Immediate and 12-week Effects of Exercise Versus Exercise and Instrument-Assisted Soft Tissue Mobilization for Plantar Fasciopathy Treatment: A Randomized Controlled Trial

Plantar fasciopathy (PF) is the most common cause of inferior heel pain, and approximately 40% of patients report symptoms two years following initial diagnosis. Exercise therapy, including gastrocnemius and plantar fascia stretching, and high-load strengthening have been shown to improve plantar fascia pain and function; however, not everyone improves with these interventions, and they require several weeks or months to be effective. The addition of instrument-assisted soft tissue mobilization (IASTM) techniques may improve these outcomes. Moreover, shear wave elastography (SWE) is an imaging technology that may provide helpful information regarding PF diagnosis and prognosis. Therefore, research is required to investigate changes in plantar fascia stiffness following exercise and IASTM interventions.

This study is divided into two Parts. Part I is a parallel-group, pre-test post-test randomized controlled superiority trial comparing the long-term effects of stretching and strengthening exercises (SS) (Group 1, n=35) versus SS plus IASTM (SS+IASTM, Group 2, n=35) in subjects with PF. The study is approved by the local Intuitional Review Board. The Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines for reporting of randomized interventional trials will be followed. Exercise interventions will be reported according to the Consensus on Exercise Reporting Template (CERT) guideline. Part II is a pre-test, post-test comparison of the short-term effects of IASTM on PF. Subjects from Group 2 of Part I (n=35) and a age and sex-matched healthy comparison group (Group 3, n=35) will participate in Part II.

Random group allocation into SS and SS+IASTM Groups will be performed by an independent statistician using the R Statistics package using a 1:1 allocation ratio with permuted block sizes of 2 to 6. Although it is not possible to blind study participants, the investigators performing the weekly interventions and measurements will be blinded to the subjects' group allocation.

After randomization subjects will receive a booklet that describes their condition and contains exercise instructions and an exercise training and medication usage diary. Group 1 will receive a sheet listing evidence for the beneficial effects of stretching and high-load strengthening. Group 2 will additionally receive information regarding the hypothesized benefits of IASTM. After group allocation and reading the appropriate booklet, subjects will complete the Credibility/Expectancy Questionnaire (CEQ), which contains six items requiring subjects to rate the credibility of the intervention and their expectations.

Both groups will perform an identical exercise program but will additionally receive once weekly IASTM treatments over an 8-week period. The weekly and total treatment time in Groups 1 and 2 will be the same, 15 minutes/week for 8 weeks. Group 3 (Comparison Group) will be recruited in clusters of five after every 5 subjects are recruited into Group 2 (SS+IASTM) and will be matched to that group's age and BMI.