“Plantar heel pain (PHP)” or “plantar fasciitis” is one of the major foot problems which can occur in any age group. It is a common encountered musculoskeletal problem that can cause disability, activity limitation, discomfort, and affect quality of life. It involves pain and inflammation of the plantar fascia, which runs across bottom of the foot and connects heel bone to toes. PHP frequently found in active workers aged between 25 and 65 years with the highest incidence in people aged between 40 and 60 years.
However, very few studies investigated the alterations of the multisegmental foot motions and muscle functions in patients with PHP. To prescribe the relevant program of treatment and reduce risk of symptoms chronicity, it is necessary to have in-depth understanding of changing mechanisms in patients with PHP. To explain how the symptoms occur in patients with PHP, foot function is another aspect that should be determined. One of the popular questionnaires determining foot function is the Foot Function Index (FFI) questionnaire. It has been proved to have a good reliability and validity and has been translated into several languages. To be able to use the international standard questionnaire, it is necessary to translate the FFI into Thai. This can be implemented in Thailand and be able to compare the findings of interventional effect internationally. In addition, very few studies reported the effectiveness of the treatment program for patients with PHP. Among previous evidences, the controversial findings existed. Thus, the intervention program should be evaluated for obtaining the effective treatment for this population.