Looking at shoulder health from a wider perspective

The shoulder complex is one of the most undernourished areas of the human structure. There is great kinetic potential within this powerful area of architecture, and it is crucial that when we are rehabilitating shoulder injuries or upper limb injuries and developing physical conditioning and sports performance strategies, that we take into account the true integrated nature of the shoulder within the wider ecosystem of the human body. Common injuries such as rotator cuff tears, frozen shoulder, restricted range of motion either from underused or equally inefficient overuse, must take into account the wider nature of how the shoulder complex and entire body function as an integrated structure.

In the field of injury rehabilitation and treatment of shoulder injuries, there are many ways to approach the reconditioning of a shoulder. The more traditional, specific muscle activated motor control drills show reduced efficacy for long term benefits for shoulder health. Postural adaptations and ingrained movement patterns that have been built up over long periods of time are not easily changed by conscious control and isolated exercises. We also have to take great care in understanding what biological plausibility there is in the rehabilitation and performance strategies, and the functional carry over of these approaches in real world movement situations. From a neurological perspective, higher-order structures within the brain and the central nervous system have a propensity for more compound movement synergy rather than that of individual muscle control. So in order for us to maximize the function of the shoulder, we must provide a strong biofeedback system in order to shape and create multi-dimensional diversity in the movement potential of any shoulder complex. The same argument has been made in regards to spinal stability; that no single muscle plays a dominant role in the process of spinal stability and that the contribution of individual spring-like guide wires constantly change and adapt depending on the movement based task at hand (2,3). I believe that the same may well be said for the shoulder complex.

When looking at the shoulder, we should ask ourselves first; “What does it do and why…?” Examples such as throwing, climbing, hanging, swinging all intimate that the shoulder complex has a natural, inherently powerful elastic structure that serves the upper limb as it connects it to the thorax. Attached to 17 muscles, the overall role of the shoulder blade (scapula) is to transfer power and be suitably conditioned for high quality coordinated motion, maximizing the overall degrees of freedom needed to place the hand in space through the shoulder joint (1). The scapula itself is suspended in a ‘tensegrity’ based web-like network, allowing great power generation and range of motion capacity, whilst simultaneously creating a stable environment throughout multi-variable motion. If we use the analogy of a bicycle wheel, the scapula acts as a compressed yet mobile central hub, whilst the spokes that attach to the hub represent the musculature that suspend the scapula, creating a web-like muscular suspension mesh work. Each spoke in a bicycle wheel is constantly sharing the load and acting in concert, each muscle that attaches to the scapula represents these wire spokes.

Therefore, rather than viewing the scapula as a structure that should be a restricted, over-stabilized base, a common misconception with shoulder rehabilitation strategies, we should appreciate that the innate elastic properties and stiffness of the muscular structures in which the scapula connects, enables this sling like muscular connection to efficiently facilitate the absorption and transfer of kinetic energy throughout the entire structure of the human body, all the way from upper to lower limb through the main central axis of the body. We have to harness this potential, understand the condition of any given shoulder, it’s current structural capacity and level of coordination to choose a starting point as to how and where this potential can be explored and developed for injury rehabilitation, athletic performance and longevity of the shoulder joint itself.

References:

1. McQuade KJ, Borstad J, de Oliveira AS. Critical and theoretical perspective on scapular stabili- zation: what does it really mean, and are we on the right track? Phys Ther. 2016;96:1162–116
2. Cholewicki J, McGill SM. Mechanical stability of the in vivo lumbar spine: implications for injury and chronic low back pain. Clin Biomech (Bristol, Avon). 1996;11:1– 15.
3. McGill SM, Grenier S, Kavcic N, Cholewicki J. Coordination of muscle activity to assure stability of the lumbar spine. J Electromyogr Kinesiol. 2003;13:353–359

Kris R.