Why Are Dislocated Shoulders So Common In AFL?
With the footy season (finally!) starting up again this Thursday, what better time is there to write up the first blog post regarding footy for the year?
As you may know AFL is one of the most physical sports going around so there is no shortage of nasty injuries - and there's no reason to think this year will be any different...
One of the more common injuries you will see is the dislocated shoulder, I'll get on to the "why?" of that later. For those unsure what a dislocated shoulder looks like though, have a watch of the video below, as Gary Ablett Jr. injures his shoulder in a game a few years back:
(For those unaware, Gary Ablett was probably the best player in the AFL at the time. Think Lionel Messi in football, Lebron James in basketball, Wes Blackett in footy tipping!)
What is a dislocated shoulder?
A dislocated shoulder is essentially as the name suggests: a shoulder that is no longer located in the correct anatomical position. On the picture below you will see a picture of a typical shoulder, along with a normal looking X-ray:
In relation to the picture above, you should be paying particular attention to the head of humerus, as well as the glenoid cavity. The shoulder is a ball and socket joint which means it has a great range of motion but that does come at a cost - it is one of the least stable joints in the body.
Usually, the head of the humerus is head in place in the glenoid cavity by various ligaments around the joint as well as the rotator cuff muscles. There is also a cup of cartilage call the glenoid labrum which is used to provide additional stability to the joint.
When a shoulder becomes dislocated it is pulled out of the glenoid cavity and is typically associated with some level of muscle and ligament tearing. There are also instances when there can be additional injuries such as tearing of the labrum, or even a small bone injury.
So why do shoulder injuries occur so readily in footy? Essentially there are 2 movements which I am most wary of in terms of causing shoulder dislocations - the overhead contest to mark the ball, as well as the slinging tackle to the ground.
In both movements, the player typically has their arms raised above their head, either to mark the ball or to protect themselves from landing face first into the dirt. In this position, the shoulder is at its weakest anatomical position, and the muscles and ligaments in the shoulder are on a huge amount of stretch already. It only requires one uncontrolled, forceful movement to cause ligament tearing and bring the shoulder out of its capsule.
When a shoulder dislocates, it (typically) dislocates forwards and you will see what we refer to as the 'sulcus sign'. Essentially, there is a clear drop or ridge in the shoulder as it is pulled out the joint. You can see it on the video as Ablett comes off the pitch. You can also see he lands on an outstretched left arm, with another player's bodyweight piling on top of him. His shoulder has never fully recovered since this injury!
How do you treat shoulder dislocations?
The difficult thing with shoulder dislocations is that once you have dislocated it once, you have already severely injured the structural support of the joint. Recurrences of shoulder dislocations are as high as 80% in under 25's and typically around 20% in people overall.
That ligament support is something you wont get back unless your shoulder is really quite unstable in which case surgeons are able to tighten the shoulder capsule.
Most people though, respond well to physio that is focussed on several things: we want to improve the strength of the rotator cuff muscles that surround the joint. This looks to make up for the lack of ligament support by improving the structures providing stability other than the ligaments.
One of the most significant muscles to strengthen is called subscapularis - this muscle attaches from the shoulder blade to the front of the upper arm. By strengthening this up we are actually looking to improve the pull of the arm backwards, which helps to improve joint stability.
Another important part of rehab is to work on shoulder joint position awareness. When you injure your shoulder you start to lose a sense of where you shoulder is and you may unconsciously be putting your shoulder in positions that are unstable for the joint. This is one of the most important aspects of shoulder rehab!
If you have dislocated your shoulder, I would strongly recommend starting on a focussed rehab program immediately - this problem is one of those issues that the longer you leave it, the harder it is to rehab over time!
***If you see somebody dislocate their shoulder, and it doesn't naturally go straight back into place, send them to the hospital - your typical physio is unlikely to go near the joint until it has been relocated!***