The short-term effect of custom-made foot orthoses in subjects with excessive foot pronation and lower back pain: A randomized, double-blinded, clinical trial

Study design: randomized, double-blinded, clinical trial. Background: Low back pain is one of the commonest disorders affecting the back. The literature reflects how over time excessive pronation of the foot has become to be recognized as linked to chronic low back pain, and how the problem can evolve for the better with the use of compensating foot orthoses. Objectives: The main objective of this study is to answer the question of whether the use of a certain type of custom-made foot orthosis alleviates low back pain. Material and methods: In a sample of 51 participants with excessive subtalar pronation and chronic low back pain (43 women and 8 men), the effect of custom-made foot orthoses in low back pain was studied. The study design was a randomized, double-blinded, clinical trial with two groups: experimental, treated with the custom-made foot orthoses, and control, treated with a placebo. Low back pain was evaluated by a visual analog scale for pain and Oswestry's Disability Index Questionnaire for lower back pain at two momentson the day of inclusion in the study and after 4 weeks of treatment. Results: The evolution of the low back pain showed significant differences in the experimental group, showing a significant reduction of pain and disability (p < 0.001, visual analog scale; p < 0.001, Oswestry's Index). Conclusions: In the sample studied, the use of custom-made foot orthoses to control foot pronation had a short-term effect in reduction of perceived low back pain. Clinical relevance If subtalar joint hyperpronation plays a fundamental role in the pathomechanics of lower limb, and this can facilitate the development of low back pain, then controlling the abnormal mobility of subtalar joint by means of foot orthoses should improve this symptom. This article could help solve this controversy.