MOBILITY OVER STABILITY
The upper limbs are crucial. They help us to explore the world, allowing us to reach, pull ourselves up, push open doors and save ourselves if we fall. Without even thinking about it we use our upper limbs to carry out hundreds of different tasks each day. Perhaps it’s no surprise then that a lack of shoulder stability is a common issue.
To explain the shoulder in a little more depth, it’s a complex system comprising three joints and three bones: the humerus (upper arm bone), the clavicle (collarbone), and the scapular (shoulder blade). The size of the humeral head (the bulbus bit of the bone at the top) is approximately the size of an orange and the surface it articulates on is the size of a 50 pence piece. So how does the large humeral head (the orange bit) refrain from slipping off or falling out from the small 50p-sized joint surface?
Well, firstly, there’s a really cleverly designed rim known as the labrum. The labrum increases the surface area of 50p and two muscles (and a group of muscles collectively referred to as the rotator cuff) hold it in place. Additionally, a membranous cover (called the joint capsule) which surrounds the 50p also helps to hold everything in place. As well as this there are liquid filled sacks called bursa which aim to reduce friction between the muscle tendons and the bones. A miraculous combination of all of the above working together results in the shoulder being quite an extraordinary apparatus!
CAUSES OF SHOULDER PAIN
With so many different components working simultaneously to make our shoulders function, it’s understandable that problems can occur. Linked to the anatomy described above, some of the most common difficulties include:
1. The rotator cuff tendons can be overloaded and become problematic (they can swell, thicken and eventually degenerate). This problem is referred to as “tendinopathy”.
2. The rotator cuff can tear, often due to acute overload. This doesn’t always mean lifting a heavy weight but can happen with things like gardening or putting flat-pack furniture up with the wrong tools.
3. The bursa (those fluid filled sacks that reduce friction between the tendons and the bone) can become inflamed due to an occurrence such as a fall.
4. The joint capsule (the cover round it) can become inflamed and contract causing what is known as a “frozen shoulder”. A frozen shoulder goes through a number of stages of pain and stiffness before eventually resolving and the condition is much more prevalent in women than in men. It’s seen most frequently in females above the age of 40 and although there are a few theories for this, the medical world is yet to agree on exactly why this is the case.
5. A break, fracture or dislocation to the bones/joints. Skiing season means we see a lot of impact fractures (referred to as Hillsachs lesions) to the humeral head due to patients falling onto the shoulder, elbow or an outstretched arm. If you’ve taken a fall onto hard ground whilst skiing or playing another sport and your shoulder pain continues, get it checked by your GP or physiotherapist. An X-ray may be necessary to rule out a Hillsachs lesion.
Less frequent problems include:
6. Arthritis in the joints. Arthritis can occur in the main joint between the humerus and acromion, the acromioclavicular joint or the sternoclavicular joint. What a mouthful! Best to get checked out for an accurate diagnosis on this one!
7. Referred pain from the neck. This is most commonly seen in patients who have problems with organs, such as liver disease or duodenal (small intestine) which can cause right shoulder pain. Slightly less commonly experienced is referred pain under the right shoulder blade which is the result of gallbladder or gallstone issues.
8. The big C. Cancerous tumours can cause shoulder pain, but again, thankfully, these are extremely rare.
As you can see there are a number of structural and functional problems than can cause shoulder pain. Shoulders are complex, so don’t be tempted to self-diagnose. It’s important that to arrange a thorough examination with a GP or physiotherapist. At W5Physio, we will ask you lots of the right questions, plan a physical examination and recommend any further investigation such as ultrasound imaging, X-rays, MRI or CT scans. If in doubt, come and get checked out!