To understand plantar fasciitis trigger points, you have to imagine the foot is made up of arches. The most important arches are between your heel and your toes. And the keystone of the arch is the navicular and the talus bones, with the heel bone on the one side and the metatarsals coming down the other side.
If you imagine that arch as a bow, then the string of the bow is the plantar fascia. The plantar fascia spreads out, and has five slips that attach to the metatarsal heads (these are bones of the foot.) As it comes back across in the sole of the foot, it narrows and thickens as it attaches into the calcaneus and forms a thick fibrous band.
Every time you step, as the weight of the foot comes down, the plantar fascias acts like a bowstring. It tightens up to keep the arch of your foot intact.
When you look at the structure of the thick plantar fascia fibrous band, it is part of a larger structural element, which involves the Achilles tendon. The Achilles tendon which is the biggest tendon in the body, comes down from the calf muscles and it then thins and joins up with the plantar fascia as one single fibrous, um, a structure to allow shock absorbing and stepping off. But, and the Achilles tendon is a tendon, but the plantar fascia is a ligamentous structure.
The plantar fascia has an incredible amount of force applied to it. The force is spread over the toes, but is concentrated where the plantar fascia joins into the heel bone. When people have looked carefully at that area, there are a lot of blood vessels endings and nerve endings acting as stretch receptors.
What can happen over time is one of two things. The first is that you may have an acute injury. The injury could be from landing too hard and tearing the fascia slightly, or from a blunt injury like a stone, bone bruise where you step onto something which then tears the plantar fascia.
So that’s one scenario. The other scenario is more common, which is that over time, as you use your plantar fascia, it gets small tears. This type of wear and tear often occurs because of faulty biomechanics.
There is a whole science now of the biomechanics of the foot. Your foot has to perform two functions. The first is it needs to be a shock absorber. So as you put step and put weight onto your foot, it needs to absorb the force and remain structurally sound. All the ligaments, muscles and tendons attaching the foot bones together need to act in concert to do this.
Then, as you step off, your foot has to become a firm lever to give your whole body forward momentum. Your foot has to transition from one function to the other every time you step.
The way it does these transitions is through the biomechanics of the foot. As your foot comes down and it’s a shock absorber, it needs to be in an alignment that allows it to be loose and absorb the shock of the impact. It does this through a mixture of flection and extension of the ankle.
To spread force efficiently, your ankle uses two specific types of rotation: pronation and supination. Pronation and supination occur at the subtalar joint – a very complicated joint that allows the whole foot to twist.
If the biomechanics of the foot are sub-optimal, then its shock-absorbing ability is not as good as it should be. Therefore, as the foot transitions from shock-absorbing to being a lever, it will tend to overpronate.
This means the movement the foot has to go through to change from a shock absorber to a lever is exaggerated. This causes a lot more tension in the plantar fascia, and over time will stress it and cause damage.
In this situation, you get small tears in the plantar fascia. The tears initially become inflamed because your body is trying to heal them. This condition of inflammation is called plantar fasciitis. As time goes on, if the plantar fascia isn’t allowed to heal, it degenerates. This is because overstressing the plantar fascia stops the healing process.
In this scenario, the areas in the plantar fascia that were damaged are replaced by scar tissue – a material that doesn’t give you the tensile strength you need.
A damaged plantar fascia will give you a sharp, deep localized pain, not directly over the heel, but just forward of it. This is where the plantar fascia’s at its thickest and its narrowest, the point where it joins into the heel bone.
The time when plantar fasciitis pain is at its worst is first thing in the morning when you stand up. This is because overnight as you’ve been resting, the foot relaxes. The plantar fascia is completely de-stressed. As you put your foot to the ground, that first step is described as agony by people with a significant amount of plantar fasciitis. What’s happening is you’re going from a plantar fascia that is completely at rest and to one that is being hugely stressed.
As you go along through the day, the pain will vary depending on how much you walk and put pressure on the plantar fascia.
There are a few things that should be done to successfully treat plantar fasciitis. Then there’s some treatments that could be done but maybe shouldn’t be done. These are controversial parts of treatment. However, the majority of plantar fasciitis pain will settle if you do the following things.
First thing in the morning, as you wake up, take a tie and put it around your toes and gently pull on it. You’re starting to stretch the plantar fascia before you put weight on it.
Next, ask someone to bring you something cold and firm. One thing that works really is a soft drink bottle that’s been filled with water and left in the freezer overnight. This gives you an ice-cold, firm, round structure.
Put your foot onto the ice filled bottle, and roll it backward and forwards, slowly increasing the pressure. You’re icing your foot and at the same time stretching your foot.
Once you’ve done that, you’ll find that the first few steps are no longer agony, they’re a lot easier.
Once you’ve had your shower, you can rub in an anti-inflammatory gel. Either Voltaren or ibuprofen gel works ine. You could also use one of the salicylic acid gels, which are aspirin-containing, which are the things that contain wintergreen.
It’s also a good idea to rub in an antiinflammatory at night, to further reduce inflammation in your foot.
Next, you need to then go and see a decent podiatrist who will look at the biomechanics of your foot and your leg. They’ll help you get the correct pair of shoes. You’re looking for shoes that will support your foot, and limit to some degree the amount of pronation when you walk.
Usually, once you’ve found the correct shoe, the podiatrist will give you a heat moldable inner sole to use. This way, you have your foot supported throughout the day.
It’s important to rest in order to give your plantar fascia time to heal. Especially in the beginning, limit the amount of walking that you do each day, because it’s likey your plantar fascia is inflamed.
