Date of Award
Master of Science (MS)
School of Kinesiology and Recreation
Context: Much Research has been done to study what muscles best support the medial longitudinal arch (MLA). However these studies look at intrinsic or extrinsic muscles individually rather than comparing their effects at support of the MLA in a static stance. Researchers have yet to examine the changes to the MLA in the gait cycle rather than just looking at it from a static point of view. Objective: To study the effectiveness of two strengthening protocols for supporting the medial longitudinal arch during stance and gait. Design: Single-blinded, randomized control trial. Setting: Testing was completed in two athletic training facilities. Patients or Other Participants: A total of 24 recreationally active patients (14 females, 10 males) participated. Interventions: Individual strengthening protocols for intrinsic and extrinsic muscles respectively.Main Outcome Measure(s): Static measurements of navicular drop.Dynamic measurement of plantar pressure measuring contact area in square centimeters of the midfoot. To compare the effects of the intervention, two, one-way ANOVAs were used to compare change scores for the 3 intervention groups. Results: A significant difference between groups was found for the change in navicular drop (p=0.001), but not plantar pressure area (p=0.37). Post hoc comparisons for the change in navicular drop revealed a significant difference between the extrinsic and control group (p=0.001, effect size=2.15, 95% CI=0.92 to 3.38) and the extrinsic and intrinsic group (p=0.03, effect size=1.31,
95% CI=0.23 to 2.39), but no difference between the control and intrinsic group (p=0.31). Conclusions: These results appear to demonstrate that extrinsic muscles of the foot have a greater effect in support of the medial longitudinal arch during static stance. However, when dynamic measurements of plantar pressures were measured, there were no significant results noted for either intervention group. These results suggest that static standing exercises have no effect on dynamic support on the medial longitudinal arch of the foot. This can lead to future research to study what specifically causes dynamic changes of foot posture to occur.
KEYWORDS: intrinsic foot muscles; extrinsic foot muscles; medial longitudinal arch; pes planus
Schaefer, James D., "Supporting the Medial Longitudinal Arch: a Comparison between Intrinsic and Extrinsic Musculature" (2018). Theses and Dissertations. 884.