Your shoulder evolution and why you may be hurting it more!

Your shoulder evolution and why you may be hurting it more! – Ryan Yang

Ryan is a physiotherapist at Physio-Logic. His disciplined nature means he is regimented, trains often and audits us constantly to make sure we are consistently keeping our practice evidence based. However, his banter-ful nature balances him out well. I have invited him to do a little story telling on the brief history of humankind!

When early humans came down from the tree in the savannahs of Africa some 6-7 million years ago, a few biological changes happened in the shoulder that made it possible for our ancestors to survive our harsh environments. The evolution and development of our pectoral muscle fibres evolved from a vertical orientation to horizontal are one of such adaptations. This change diminished our ability to climb trees but made us incredibly proficient at bench press (*ahem*), I mean throwing ;-). Along with transformation in the shape and orientation of our shoulder blades and thorax, the human shoulders unlocked the single most significant military intervention in history – ranged attack, turning our species into the most dominant predators on earth.

This change diminished our ability to climb trees but made us incredibly proficient at bench press (*ahem*), I mean throwing

We are capable at throwing projectiles at unmatched speed and power, despite being significantly weaker than most other primates like chimpanzees. Baseball pitchers and javelin throwers are some of the best display of this uncanny ability. This extraordinary power and precision is achieved by cocking their arms all the way back, storing elastic energy like a slingshot and consequently catapult projectiles forward upon release. The further one can cock their arm back, the more energy is stored in the shoulder, and faster and further one can throw. Therefore the mobility of the shoulder is closely connected to its function and performance.

A number of things can go wrong; whether it is from overuse, underuse, postural misalignments or acute traumas… This complexity also makes the shoulder one of the most difficult joint to assess and diagnose clinically.

Such mobility is made possible because the shoulder joint is a “ball-and-socket” joint, similar to the hip. Unlike the hip, the “socket” in the shoulder is rather shallow and the “ball” is proportionally bigger, which allowed a greater range of movement, but also means the shoulder joint is inherently unstable and more susceptible to injuries. There are more than 20 muscles directly connected to the shoulder complex, directly and indirectly, all of which need to work in harmony to ensure that the shoulder joint is properly positioned. A number of things can go wrong; whether it is from overuse, underuse, postural misalignments or acute traumas. This makes shoulder pain and dysfunction one of the most common conditions we see clinically as physiotherapists, especially in the athletic population. This complexity also makes the shoulder one of the most difficult joint to assess and diagnose clinically.

If you follow any fitness gurus on social media, you would be overwhelmed by the many different shoulder rehab/prehab exercises they post. You would also end up diagnosing yourself with a dozen different conditions. WARNING: if you are doing this, stop. Self-diagnosing can be unsafe or even dangerous. The chances of over-compensating by ‘retraining’ the wrong set of muscles can throw your shoulder into further realignment, or even worst, into permanent damage like a tendon tear or God forbid a condition like rhabdomyolosis.

Seek professional help if you are experiencing prolonged pain and dysfunction with your shoulder. Our value as physiotherapists is more so to assess and identify specific shoulder problems, and then we can prescribe you with an individualised rehab programme or point you in the direction of your favourite shoulder guru video clips. Because musculature plays such an important role in the stability and function of the shoulder, exercise based rehab has been proven to be the most effective modality when tackling shoulder problems. In saying that, let us add our magic touches to prime those muscles so that it will work the most efficiently.

With love, Ryan.