Written By: Mike Reinold
Original Story Posted Here: Does Reaching Behind the Back Reflect the Actual Internal Rotation of the Shoulder?
Photo from: https://webcampus.drexelmed.edu/skills/assessments/shoulder/shoulderexam.htm
It is no secret that I am not a big fan of stretching the shoulder behind the back to gain internal rotation. I have written about this in the past and even included it in my list of the 5 least favorite exercises. I received a lot of feedback for this opinion, both positively and negatively.
Many people agree with me that this is an aggressive stretch and puts the rotator cuff in an extremely disadvantageous position while many argued that it is still a position of function for their patients.
Apparently I am not the only one who has questioned this in the past as I have come across some research studies that assess if reaching behind the back (BTB) is an accurate measurement of internal rotation. This isn’t exactly the stretch that I dislike, but more of using the hand-behind-the-back technique to measure range of motion.
What Does the Research Say?
image Wakabayashi et al (JSES 2006) used electromagnetic tracking to assess the amount of shoulder internal rotation, extension, abduction, and elbow extension during this BTB movement. The authors report that the majority of internal rotation at the shoulder occurs before the patient reaches the sacrum. There is also a significant increase in shoulder extension and abduction to reach the sacrum. After the hand passes the sacrum, the majority of motion is achieved by flexing the elbow. After the hand passes T12, there is no significant increase in internal rotation. So it appears that getting to the sacrum is the key to this motion and that shoulder internal rotation, abduction, and extension can all limit the ability to get to the sacrum.
Mallon et al (JSES 1996) uses radiographs in healthy individuals to assess contributing motions and concluded that 35% of the BTB motion actually occurs at the scapulothoracic joint. They also agreed that elbow flexion was an important component of this motion and considered the BTB position invalid.
More recently, Ginn et al (JSES 2006) assess the validity of the BTB motion in assessing a loss of internal rotation in a group of 137 subjects with shoulder pain. The measured the BTB motion as well as standard goniometer of the shoulder IR at 45 and 90 degrees of abduction. The results showed only a low to moderate correlation between the motions, the ability to reach behind the back did not correlate to loss of active IR of the shoulder.
Ok so what does all of this mean? Here are my thoughts:
Reaching behind the back is not a valid measurement for internal rotation. The motion is created by the combination of scapula tilt, shoulder internal rotation, abduction, extension, and elbow flexion. Any combination of these factors will influence this motion.
Be careful when using a shoulder outcome scale that uses the BTB motion to quantify shoulder internal rotation. Unfortunately some do, including the Constant scale and the American Shoulder Elbow Surgeons (ASES) scale.
If you want to measure internal rotation of the shoulder, actually measure internal rotation of the shoulder. Grab that old goniometer out of the dusty drawer, it is actually pretty handy!
Don’t make treatment implications based on the BTB motion. For example, don’t perform posterior capsule joint mobilizations on a person just because they can’t reach behind their back.
Based on all of this, what about the person that has a limitation with this movement, what should we do?
I understand and agree that this is a position of function.
I still recommend avoiding this as a stretch. I have never had good outcomes and I really believe you are putting the shoulder joint and rotator cuff in a terrible position. I talk about this in more detail in these past two posts on my 5 least favorite exercise here and here.
Use the information from these studies to explore why a person doesn’t have good BTB motion. Assess the scapula, shoulder extension, abduction, and elbow flexion. Don’t just assume it is all IR.