Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study

Zehra Duman Şahin; Selkin Yılmaz Muluk; Vedat Altuntaş; Evin Aslan; Şevval Dirican; Sevcan Uğur

doi:10.46332/aemj.1909378

Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study

Abstract

Purpose: This study aimed to investigate whether an early pain flare following extracorporeal shock wave therapy (ESWT) serves as a marker for favorable short-term clinical outcomes in patients with plantar fasciitis (PF) and to examine the association between calcaneal spur characteristics and flare occurrence.

Materials and Methods: This retrospective observational cohort study included 69 adults (aged 18–65) diagnosed with PF at a tertiary center between April and October 2025. All patients completed a standardized ESWT protocol consisting of three weekly sessions (12 Hz, 3.0 bar, 2000 shocks/session) without local anesthesia. Patients were categorized as flare-positive if they experienced a transient increase in heel pain within 72 hours post-treatment. Pain and function were assessed using the Visual Analog Scale (VAS) and Foot Function Index (FFI) at baseline and end of treatment. Statistical analyses included paired t-tests, Wilcoxon signed-rank tests, independent samples t-tests, and ANCOVA models to adjust for baseline imbalances.

Results: An early flare occurred in 26 patients (37.7%), typically within hours of treatment. Both groups showed significant improvements in VAS and FFI scores (p<0.05). However, there were no significant differences between groups in absolute change scores for pain or function. After adjusting for baseline scores, flare status was not independently associated with pain reduction (p=0.701) or functional recovery (p=0.435). Calcaneal spur presence and length were not associated with flare occurrence.

Conclusion: Early pain flare is a common, self-limited reaction following ESWT but does not predict superior short-term clinical response in plantar fasciitis.

Keywords

Supporting Institution

Funding The authors received no financial support for the research, authorship, and/or publication of this article. Conflicts of Interest Statement The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethical Statement

Ethical approval was obtained from the Ministry of Health Antalya City Hospital Clinical Research Ethics Committee (27.11.2025, no:17/144). The requirement for informed consent was waived due to the retrospective nature of the study.

Thanks

The authors thank Kader Koç (clinical secretary) for assistance with retrieval and organization of archived medical records. The authors declare that no financial support was received for this study.

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Details

Primary Language

English

Subjects

Pain, Rheumatology and Arthritis, Sports Medicine

Journal Section

Research Article

Authors

Zehra Duman Şahin ^*
0009-0005-5649-7583
Türkiye

Selkin Yılmaz Muluk
0009-0004-8147-938X
Türkiye

Vedat Altuntaş
0009-0009-2637-7416
Türkiye

Evin Aslan
0000-0001-6223-760X
Türkiye

Şevval Dirican
0000-0001-6490-6408
Türkiye

Sevcan Uğur
0000-0001-5617-629X
Türkiye

Publication Date

August 31, 2026

Submission Date

March 13, 2026

Acceptance Date

July 3, 2026

Published in Issue

Year 2026 Volume: 10 Number: 2

DOI

https://doi.org/10.46332/aemj.1909378

IZ

https://izlik.org/JA72TZ32JG

Cite

RIS / Bibtex

APA

Duman Şahin, Z., Yılmaz Muluk, S., Altuntaş, V., Aslan, E., Dirican, Ş., & Uğur, S. (2026). Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study. Ahi Evran Medical Journal, 10(2), 302-311. https://doi.org/10.46332/aemj.1909378

AMA

1.Duman Şahin Z, Yılmaz Muluk S, Altuntaş V, Aslan E, Dirican Ş, Uğur S. Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study. Ahi Evran Med J. 2026;10(2):302-311. doi:10.46332/aemj.1909378

Chicago

Duman Şahin, Zehra, Selkin Yılmaz Muluk, Vedat Altuntaş, Evin Aslan, Şevval Dirican, and Sevcan Uğur. 2026. “Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study”. Ahi Evran Medical Journal 10 (2): 302-11. https://doi.org/10.46332/aemj.1909378.

EndNote

Duman Şahin Z, Yılmaz Muluk S, Altuntaş V, Aslan E, Dirican Ş, Uğur S (August 1, 2026) Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study. Ahi Evran Medical Journal 10 2 302–311.

IEEE

[1]Z. Duman Şahin, S. Yılmaz Muluk, V. Altuntaş, E. Aslan, Ş. Dirican, and S. Uğur, “Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study”, Ahi Evran Med J, vol. 10, no. 2, pp. 302–311, Aug. 2026, doi: 10.46332/aemj.1909378.

ISNAD

Duman Şahin, Zehra - Yılmaz Muluk, Selkin - Altuntaş, Vedat - Aslan, Evin - Dirican, Şevval - Uğur, Sevcan. “Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study”. Ahi Evran Medical Journal 10/2 (August 1, 2026): 302-311. https://doi.org/10.46332/aemj.1909378.

JAMA

1.Duman Şahin Z, Yılmaz Muluk S, Altuntaş V, Aslan E, Dirican Ş, Uğur S. Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study. Ahi Evran Med J. 2026;10:302–311.

MLA

Duman Şahin, Zehra, et al. “Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study”. Ahi Evran Medical Journal, vol. 10, no. 2, Aug. 2026, pp. 302-11, doi:10.46332/aemj.1909378.

Vancouver

1.Zehra Duman Şahin, Selkin Yılmaz Muluk, Vedat Altuntaş, Evin Aslan, Şevval Dirican, Sevcan Uğur. Is Early Flare After Extracorporeal Shock Wave Therapy a Marker of Favorable Clinical Response in Plantar Fasciitis: A Retrospective Cohort Study. Ahi Evran Med J. 2026 Aug. 1;10(2):302-11. doi:10.46332/aemj.1909378