Estimates from the Australian Bureau of Statistics 2014–15 National Health Survey show about 3.7 million Australians (16% of the population) have back problems. It is estimated that 70–90% of people will suffer from lower back pain in some form at some point in their lives.
We are all definitely improving our treatment and prevention strategies for lower back pain: physiotherapy treatment (joint mobilisation/manipulation, soft tissue techniques and myofascial release, neural tissue mobilisation, dry needling, taping, real time ultrasound imaging to assess core stability muscles and clinical exercise prescription), applying heat/ice, consuming suggested medications, exercise performed on a consistent basis, adopting sit to stand desks at the workplace, taking the stairs instead of the lift, parking further away from work and the list, which is different for every individual, goes on!
There is marked attention delivered to the lower back, but do you ever think about the platform your lower back sits on?
It’s like trying to fire a cannon from a canoe.
It’s all well and good to develop a strong core to address your lower back but if you do not have a strong, stable set of feet for your back and pelvis to sit on, then you are not optimising your injury prevention!
The foot, comprised of 26 bones, 33 joints and over 100 tendons, muscles and ligaments, is an engineering masterpiece, creating and controlling movement. Before man-made, flat surfaces were created, the muscles in our feet were constantly challenged by unpredictable, uneven and undulating surfaces, allowing strength and endurance to be kept optimal. This, combined with the fact that most of us wear shoes that do not allow the natural movement of the foot to occur so easily (see below), means that the function of the foot is altered, hence creating extra stresses on our lower backs!
The windlass mechanism is a mechanical model that describes the manner by which the plantar fascia supports the foot during weight-bearing activities. When we walk, as our toe “pushes off”, the foot should become a rigid lever to propel us forward. As the leg swings forward and the heel lands (heel strike), the rigid lever turns into a shock absorber by splaying to dissipate force.
If your footwear does not allow this, the ground reaction forces can be transmitted up to the lower back. Similarly, if the muscles that are responsible for supporting the arch of the foot are weak, this will also allow these “ground and pound” forces to head straight up to the lower back!
One study (3) showed that “low back pain patients with foot pronation displayed a higher vertical ground reaction force as well as higher loading rate”.
So what can we do to lessen these forces that are heading straight up into that lower back?
Mobilise and strengthen your feet!
Foot mobilisation can be done, sitting with one foot over the other knee (or in a position you find most comfortable). Simply pretend like you are breaking up tension in your feet by grabbing the feet with both hands and moving through each little joint in the foot. Self-massage is often recommended as well as releasing tension in the bottom surface of the foot with a small ball.
Remember, your physiotherapist can prescribe exercises clinically, specific to your injury and biomechanics.
“Intrinsic” exercises are often performed to strengthen the “core” musculature of the foot. Often, these exercises involve splaying the foot wide, followed by lifting the arch of your foot using the arch itself. Your physiotherapist can determine specific sets and repetitions and show you how to perform these exercises. Specific strengthening exercises for your lower limbs is also recommended, which, once again means that the ground reaction force is dissipated through these muscles and not your back!
Walk around on the sand and grass in bare feet and squeeze the sand and grass as you do it! Patrick McKeon, a professor at Ithaca College’s School of Health Sciences and Human Performance in New York, says that the more people go barefoot at home, in the office or outside, the healthier their feet will be. The researcher explained the importance of this by describing the cycle of feedback between the large “extrinsic” muscles in the legs, the smaller “intrinsic” muscles in the feet, and the neural connections that send information from them to the brain. When this muscle balance is flawed, then your lower back muscles have to work harder to support you, hence more stress to the lower back!
We know there are populations out there who experience a significant reduction of lower back pain and disability with the use of custom made orthotics (4). The right insoles can definitely help to relieve lower back pain by assisting the foot through its optimal mechanics and by absorbing those nasty ground reaction forces!
As physiotherapists, we always see a sudden influx of lower back pain presentations in the clinic as summer approaches. As we question if patients have done anything different in their daily routine, often they cannot find an answer, other than to note that they have spent more time in thongs or out of shoes all together. This just signifies the positive impact that a good pair of shoes has on your lower back and also stresses the importance of mobilising and strengthening those feet, so when the shoes come off around bbq season, you don’t have to see your physiotherapist for that niggling back!
Written by Lauren May
Director and Principal Physiotherapist
South Perth Physiotherapy