Does Orthotics work to reduce pain?
Plantar orthotics have been proven to be effective in reducing pain for several conditions in the knee, ankle, and foot. Most of the time they are used to reduce the pain associated with pathology in the short term (3 to 6 months).
Despite their effectiveness in reducing pain and thereby increasing the quality of life of people, both health professionals and the general population have difficulty understanding their mechanism of action.
The effectiveness of foot orthotics has long been explained by their potential ability to realign the foot, leg, or thigh. However, the most recent studies tell us that their beneficial effect would not be explained by the latter. Indeed, the orthosis would have very little effect on the alignment of the foot, leg, or thigh.
Two main theories have emerged as to their potential effectiveness. The neuroproprioceptive effect as well as the effect on the forces acting on the foot. The neuroproprioceptive effect is explained by the fact that the feet have many nerve endings. They are very sensitive to the sensory changes that plantar orthotics can bring.
This effect can have repercussions on the efforts that the muscles will have to produce. However, there are few studies regarding their effect on nerve endings, and much remains to be discovered on this topic. Currently, therefore, there are no clinical recommendations that can guide clinicians.
How it works?
Currently, the best theory explaining their beneficial effect would be by changing the forces that are applied to the foot. They would therefore reduce the stress on certain injured structures. For example, people with metatarsalgia would see the plantar pressure exerted by the soil on the metatarsals reduced by foot orthotics.
This theory fits very well into a mechanical stress quantification (QSM) approach. The plantar orthosis would therefore be a tool to better quantify its mechanical stress. Indeed, there are currently several studies on the effect of orthotics in terms of their influence on the forces acting at the level of the foot that help guide clinicians.
It is important to analyze and choose the patients who may benefit from this treatment, as many other treatments may be more appropriate than plantar orthosis.