Most of us have experienced shoulder pain at one time or another, especially as we get older. Usually it is nothing more than a minor inconvenience, but sometimes, it can be an indication that all is not right with your body, especially if it is left shoulder blade pain.
The human shoulder is a marvel of engineering. It is a ball-and-socket joint which means it has an incredible range of motion in 2 axes. In fact, it’s range of motion is only limited by how far the muscles and tendons can stretch. Along the sagital plane (front to back), the shoulder has a full 360° range of motion. Along the frontal plane (towards and away from the body to the side), the shoulder can have up to 270° of motion. The average for the frontal plane is around 200° of motion. The shoulder (also known as the Glenohumeral Joint ) is made up of the head end of the Humerus, which is the upper arm bone and has a ball at the end, called the Capri Humeri. This fits into (or articulates with, as we like to say) a shallow socket at the apex of the Scapula, or shoulder blade, called the Glenoid Labrium, hence the name Glenohumeral Joint. Extra stability and support is provided by the Clavicle, which is joined to the Scapula by a ligament. Four muscles provide stability and movement for the entire joint, known as the Rotator Cuff muscles. From top to bottom (or superior to inferior in Medicalese), outboard to inboard ( or lateral to medial), and front to back (anterior and posterior), they are: Subscapularis, Infraspinatus, Supraspinatus, and Teres Minor. There are several tendons anchoring the muscles to the bones, several ligaments that join the bones, and a fluid-filled sac called the bursa which cushions the joint and keeps the ends of the bones from rubbing together (that would really hurt, as anyone who has had bursitis can tell you….).
With all these parts having to work together, it is easy to see how things can go haywire from time-to-time. Stretching a muscle, or tendon too far can certainly slow you down considerably. And stretching or tearing a ligament can be downright crippling. But it gets worse. There are many parts of the body that do not have as many nerves with pain receptors running through them, so they have to ‘borrow’ them from somewhere else to send pain signals to the brain. What this means is that, even though you feel pain, the actual cause may be some distance from where you are feeling it. This is known as referred pain, and can indicate some serious health issues, especially when it is on the left side.
Fortunately, the most common causes of left shoulder blade pain are simple strains, and an occasional fracture to the scapula. These are easily treatable, and usually heal with no further issues. Bursitis, an inflammation of the bursa caused by repetitive motions or injury, can also cause pain in the shoulders, and is also easily treatable with 100% recovery. Some of the more serious things that can cause pain in the left shoulder are cardiac events (commonly known as heart attacks), problems with internal organs, or cancer. If left shoulder pain is accompanied by chest pain, it could be a cardiac event, and you should see a doctor as soon as possible. If the shoulder pain is accompanied by abdominal pain, it could be a problem with an internal organ, and again, you should see a doctor as soon as possible. If the left shoulder pain is accompanied by upper chest pain, it could be a Pancoast Tumor ( we used to call them suclus tumors), which is a type of lung cancer. It is generally malignant, so it is important to see a doctor for early detection and treatment. And lastly, left shoulder pain can be caused by arthritis, in which case all you can do is learn to live with it.
Anytime you feel left shoulder pain, and do not know why, you should see your doctor. Physicians have the training and equipment to make a correct diagnosis, and formulate the best treatment plan.
Good health to you.