Three-dimensional foot-ankle exercise versus clam exercise in addition to short-foot exercise in individuals with flexible flatfoot: a randomized controlled trial

Abstract

Background: Three-Dimensional (3D) foot-ankle exercise and clam exercise have been used to improve foot posture in flatfoot. However, studies on this topic are limited, and more supporting evidence is needed to investigate the benefits of these exercises on flatfoot. Purpose: To compare the effects of 3D foot-ankle and clam exercise in addition to Short-Foot exercise on navicular drop, foot posture and structure in individuals with flexible flatfoot.

Methods: Single-blind, randomized controlled trial. Fifty-six participants were divided into Foot Exercise Group (FEG), Hip Exercise Group (HEG), and a Control Group (CG). FEG performed 3D foot-ankle+Short-Foot exercise. HEG performed clam+Short-Foot exercise. CG performed only Short-Foot exercise. The Navicular Drop Test (NDT), Foot Posture Index-6 (FPI-6), Clarke's Angle (CA), Staheli Index (SI), Wejsflog Index, hallux valgus angle, and varus deformity angle of the fifth toe were assessed pre-and post-intervention (six week later).

Results: Post-intervention, NDT, CA, and SI scores improved significantly more in FEG compared to other groups (p = <0.001, η2 = 0.425-0.802). FPI-6 score decreased similarly in FEG and HEG (p = .477), significantly more than in CG (p = <0.001, r = -0.692; p = <0.001, r= -0.560, respectively). CA and SI scores improved more in HEG than in CG (p = <0.001, r = -0.851; p = <0.001, r= -0.536, respectively). Conclusion: The 3D foot-ankle and clam exercise may be an effective intervention that provides satisfactory functional results for navicular drop, foot pronation, and anthropometric properties of the foot in flexible flatfoot. Clinical trial registration number: NCT06313125.