Investigation of foot function, pain, flexibility and muscular performance levels according to the degree of pes planus in patients with plantar fasciitis: a cross-sectional study
Tuğba Kocahan1
, Ayfer Ezgi Yilmaz2, Hüseyin Günaydin3, Bihter Akinoğlu4
1Department of Sports Medicine, Gülhane Faculty of Medicine, Health Sciences University, Ankara, Türkiye
2Department of Statistics, Hacettepe University, Ankara, Türkiye
3Department of Sports Medicine, Gülhane Training and Research Hospital, Health Sciences University, Ankara, Türkiye
4Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Ankara Yıldırım Beyazıt University, Ankara, Türkiye
Keywords: Plantar fasciitis, pes planus, foot function, pain, flexibility
Abstract
Objective: The aim of this study was to investigate how the degree of pes planus (PP) affects pain, flexibility, muscle performance, and foot functionality in individuals with plantar fasciitis (PF).
Material and Methods: The study included 58 individuals with PF. Participants were divided into three groups based on their PP degrees determined by the Feiss line test: '0' (no PP), '1' (Grade 1 PP) and '2' (Grade 2 PP). Pain intensity was assessed using the Visual Analog Scale (VAS), flexibility was evaluated using gastro-soleus and plantar fascia flexibility tests, muscle performance was measured using the Heel Rise test, and foot functionality was assessed through the Foot Function Index (FFI).
Results: No differences were found among the groups in terms of pain intensity, gastro-soleus flexibility, muscle performance, and foot functionality (p>0.05). A significant difference was observed in plantar fascia flexibility between groups '0' and '1', with greater flexibility in the group without PP compared to those with Grade 1 PP (p=0.024); groups '0'-'2' and '1'-'2' revealed similar results (p=0.431; p=0.494).
Conclusion: The degree of PP appears to have a limited impact on pain, gastro-soleus flexibility, muscle performance, and foot functionality in individuals with PF, although it may affect plantar fascia flexibility. Current evidence is insufficient to support treatment modifications based solely on PP degree. Future studies with larger samples and objective biomechanical assessments are needed to further clarify these relationships.
Cite as: Kocahan T, Yilmaz AE, Günaydin H, Akinoglu B. Investigation of foot function, pain, flexibility and muscular performance levels according to the degree of pes planus in patients with plantar fasciitis: a cross-sectional study. Turk J Sports Med. 2026;61(2):96-103; https://doi.org/10.47447/tjsm.0935
The approval for this study was obtained from Ankara Yıldırım Beyazıt University University Clinical Research Ethics Committee, Ankara, Türkiye (Decision no: 01-531, Date: 16/01/2024).
Consept: TK, BA; design: TK, BA; supervison: TK; materials: TK,HG; data collection and/or processing: TK,HG; analysis and interpreta‐tion: AEY; literature review: TK,HG; writing manuscript: TK; critical reviews: BA. All authors contributed to the final version of themanuscript and discussed the results and contributed to the final manuscript.
The authors declared no conflicts of interest with respect to authorship and/or publication of the article.
The authors received no financial support for the research and/or publication of this article.
