Shoulder pain is incredibly frustrating, I get it, I’ve had a few minor episodes of shoulder pain and it isn't fun, let alone suffering a shoulder injury like a
dislocation or a labral tear. Research suggests that up to 67% of people suffer shoulder pain in their lifetime and it doesn’t seem to get less common as we get older. People older than 50 most commonly report episodes of shoulder pain. So why do so many people get shoulder injuries? Is it because we use it so much, maybe because it’s such a mobile joint, or are we unlucky? I think it’s a combo of the first two, with a hint of number three on occasions.
Because the shoulder is required to perform movements with such a variety and such a large range of motion, we need to have a shallower joint socket with more of an active stability system aka the rotator cuff. The rotator cuff works to dynamically stabilise the humerus within the shoulder joint through movement. What happens though if our rotator cuff gets a little weak or a little under-used, or if we try to do a little too much too quickly? This is often where we run into trouble. Acute injuries such as a dislocation or rotator cuff tears can occur with more one-off acute traumas such as a traction force on the arm, falling onto an outstretched arm, or catching or lifting a heavy object. Shoulders are incredibly mobile and, on occasions, unstable structures in the right positions and under the right load can cause big problems. Keep your shoulder strong and keep everything around it mobile and you’ll do your best to keep a healthy set of shoulders.
Shoulder pain can be incredibly diverse ranging from acute to chronic rotator cuff tears, to AC joint sprains and shoulder dislocations requiring surgery. As a physio, the shoulder is always keeping me on my toes with what could go on. Sometimes shoulder pain isn’t even caused by the shoulder, on occasions, it’s caused by the cervical or thoracic spine. All I know is it takes time to determine an appropriate diagnosis and treatment pathway.
The shoulder joint is one of the more complex anatomical structures, particularly when looking at it from a functional perspective. The joint is a ball and socket joint, with the humerus sitting within the glenohumeral joint. It is the articulation between the scapula and the humerus. The head of the humerus is significantly larger than the glenoid fossa which it sits in, this is what enables it to have such a wide range of movement.
A large range of ligaments supports the joint whose role is to help stabilise the shoulder. The main supporting ligaments are the glenohumeral ligaments, and the coracohumeral, transverse humeral, and coracoacromial ligaments.
Between the tendons overlying the shoulder joint and the underlying structures are bursae, these are small synovial fluid-filled sacs which aim to reduce friction. There are two within the shoulder joint, the subacromial bursa, and the subscapular bursa.
The rotator cuff muscles attach onto varying areas surrounding the shoulder joint to provide active support and stability to the shoulder joint through different functional activities and movements. The muscle group works together as a group rather than as singular muscles like the quadriceps do to extend the knee. Think of the rotator cuff more like an orchestra playing as one large group rather than just singular instruments playing on their own.