Regional Interdependence - Why you need to think beyond the site of pain

As mentioned on this blog previously, it is increasingly common to see athletes reinjure themselves following discharge. Commonly this stems from the status quo in the world of rehabilitation, which is unfortunately commonly solely focused on the specific area of pain, with little or no consideration of the musculoskeletal anatomy that lies above and below. It is imperative that we as physiotherapists consider that there is interdependence on the whole region.

We use the term 'regional interdependence' to acknowledge that, in the human body, everything is related to everything. Regional interdependence refers to the concept that seemingly unrelated impairments in a remote anatomical region may contribute to, or be associated with, the athlete's primary complaint. I will highlight this concept by describing a classic and common example that I come across in my day-to-day practice.

I've lost count of the number of client's I have seen with a chronic right-sided lower extremity injury - be it an Achilles tendinopathy, plantar fasciitis, 'Runner's knee,' etc., with a concurrent restriction through their opposite thoracic spine - i.e. they present with limited mobility when turning their torso to the left. In simplistic terms, if we follow the fascial lines of the posterior oblique chain, we can trace the orientation of the muscle fibres of the right-sided gluteus maximus as they progress superiorly and medially (i.e. up and towards the midline of the body), connecting to the thoracolumbar junction (you can think of the thoracolumbar junction as a sturdy supporting structure in which a whole heap of muscles and tendons attach to). Continue in this direction and you will find yourself now on the left-sided latissimus dorsi muscle, which wraps around your thoracic spine, finishing at your left shoulder (see picture below).

Why is this important? When you make initial contact with the ground with your right foot whilst running (hopefully landing with your foot directly underneath - NOT in front - of your body), your pelvis is rotated in an anti-clockwise direction. To counteract this motion, your upper torso (thoracic spine) must rotate in the opposite direction (clockwise) to ensure that you project in a forward direction - and not deviating towards the left. Hence, a restriction in the amount that your thoracic spine can rotate will allow more rotation towards the left through your entire right-sided lower extremity when it is in contact with the ground. Running is a uni-planar sport - meaning that you essentially only move in one direction - forwards. Any extra rotation (or 'torque,' in biomechanics terms) through your lower extremity is going to place far more stress on the bones, ligaments, muscles, tendons, and cartilage than needs to be - eventually resulting in an overuse injury further down the track (no pun intended). If we look at the knee - it is primarily designed to bend and straighten (although, a very small amount of rotation can occur - but that is irrelevant in the current discussion). If your thoracic spine cannot counteract the rotation that occurs through your pelvis when running, your knee will bend on a slight angle. You can liken this to the analogy of a door on hinges. If you open and close the door normally, there is no issue. However, if every time you open the door, you grab onto the top of it and hang off it as it opens, the hinges are going to bend each time - eventually breaking. This is what is essentially happening every time you run if you have a restriction or limitation through your thoracic spine.

So what does this all mean, and what are the implications for us as physiotherapists as we move our profession forward in the near-future? I think we need to put much greater emphasis on the basic principles of screening our clients and athletes for pain, restricted mobility, stability and asymmetries in areas away from their presenting injury. In fact, this principle can be applied to athletes pre-injury. It's funny in the way that we go to the dentist every 12 months for a routine check-up, visit the GP every 6 months for a standard blood test - hell we even get our motor vehicles serviced annually - however, most people come to visit a physiotherapist once they have already sustained an injury. The take home message here is that most overuse running-related injuries are totally preventable, and can be identified sub-clinically (i.e. prior to the onset of pain) via a comprehensive physical examination coupled with a thorough patient history. Tools such as the Functional Movement Screen (FMS) and Selective Functional Movement Assessment (SFMA) are movements towards the right direction in challenging the status quo of the rehabilitation world from a 'cure' mindset to a more cost-effective 'prevention' approach. If something doesn't feel right - don't hesitate to make an appointment with a physiotherapist (preferably someone who likes to think 'outside of the square'), before a little 'niggle' turns out to be a full-blown injury sidelining you for months.