By Karina Teahan
Metatarsalgia is a common overuse injury in runners. It is a general name describing pain under the heads of your metatarsal bones. This is an area on the sole of your foot, often referred to as the “ball” of your foot.
So metatarsalgia is a symptom, rather than a specific diagnosis. It may be caused by a number of different conditions affecting your foot. Treatment will depend on the underlying cause.
Anatomy
Our feet are amazing. They take the weight of our whole body, and this load is further increased when we run.
Our foot is divided into the rear foot, the midfoot (a pyramid-like collection of bones that help form our arch) and the forefoot which is made up of 5 long bones (metatarsals) and our toes (phalanges). In total there are 26 bones in our foot.
Along with these, are many muscles, ligaments, tendons, bursae, blood vessels and nerves so our feet really are complex structures.
Symptoms of Metatarsalgia
It usually begins over time. It may feel like you are walking with a pebble in your shoe, and can be under one or more of your metatarsal heads (bony joints on the ball of your foot). The pain can be diffuse or sharp and shooting.
If nerves are involved there may be numbness, burning and tingling in some of your toes. It may feel better when you rest your foot, or when non-weight bearing, but will worsen as you stand, walk, run and in particular if you are barefoot.
Running is a high-impact, repetitive sport, and during each run cycle we push off our forefoot, so it is not surprising that this area can be prone to injury. The impact of forces on the foot during running approach 3-4 times body weight.
The average runner will strike the ground 480-1200 times per kilometre! We become more susceptible to metatarsalgia if one or more of the following apply to us and they include both internal and external factors:
- Overuse: a sudden increased your training load (volume or intensity)
- A stiff ankle will result in extra time on our forefoot during the run cycle
- Reduced calf length will result in excessive pronation and increased load through our first metatarsophalangeal joint.
- Wearing high heeled shoes puts added pressure on our forefeet; wearing poorly fitted tight shoes may also contribute.
- Having prominent metatarsal heads (that have dropped down a little)
- Tight toe extensor muscles
- Weak toe flexor muscles
- Having a hypermobile (extra flexible) 1st toe
- Pes Cavus: a very high arch
- Excessive pronation: being very flat footed
- Callus formation, which is a sign of abnormal stress on a focal area but it can be very painful and can lead to a corn
- A short first metatarsal or a long second metatarsal, seen in people with a Morton toe (the 2nd toe appears longer that the 1st) will alter your foot mechanics and mean increased weight is taken through your second metatarsal
- Morton’s neuroma (interdigital neuroma) in which one of the nerves that run between the metatarsal bones in the foot becomes irritated and inflamed. It is most common between the 3rd & 4th toes. In some people you can feel this tender mass/neuroma, and a” clicking” between the bones of your feet.
- Stress fracture in one of the metatarsals
- Plantar plate disruption (this will be diagnosed by your Physiotherapist or Podiatrist)
- Degeneration of the cushioning fat pads under the metatarsal heads. This occurs with increasing age
- Carrying extra weight. A healthy weight range is having a BMI between 20-25
- Other orthopaedic foot abnormalities: bunion, claw toe, hammer toe
- Certain diseases: inflammatory arthritis such as Rheumatoid Arthritis, Gout, Reiter’s Disease, Psoriatic Arthritis, tumour, Avascular necrosis (AVN) can give rise to foot pain. These would need to be managed by your doctor or a rheumatologist.
How is Metatarsalgia diagnosed?
Your physiotherapist will examine your foot, ankle and footwear. This examination and your subjective history of how the pain came on will lead to a diagnosis in the majority of cases, and treatment will start from here.
Pressure sensor mapping systems can be useful in the assessment of abnormal loading patterns that may be leading to your forefoot pain, but only if coupled with a physical examination, history and interpretation by an expert clinician.
In occasional instances where the diseases mentioned above, or a stress fracture, are suspected, you will be referred back to your GP for further imaging (x-ray, MRI, ultrasound) or bloods.
