tell you to stop doing this but bear in mind that it is normal. It is called handedness and a right handed person will normally have a lower shoulder on their dominant side and a higher shoulder on the other side .
If you look further down the body often you will see a higher right hip and a pronated left foot . A weaker glute medius on the high right hip and stronger adductors on the lower left hip
If you would like to look a bit deeper into this check out Kendall muscle testing and function
Ok so you have finished your body reading static assessment and now it is time to do some manual muscle testing.You check internal and external shoulder rotation
Normally there will be a difference between the left and the right side. THIS IS NORMALL!!!
Right handed folk will have more external and less internal rotation and left handers will be the opposite. It makes sense if you go back into the shoulder history of your client.
If you did any form of sport growing up you will be more flexible into external rotation in your dominant arm.The action of throwing a ball, reaching back into a swimming stroke, a tennis serve, rowing and many other sports would contribute to this.You will be stiffer and less flexible into internal rotation because of the deceleration forces into internal rotation.
The most important factor that you should be looking at is the total range of motion of both shoulders.Often the shoulder that has less internal rotation will have more external rotation than the other one and visa versa.
Check this dudes external rotation!
A holistic look at the shoulder
When dealing with shoulder problems or just preventative care do not forget to look at the mobility of the hips.I will use the example of a Yogi trying to perform a warrior pose
If the back hip is restricted from performing internal rotation the leading shoulder will over rotate into flexion and external rotation to compensate for the hip.Of course this can lead to ankle and knee problems but believe me the shoulder can also develop problems because of the limitation of the hip.
Looks like a very dynamic yoga pose!!
A more dynamic example is a base ball pitcher, if this guy had a stiff left hip he would have to compensate in his lumbar spine with hyperextension and shoulder with hyper flexion,external rotation and early release increasing the torqe on the shoulder.
Shoulder external and internal rotation is different and these differences are perfectly normal. The most important finding that will drive your decision about whether to restore movement to a shoulder is if the total internal and external rotation is not equal or close to it.