Rotator Cuff Injury
Work Ergonomics
July 16, 2020Rotator Cuff Injury
Rotator Cuff Injury
“I think I’ve hurt my Rotator Cuff” is one of the single most common phrases uttered in physio clinics everywhere. We’ve certainly had a procession of patients coming through City Physio of late citing their dodgy rotator cuff as being the bane of their existence. This isn’t necessarily a true reflection of the prevalence of rotator cuff injury in the general population however so why does the rotator cuff get such a bad rap? Martin Place is full of people who spend plenty of time at a desk and then offset their lack of mobility with a frantic 45 minute workout with very little prep work. Need I say more? Probably not, but let’s get into the nitty gritty of shoulder pain and what may actually be happening anyway.
First of all, it is highly unlikely you have ‘damaged’ your rotator cuff if you have an absence of trauma, that is if you haven’t fallen over and landed awkwardly, got tangled up in a rugby tackle, or lost control of that heavy dumbbell while throwing weights over your head. Sure, there is a subgroup of people we see who have rotator cuff tears which are atraumatic purely because they’ve lived, That’s right, ageing is a large predictor of rotator cuff tear. BUT fear not! Most degenerative cuff tears are completely asymptomatic and people would have no idea that it even exists. Less commonly younger people may have the tendency to compress their cuff if they have a funky anatomical variance- or what we call a hooked or curved acromion.
Okay, so if you haven’t damaged your rotator cuff then what on earth is going on? Well… the shoulder girdle is a complex area which requires an in depth assessment to identify the primary impairment creating stress in the joint. This commonly presents in the form of impingement or mechanical compression in various parts of the joint. Optimal shoulder movement relies on your ability to coordinate the humerus (upper arm bone), scapula (shoulder blade), clavicle (collar bone), and the ribcage (which has 113 joints in total). Sounds pretty simple right?
Now let’s consider the glenohumeral joint or where the head of humerus articulates with the glenoid, basically a ball in a socket. Now this ball and socket resembles a golf ball on a golf tee from a relational size perspective. The primary aim of shoulder coordination is to keep that golf ball as close to the centre of the tee as possible while rotating the ball up to 120 degrees (the other ~60 degrees of shoulder range comes from the shoulder blade rotating around the ribcage). The primary contributor to this stability through range is (yep, you guessed it) the rotator cuff. The rotator is comprised of 4 muscles which attach on the back (infraspinatus & teres minor), front (subscapularis) and top (supraspinatus) of the shoulder blade which all co- contract as soon as we start to think about initiating movement preventing any unwanted translation in the joint.
Rotator Cuff Treatment
So where does it all go wrong? One of the major things we see contributing to dysfunction at the shoulder girdle are postural inadequacies. Think of your typical office worker slumped in front of a desk all day. Head sitting forward, chin poked out, exaggerated curvature in the upper back, shoulders rolling down and forward. The tissues in the human body basically adapt to the forces that are placed on them so if we spend too much time in one position then we are going to have the tendency to migrate into that position moreover increasing the dominance in a select group of muscles relative to the muscles opposing their action. Most of the joints in the spine are synovial which means they’re contained within a pouch and self lubricate on the provision that they move regularly. Now, if we’ve made it harder to find those little muscles that help us get nice and tall and we’re working against joints which are a little resistant to sliding backwards, where else can our shoulders go other than forward? Forward tilt of the shoulder blade will put the muscles at the back of the shoulder on length which inhibits their ability to co- contract with the muscles at the front of the shoulder. Muscles are much happier working at mid range than when stretched. If we have less drive from the back of our shoulder the golf ball slides forward decreasing the space available to move in the shoulder joint. This is only exacerbated by moving your arm into more complex ranges or into end ranges where muscles which are short and tight don’t allow for full pain free translation of the ball in socket.
So yes, there is a rotator cuff component to a lot of shoulder issues but it is not always the primary driver of dysfunction, it can merely be the victim. If the cuff has been compressed and irritated the body will be less inclined to load up on the affected tendon creating somewhat of a vicious cycle. Addressing shoulder problems is about creating an environment which will optimise muscle activation and preserve space in the joint. It usually involves a brief period where activity is modified to reduce symptoms while implementing cues to improve posture and rib stacking, ensure muscles which move the shoulder blade remain active, and retain strength in the rotator cuff in non- aggravating positions. This is quickly progressed into further range and functional movement to allow you to achieve your goals no matter what they are.
As the gyms around Martin Place start to fill back up and people start asking more of their bodies on top of a lower baseline of fitness this is sure to be one of the major things we see. Start slow, focus on form over force, and if you have any niggles give City Physio a call and we will ensure you’ve addressed that niggle before it becomes an injury.
Matthew Hagerty