In the case of a significant biomechanical abnormality, like a severe bunion that does not respond to conservative management, you may be referred to an orthopaedic surgeon for corrective surgery.
However, the majority of instances can be very well managed under the guidance of your physiotherapist and there is a lot you can do for yourself.
Treatment
- The initial goal is to off-load the painful area and allow it to heal. This involves stopping running until the pain and inflammation settle.
- This can be further assisted by icing the affected area (oil the skin first) for 3 minutes x 4 times/day covering the area in circular movements with your ice cube for 3-4 days.
- Over the counter medications can be discussed with your pharmacist to help with pain and inflammation.
- Avoid being barefoot even in the house – get house trainers until the pain settles.
- Unload the affected area with padding. Depending on the joint(s) affected this may take the form of a met-bar or a met dome which are placed behind the metatarsal heads to help redistribute the load across your foot more evenly. This may only be needed temporarily.
I find the devices shown in the photos below can really ease the pain of metatarsalgia. Depending on where your pain is will decide which you use.
You can fit it yourself by drawing your foot on a piece of paper or your run shoe liner. Put a colour on your metatarsal heads 1-5 (bony joints on the ball of your foot, I used lipstick!). Stand on the paper and then you know where your met heads are.
The foam goes behind your met heads and not under them. You can stick the foam to your shoe liner with double sided tape. For me the last one stays in place in my running socks as they are quite tight but is a little bit tedious putting it in every time.
- If your foot is more complex (high rigid arch or excessive pronation) you may need to consider a custom (or at times off the shelf) orthotic as prescribed by your physiotherapist or podiatrist. You may just need these for your running shoes. Remember your foot functions differently when you run and walk.
- Stretch and strengthen your toe muscles if they are tight or weak, compare them to your other non-affected foot.
- Consider areas further up the chain, as weakness in our hip and gluteal muscles can cause a functional over-pronation further down.
- Treat any callus. This can be done simply at home by bathing your feet and paring down the hard skin with a pumice file. Do not be too aggressive or cause the skin to bleed. Instead of a radical paring, you should aim to do it more often. Moisturise your feet and change your socks 1-2 times a day. If you find it difficult to get rid of your callus yourself or feel a corn is developing then you should really go to see a chiropodist.
- Calf stretches and ankle mobilisations will rectify stiff ankles.
- Toe mobilisations such as longitudinal traction or dorsal/plantar glides (depending on direction of stiffness) as directed by your physiotherapist can be really useful to regain normal mobility of your first MTP joint if it has gotten stiff.
- Make sure you wear a running shoe suitable for your foot type. We have so much choice. Get the expert opinion of a good running shoe store. Remember to change your shoes when you feel the cushioning support has gone. This will vary for different athletes depending on their weight/build, mileage, and running gait efficiency (some land heavier than others). Make sure your toes have adequate space and aren’t being squeezed in the toe box part of the shoe.
- Keep high heels for special occasions and put gel pads in them to give a little extra cushioning. Wedge type shoes are kinder to your feet than stilettos!
- Avoid flip flops as they cause our toes to claw and increase the load through our metatarsal heads
- Cross train while you can’t run to keep up your fitness.
- Patients diagnosed with Morton’s Neuroma may respond to a more rigid orthotic with a metatarsal dome (as in photo above) but if conservative management doesn’t work may need to be referred on for a nerve block in combination with long acting steroids. The causes of the Morton’s Neuroma which are among the causes for metatarsalgia already mentioned still need to be addressed.
Prevention & Return to Running
Preventing re-injury means addressing the risk factors that caused your metatarsalgia in the first place as have been discussed above. You can return to running when you are completely healed and free of symptoms.
Make a gradual return, as a sudden return to pre-injury levels of training would risk a recurrence of this injury or a new one. Maintain a good diet for bone health. In general the prognosis is very good, especially once you address it early. By addressing the risk factors and following the advice outlined here you will hopefully be back happily running before you know it.
Best of luck!
All images Karina Teahan.