As you start to feel better, you can gradually increase the distance you walk every day. If in doubt, do less – you’ll get a better long term result.
The next important thing to look at is how your plantar fascia interacts with the rest of the structures in your leg.
This is where you look for trigger points. You need to stretch out your Achilles tendon and work on any trigger points which often occur in the calf muscles, particularly gastrocnemius and soleus. Trigger points in these muscles can refer pain over your heel and can mimic the pain of plantar fasciitis.
Because the calf muscles, plantar fascia and Achilles tendon are all part of a kinetic chain, stretching those out will make a huge difference.
If your calf muscles are tight, then as you go to step and move your knee forward over as you foot, that movement will put excess stress on the plantar fascia.
The gastrocnemius and soleus are the main ones for creating this tension, and they need to be stretched out and any active trigger points treated.
If your foot is hypermobile, ie. if there’s too much pronation, then what may happen is you may set up trigger points in the little muscles of the foot – called the intrinsics of the foot. They’re nowhere near as significant a cause of heel pain as plantar fasciitis and the gastrocnemius and soleus muscles.
So, the treatments we’ve looked at up until now are the simple treatments. Now, we come to the more invasive treatments. The one that’s been used for many years is to inject the heel with cortisone, which can be very effective in the short term.
But there are some big caveats with the use of cortisone. The first is that putting a needle into the sole of the foot is amazingly sore.
The second is that the injection has to be done accurately and the needle has to go right to where the plantar fasciitis is. When this is the case, as long as the dose is small, you will get significant reduction of inflammation of the area, which will help with the pain.
If you have an injection like this, and are also doing the stretches we’ve described, and treating the calf muscle trigger points, and making sure the biomechanics of your foot are optimum, then there’s a very good chance of success.
The problem comes when the injection isn’t accurate and if the dose of cortisone is too high. Then what can happen is the fat pad of the heel atrophies. Atrophy means that the fat pad in your heel actually shrinks away, which is a side effect of cortisone. This is a big problem because you need to have a fat pad over the heel as part of the foot’s shock absorption.
In conclusion, if somebody puts a shot of cortisone into your heel, and they use a big dose and don’t locate it accurately, you may end up worse off because you’ve taken away the shock-absorbing capability of your heel.
The heel pad will eventually grow back but may take nine months to a year to do this. So this is not a good plan.
If a shot is done, it should be the smallest dose, and it needs to be very accurate. Only one injection is needed, and it should be just one part of the treatment. In addition, you should be doing all the other things mentioned above.
There are other injections that can be done for plantar fasciitis. To some degree they are are safer than cortisone injections. There’s an injection called platelet-rich plasma, or PRP. You take blood and spin it down till you just have the supernatant, and inject that.
You can also inject glucose, which is known as prolotherapy. Glucose will reduce the inflammation and help aid with healing as will the plasma injections.
Another treatment involves taking a little machine with a piston. The piston pushes out a rod and this is used to hit the heel area. This increases the plantar fascia damage in a subtle way.
Strangely, this improves healing. The treatment is called extracorporeal shockwave therapy – ECST. The whacking piston is not strong enough to tear any structures, but enough to stimulate healing. It’s a very uncomfortable treatment, but somewhat effective and can be used to treat damaged tendons and plantar fasciitis.
The last group of treatments for plantar fasciitis are surgical. These should only be looked at after the other treatments (especially stretching and rest) have been tried.
The main surgical treatment involves cutting back bone spurs. When you do an xray of the heel bone, you may see something that looks like a bone spur. At this point, the radiologist may say “there is a bone spur coming out of the calcaneus” (heel bone.)
What you’ll see on the xray is a little pointed spicule of bone. In the past, it was imagined that the bone spur actually was digging into the plantar fascia and causing your pain.
Nowadays, it’s mostly recognized that this viewpoint is completely wrong. What you’re actually seeing is something quite different.
Where the plantar fascia inserts into the heel bone is a point where massive stresses occur. It’s the point where damage most commonly occurs.
The plantar fascia is soft tissue structure, and bone is hard. At the connection between bone and plantar fascia, what can happen is that as your body starts to heal, it gets slightly confused and lays down some calcium in the scar tissue.
When you look at this calcium deposit on an x-ray, it shows up as white. This makes it look like a spicule of bone, or bone spur. In fact, it’s actually calcium that’s being laid down in the plantar fascia a side effect of the healing process. That’s all it is, and it’s not a problem, or a cause of pain.
If you see this kind of bone spurs in an xray, it simply means there has been damage, which your body is healed. But that’s not the problem.
The problem is that you have had tears in the plantar fascia. Normally you would have to do an ultrasound or an MRI to look at the structure of the plantar fascia to see whether the tears are still there, and whether the fibers are degenerating.
There can also be bone spurs that occur as osteophytes in other parts of your foot. If you have wear and tear in a joint that’s quite different from what people call a bone spur in your heel.
There are complicated joints in the foot. They get a lot of pressure and have to often go through a large range of movement as you transition through your gait cycle. If you get damage, wear and tear in one of those joints, you may get extra bits of bone growth.
This may in fact become a problem because you’ve got a number of joints together and you may need that osteophyte shaved back so that the foot can move normally. But if you’re talking about a bone spur in the heel like the one in the picture above, it’s likely this isn’t the cause of your pain, it’s just extra calcium laid down as your body heals. Trying to scrape that back surgically is not going to help you at all.
If you’re interested in starting to treat calf trigger points to relieve pressure on your plantar fascia, here’s where to get started.