Background: The literature shows an anecdotal relationship between high-arched feet and proximal fifth metatarsal stress fractures. This relationship has never been supported by sound scientific evidence. Our aim in this study was to examine whether athletes sustaining this injury are characterized by a static foot structure or a dynamic loading pattern during stance.

Materials and Methods: Ten professional soccer players who regained full professional activity following a unilateral proximal fifth metatarsal stress fracture and ten control uninjured soccer players were examined. Independent variables included static evaluation of foot and arch structure, followed by dynamic plantar foot pressure evaluation during stance. Each variable was compared between injured and uninjured feet.

Results: Static measurements of foot and arch structure did not reveal differences among the groups. However, plantar pressure evaluation during stance revealed relative unloading of the fourth metatarsal in both the injured and sound limbs of injured athletes compared with control, while the fifth metatarsal revealed pressure reduction only in the injured limbs of injured athletes.

Conclusion: Athletes who sustain proximal fifth metatarsal stress fracture are not characterized by an exceptional static foot structure. Dynamically lateral metatarsal unloading during the stance phase may either play a role in the pathogenesis of the injury, or alternatively represent an adaptive process.

Clinical Relevance: Footwear fabrication for previously injured athletes should not categorically address cushioning properties designed for high-arch feet, but rather focus on individual dynamic evaluation of forefoot loading, with less attention applied to static foot and arch characteristics.