Effectiveness of combining a proximal strengthening exercise program and foot orthosis on pain and performance among women with patellofemoral pain syndrome and a pronated foot: study protocol for a randomized clinical trial.

Backgrounds: Patellofemoral pain syndrome (PFPS) is one of the most frequent musculoskeletal disorders. Flatfoot and weakness of the hip and core muscles have been introduced as distal and proximal factors associated with this syndrome, respectively. The aim of this study is to investigate the effectiveness of a combination of a proximal strengthening exercise (PSE) program and a foot orthosis (PSEFO) on pain and function in women with PFPS and a pronated foot (PF).

Methods: In this randomized clinical trial (RCT), 117 female patients aged 18-40 years will be recruited through online announcements on cyberspace as well as those installed in rehabilitation and healthcare centers and gyms. Considering the inclusion criteria, the participants will be randomized into three groups of 39 (group I: practicing PSEs and wearing PSEFO; group II: practicing only PSEs; and group III: control group [CG]). Randomization will be conducted using the sequentially numbered, opaque, sealed envelope (SNOSE) technique. The intervention groups (groups I and II) will perform PSEs at gyms for 2 months at the rate of three sessions per week (each session lasting 45-60 min) under the guidance of a trainer. In addition to the PSE, group I participants will receive prefabricated polyurethane FOs with an 8° varus wedge. They will be asked to wear the orthosis for 2 h a day and then slowly increase their wearing time to a full day. The CG participants will follow their routine lives during this study. Pain, as the primary outcome, will be measured by the visual analog scale before and after the 8-week intervention program. Additionally, quality of life, disability, Q angle, performance, and dynamic balance will be evaluated as secondary outcomes using the 36-item Short Form Health Survey, the Kujala score, a goniometer, the step-down test, the unilateral squat test, the anteromedial lunge test, the bilateral squat test, and the Y-balance test, respectively.

Discussion: In this RCT, the effectiveness of PSEs focusing on the hip and core muscles, with and without FOs, on pain and performance among women with PFPS and PF will be investigated and compared.

Trial Registration: The present study was approved by the Research Ethics Committee of Guilan University of Medical Sciences, Rasht, Iran (code: IR.GUILAN.REC.1402.021) and registered on the Iranian Registry of Clinical Trials (IRCT, code: IRCT20230604058380N1) at 28 July 2023.