Placing an arch support (supportive type orthotic) underneath the feet is frequently prescribed to reduce foot pain. The arch supports prevent these muscles and ligaments from being stretched and thus reduce the pain. However, arch supports weaken the muscles and ligaments in the feet by supporting the arch. This is analogous to a leg cast weakening the muscles while supporting the leg.
As the muscles and ligaments in the feet become weaker, the unsupported arches (when the arch supports are not being worn) become flatter (See Photos below). As the arches become flatter, the foot pain increases. You become addicted to wearing the arch supports to control that pain.
Below photos are taken from the same patient: Pre vs Post use of a supportive type orthotic. Note the increase valgus heel rotation (pronation) as a result of using an arch support.
This becomes a vicious cycle:
- Arch supports are used to control foot pain, however at the same time, they make the muscles and ligaments in the feet weaker and weaker.
- As the muscles and ligaments become weaker and weaker, the arch drops more and more.
- As the arch drops more and more, you have more and more pain.
- As you have more pain, you use the arch supports more and more to control that pain.
Hence the vicious cycle. This is why, if you have a flexible flatfoot (e.g., Rothbarts Foot or a PreClinical Clubfoot Deformity), in most cases arch supports should be avoided.