Rotor Cuff or a Cuff that Rotates

Updated: Jun 29, 2020

By DARREN GLENDENNING APA SPORTS PHYSIOTHERAPIST


Commonly mis-said, a proper functioning ROTATOR CUFF is crucial to normal pain-free shoulder movement. So what is the rotator cuff & why is it's proper functioning crucial?

It wasn't until recently that I discovered first hand, what it was like to have a sore shoulder (and no, this is not my shoulder in the picture above) that stopped me sleeping on my right side and prevented me from doing certain activities (including hanging out the washing - which may or may not have been true). After I recovered from the shock that a Sports Physio wasn't impervious to injury, I sat and reflected on my sore shoulder. To cut a long story short, I had a minor right shoulder injury (which I basically ignored) approximately 6 months earlier that gave me intermittent pain for about a week. It completely resolved until this actual episode of soreness began. What I found on examination (of myself), was a very weak (with poor control) right subscapularis muscle (one of my rotator cuff muscles). This weakness may have been caused by direct or indirect influences from the initial injury 6 months previous. What's important though, is that a targeted, functional strengthening program over the proceeding weeks, normalised the balance around my shoulder and best of all, took away the soreness. I'm back doing the things I love, although the shoulder may never be up to hanging the washing again! Physios orders!!


The next part of this blog I add with trepidation! If you're keen to immerse yourself in some fairly simple medical jargon & explanation (which may send you off to sleep) on the what, why and blah blah (as my wife proclaims) regarding the rotator cuff, please read beyond the 'blah blah' line below. If not, just leave knowing that shoulder pains are fixable. If you have ongoing shoulder pain, see a Physiotherapist who has experience dealing with shoulders and find one who really cares about finding a solution for you!

The rotator cuff is the collective term for a group of 4 muscles (remember, these contract) that originate from the shoulder blade (scapula) and attach, via their flat, strap-like tendons, to the upper arm long bone (the humerus). These tendons encapsulate the ball & socket joint (coloured green in the picture below), like grasping your right hand over your left fist. From the front of the joint we have the Subscapularis tendon (or 'Subscap', with the muscles direction of pull depicted by the blue arrows in the diagram), from above the Supraspinatus tendon (not pictured) and from behind the Infraspinatus & Teres Minor tendons (not pictured). They have a vital role, helping to hold the ball centred in the socket, preventing impingement.

As you can see in the diagram, the line of muscular pull of our main muscle that lifts our arm up from our side, the deltoid, is directed upwards (red arrows). If the deltoid was the only muscle available to us to lift the arm, the ball would be driven upwards into the bony ceiling above (the acromion and collar bone pictured where the deltoid originates), pinching & squashing soft tissues (impingement) such as the supraspinatus tendon & the subacromial bursa. Lucky for us, our shoulders don't normally operate this way! The muscular pull of the rotator cuff muscles (only one of the rotator cuff muscles is depicted in the picture above by blue arrows) help to compress the ball into the socket and direct the ball downwards, overcoming the upward pull of the deltoid, allowing the ball to pass safely underneath it's bony ceiling (the acromion). This is a very simple explanation regarding the very complex interplay of over 20 muscles involved in elevating the arm. For most of us, we're not even aware of this happening. We happily take it for granted until things go wrong!



A painful shoulder can arise after injury, overuse or general wear & tear. With regards to tears in the rotator cuff tendon, not all tears are created equal! Yes, imaging, such as ultrasound & MRI, may find a tear, but is it the primary source of your symptoms. Research shows that atraumatic (without trauma) rotator cuff tears are commonly found in people who don't have shoulder pain (called the 'kisses of time'). This is where an experienced physiotherapist can assess and differentiate, what is in fact causing your symptoms. Is it a tear, a recent trauma, an unfit shoulder, referral from the neck or compensatory strategies that have surpassed their use-by date from a past injury (to name a few) that are causing the issue. If you're having issues with your shoulder, maybe it's time to see someone who cares and formulate a treatment plan!

30 views0 comments

Recent Posts

See All