What are force plates?
3D Force Pressure Assessments are a modern podiatry approach which we use here in the clinic!
The plates measure the pressure going through our feet as walk. The scans show areas of high and low pressure which guides our treatment to get our clients out of pain. Doing this assessment we can determine any problem areas in the way we walk or our biomechanics, which may be relating to aches, pains and even skin conditions.
How does a force plate help with foot pain?
Force plate assessments aid in Podiatrists making a diagnosis of certain conditions involving the lower leg, ankle and foot. Using this tool can be super useful to determine the cause of someone’s problems. The scans will highlight any difference in pressure between feet, and will focus on the four key observations; asymmetry, stability, gait progression and speed.
There are two types of force plate scans, static and dynamic.
Static scans show where the pressure is distributed when standing in one spot and can give us clear indications of where most of your force is on the foot or whether there are any imbalances between sides. We can see discrepancies in limb length pressures here too.
Dynamic scans give us clear understandings of how the foot moves when we walk. We look at symmetry, stability and your gait progression line here. The dynamic scan will often show very clearly and overload of the painful area, or a compensation pattern that is leading to the overuse of the painful area.
Conditions we treat using the force plate
The force plate is a great tool in helping us diagnose some conditions or assists us in making clinical decisions as to what the best treatment is for our patients.
Some of the most common conditions we treat using the force plate as a guide are:
In most cases of heel pain on the force plate there are often high areas of pressure through the medial (inner) aspect of the heel. The pain experienced from plantar fasciopathy (or plantar fasciitis), is often directly on this part of the heel bone. Through walking mechanics of a pronated (rolling in foot) or an foot that is rotated outwards this can commonly place extra pressure onto the inside part of the heel bone.
Using the information found here, the treatment plan may include recommendations footwear or make custom orthotics, we can use information from the force plate to help guide us in those decisions. Other helpful treatments including shockwave therapy, dry needling or soft tissue therapy will be used concurrently to help ease pain fast.
As seen in the below image, we can see (in the red) a large amount of pressure going through the center of the heel, this would correlate with any sort of heel pain, as there is a lot more pressure going through this area when walking.
Forefoot pain is another condition we see often as podiatrists. This type of pain can range from:
As seen in the image below, we can clearly see a high area of pressure locally under the 2nd and 3rd toes on the ball of the foot. This can correlate to more loading through this area which could flare up any of the above listed conditions. It can also be helpful in determining where and why people develop things like corns or calluses, because they are formed in the higher areas of pressure.
The gait progression line in this scan also reflects a kink in the line at the forefoot, which reflects a pressure change and rotation that is happening in gait. Forefoot pain is very common when there are quick rotation changes in gait through the hip, knee or foot, which reflects that more force through the forefoot zones.
Interpreting the force plate: A case study
On this image here we can start to pick apart a few things which may become or be a current problem in this foot. This client is experiencing right sided heel pain.
- There is minimal pressure going through the middle part of the foot – to me this would suggest this is a neutral to high arch foot as the midfoot is not contacting the ground
- The red line on the base of the heel of the right foot starts slightly more to the middle part of the foot or medially meaning there is increase loading or pressure at the plantar fascia, possibly increasing the risk of plantar fasciitis or fasciopathy
- At the ball of the foot there is a lot of redness or pressure around the 2nd toe joint, ideally most of the pressure should be focused around the big toe joint. This may relate to corns, callus or pain around the ball of the foot as there is increased pressure on that smaller toe joint. The gait pressure link reflects a kink here too, showing more pressure at this particular area of the 2nd joint.
Changing pain and pressure
One of the most useful features of the force plate is when we do testing, then treat our client with strapping, then perform re-testing afterward treatment. It is a great tool that can give us some visual feedback to see whether we have not only improved gait, and also if we have reduced high areas of pressure from the foot.
For example, when we tape the foot, we are often trying to change the way the foot functions and offload painful areas. Once the foot is taped, we often get clients to walk on the force plate again, typically we will see a change in pressure under the foot alongside a reduced amount of pain.
Using technology to Guide our Treatment
The force plate is a great tool that we as podiatrists use to help guide us in determining what condition you have and why it is there. This helpful technology gives us a clear understanding of what is happening within the foot, that may otherwise be unclear to see with the naked eye.
The force plate is great for determining how much control an orthotic should have on your foot. For example in our case study above, if a lot of pressure is present medially in your heel, then that tells us we need more medial support to counteract this force your body is applying to the foot. Also with pressure under the second toe it is very simple to add padding here to reduce pain and deflect joint overload.
The force plate also helps guide us in terms of strength training. Often we see people with quite weak calves. This can be determined when we see things like, too many of your lesser toes on the plate. Basically when we see your lesser (smaller) toes besides your big toe on the force plate, it shows us your calves are not working hard enough or are stronger enough to support you during gait as your other ankle plantar flexors (the muscles that push your foot downwards) are overused.
What is next?
If you would like to have your foot pain assessed by one of our Adelaide Podiatrist, book online or call the clinic (08) 7226 9901 to organise your appointment!